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Best Inorganic Chemistry Frontiers Covers of 2021

We are delighted to announce the Best Inorganic Chemistry Frontiers Covers of 2021!

Read below the scientific papers.

A red-light-chargeable near infrared MgGeO3:Mn2+,Yb3+ persistent phosphor for bioimaging and optical information storage applications

Inorg. Chem. Front., 2021,8, 5149-5157
https://doi.org/10.1039/D1QI01158H

Issue 24 Volume 8 Outside Front Cover

Binuclear metal complexes with a novel hexadentate imidazole derivative for the cleavage of phosphate diesters and biomolecules: distinguishable mechanisms

Inorg. Chem. Front., 2021,8, 2684-2696
https://doi.org/10.1039/D1QI00108F

Issue 11 Volume 8 Inside Front Cover

Designing lanthanide coordination nanoframeworks as X-ray responsive radiosensitizers for efficient cancer therapy

Inorg. Chem. Front., 2021,8, 3433-3439
https://doi.org/10.1039/D1QI00442E

Issue 14 Volume 8 Inside Front Cover

Congratulations to the winners of Best Inorganic Chemistry Frontiers Covers of 2021!

We expressed our sincere appreciation for all the support and contributions from our authors, reviewers, and readers in the past 2021.

Looking forward to receiving your high-quality work in 2022.

Happy Chinese New Year!

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A highly active and E-selective Co catalyst for transfer-semihydrogenation of alkynes

The efficient semihydrogenation of internal alkynes to selectively produce either E– or Z-alkenes is one of the main challenges in homogeneous catalysis. Numerous systems were reported in the past, however, such reactions typically require either the use of gaseous hydrogen at high pressure, noble metal catalysts, or rather high catalyst loading at long reaction times, the latter resulting in alkene isomerisation or overreduction to produce alkanes. Amine boranes such as ammonia borane (H3B·NH3) are known to be well-suited for transfer hydrogenation reactions, providing stoichiometric amounts of H2 either by dehydrogenation (i.e. H2 production), followed by hydrogenation, or by stepwise hydride and proton transfer to an organic substrate. Homogeneous precatalysts based on the Co(II) oxidation state have been reported in the past, however, mechanistic insights into such systems were rather limited to date.

Recently, the groups of Jiao and Beweries at LIKAT Rostock have demonstrated that PNN(H) Co(II) complexes serve as very efficient precatalysts for the selective formation of E-alkenes at very mild conditions, suing MeOH and H3B·NH3 as the hydrogen source. This reaction is suggested to take place exclusively via the Co(II) oxidation state, which was corroborated though a combination of control experiments, EPR spectroscopy, and DFT analysis. Key feature for the high activity of this Co system is the proton responsive PNN(H) ligand, possessing a pyrazole fragment that undergoes deprotonation during catalyst activation. The results presented herein could be relevant for the design of other proton responsive ligands for non-noble metal free transfer hydrogenation reactions.

Corresponding author:

PD Dr. Torsten Beweries (Leibniz Institute for Catalysis, Rostock)

Torsten Beweries is head of the department Coordination Chemistry and Catalysis at the Leibniz Institute for Catalysis in Rostock (Germany). He received his PhD in Chemistry at LIKAT in 2008, working on the coordination chemistry of hafnocenes. He then moved to the University of York (UK) for a postdoctoral stay with Prof. Robin N. Perutz in 2009, working on late transition metal complexes for halogen bonding. He returned to LIKAT in 2010, where he established an independent research group. The research field of PD Dr. Torsten Beweries is organometallic chemistry and homogeneous catalysis with focus on new pincer ligands and complexes, main group polymers, and unusual metalacyclic systems. He is the author of 91 articles indexed by SCI and cited more than 1600 times with an index H = 23.

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Unprecedented Organometallic Rare Earth Complexes Containing a Large, Flexible Salophen Ligand

Organometallic chemistry of the rare earth and actinide elements has been a driving force for the development of novel functional materials and catalysts for decades, giving rise to impressive advances in the fields of single-molecule magnetism, luminescence, and polymer sciences. Excitingly, organometallic approaches have always been on the forefront of fundamental chemistry and allowed breakthroughs in the field, not only with the lighter metals but also some of the heaviest actinide candidates. The inherent reactivity of organometallic compounds owing to the apparent labile and reactive metal-carbon bonds renders the isolation and characterization of such molecules exceptionally challenging, especially when aiming at polymetallic rare earth complexes, and is therefore underdeveloped to this date. Consequently, the exploration of suitable synthetic routes to access bridged organometallic metallocene complexes is of great interest for the rare earth and more general inorganic chemistry community.  

Recently, the group of Selvan Demir at Michigan State University has demonstrated that two rare earth metallocene fragments are able to capture the tetradentate salophen ligand, giving rise to the first series of dinuclear salophen-bridged rare earth metallocene complexes with the metals yttrium, gadolinium and dysprosium, Figure 1. These molecules also constitute the first metallocene salophen complexes for any metal ion. Remarkably, the flexibility of the salophen bridge allows the binding pockets to face outwards upon complexation to the metal ions which is a rare, yet intriguing, coordination mode. Consequently, a substantial separation of the metal centers (7.858 – 7.895 Å) occurs leading to weak electronic or magnetic communication between the rare earths. Since the magnitude of magnetic exchange coupling between paramagnetic metal centers and/or organic radical is crucial for the generation of better-performing multinuclear single-molecule magnets,  the magnetic communication in these salophen complexes was explored. 

Figure 1. (A) Schematic view of the salophen-bridged rare earth metallocene complexes. (B) Structure of the rare earth molecules as obtained through single-crystal X-ray diffraction. (C) Arial view of the calculated highest occupied molecular orbital.

The dynamic magnetic properties of the paramagnetic dysprosium complex revealed characteristics of single-molecule magnet behavior, while the static magnetic susceptibility data collected for the paramagnetic gadolinium complex allowed quantification of the magnetic exchange, Figure 2. The determined coupling is of similar magnitude to other polynuclear rare earth complexes containing diamagnetic bridging ligands. DFT calculations on the diamagnetic yttrium conger revealed negligible orbital overlap between the metal center and the salophen ligand in the highest occupied molecular orbital, Figure 1, which may account for the weak magnetic coupling in the paramagnetic variants.

Notably, the lowest unoccupied molecular orbital might be able to be populated with an unpaired electron. Radicals, innate to unpaired electrons, promote strong exchange coupling when placed between rare earth magnetic moments and are, thus, extremely sought-after in the fields of single-molecule magnetism and spintronics. Excitingly, cyclic voltammetry measurements of the salophen

Figure 2. (A) Electron uptake of the dysprosium molecule via electrochemistry. (B) Single-molecule magnet features of the dysprosium complex.

complexes revealed a quasi-reversible feature attributed to the reduction and oxidation of the salophen bridge on the timescale of the electrochemical experiment, Figure 2. This paves the way for chemical reductions of these molecules to generate coveted metal-radical compounds in the future. Noteworthy, chemical functionalization of the salophen backbone may readily be attained which serves as an additional path to augment magnetic coupling and as such highlights the enormous potential of the salophen ligand in organometallic chemistry.

Selvan Demir is an Assistant Professor of Chemistry at Michigan State University. She earned her Dr. rer. Nat. at the University of Cologne researching on scandium solid state chemistry with Prof. Gerd Meyer and scandium organometallic chemistry with Prof. William J. Evans at the University of California, Irvine. Subsequently, she focused on lanthanide-based single-molecule magnets and porous aromatic frameworks with Prof. Jeffrey R. Long at the University of California, Berkeley, and worked on transuranics with Dr. David K. Shuh at the Lawrence Berkeley National Laboratory. Afterwards, she took up a junior professorship of inorganic chemistry at the University of Göttingen. Since 2019, she researches with her group at Michigan State University, on various areas surrounding the chemistry of the rare earth elements and actinides. The research group focuses mainly on organometallic chemistry, small molecule activation, single-molecule magnetism, and lanthanide/actinide separations. A particular emphasis is also on heavy p-block element and uranium chemistry.

 

 

 

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Enantioselective chiral sorption of 1-phenylethanol by homochiral 1D coordination polymers

Amongst the myriad uses of metal-organic frameworks (MOFs) and coordination polymers, separation of complex mixtures, either gaseous or in solution, is one of the most promising applications due to the regular array of well-defined pores. Integration of specific points of interaction that are complementary to the targeted guest species can provide highly selective materials. In particular, precise control of the 3D space within pores may provide a mechanism for enantioselective discrimination for which the exact spatial arrangement of multiple sites of interaction is paramount.

The vast majority of research in this area is driven by 3D metal-organic frameworks, often those possessing permanent porosity. However, for solution-based applications this need not be a prerequisite and materials comprising lower dimensionality coordination polymers may be just as effective is they contain solvent-filled pores.

Recently the group of David Turner at Monash University has shown that a 1D coordination polymer, with pores formed by alignment of loops within the 1D chain, is capable of sorbing 1-phenylethanol with a good degree of enantioselectivity (Figure 1). A closely related material shows no such selectivity, and a reduced uptake capacity, highlighting the importance of structural match between the host framework and the analyte. Ground samples showed higher uptake than unground crystals for the active material, suggesting an influence of surface area or ease of permeation into the solid. Both static (soaking) and dynamic (“micro-LC”) methods showed enhanced uptake of one enantiomer from a racemic solution of 1-phenylethanol, albeit not perfect separation. The group was also able to crystallographically determine the binding site of the preferred enantiomer (Figure 2), showing an array of hydrogen bonding interactions that lie behind the enhanced uptake of one enantiomer over the other.

These results highlight the potential of non-3D coordination polymers in chemical separations and demonstrate the array of host-guest interactions that are required for separations of very similar compounds.

Figure 1. The chiral material contains guest-filled pores resulting from the alignment of loops within the 1D coordination polymer.

Figure 2. The preferred enantiomer of the guest is found crystallographically within the binding pocket, highlighting the array of interactions that hold it in place and provide the enantioselectivity.

Corresponding Author:

David Turner is a Senior Lecturer in the School of Chemistry at Monash University, Australia. After receiving his PhD in 2004 from King’s College, London, he held a number of fellowships at Monash University prior to joining as a Faculty member. Research in the Turner group revolves around metallosupramolecular assemblies, exploring both coordination polymers/MOFs and coordination cages with a particular emphasis on chirality. Dr Turner has published over 130 papers, in addition to two books, attracting almost 5000 citations and an h-index of 32.

https://research.monash.edu/en/persons/david-turner

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A New 2D Layered Aluminophosphate |Hada|6[Al6(PO4)8](H2O)11 Supported Highly Uniform Ag Nanoparticles for 4-Nitrophenol Reduction

Since Wilson and Flanigen found the first microporous aluminophosphate (AlPO) in 1982, the synthesis of AlPO materials with novel frameworks and study their potential properties, such as adsorption, catalysis, and separation, has attracted intense interest of researchers. As the main family of AlPO based materials, 2D layered materials show a rich variety of structures and compositions depending on the diverse coordination and connection modes of Al and P atoms. In recent years, 2D materials, possessing highly exposed surfaces and diverse structures, have become a dramatic category of supports. However, 2D molecular sieves are serving as catalyst supports are very few.

Recently, Prof. Jiuxing Jiang at Sun Yat-sen University and Dr. Jiang-Zhen Qiu of Zhongkai University of Agriculture and Engineering synthesized a new 2D layered aluminophosphate compound by adopting rigid and bulky template of 3,5,N,N-tetramethyladamantane-1-amine (ada) through hydrothermal conditions, which is named the Zhongkai University of Agriculture and Engineering NO.1 (ZHKU-1), with the composition |Hada|6[Al6(PO4)8](H2O)11. The structure of ZHKU-1 was constructed from the alternate connection of AlO4 and triply bridged PO4 tetrahedra ([O=PO3]3-) to form a 4, 6, 12-net (Figure 1). The inorganic sheets are linked and separated by protonated amine and H2O molecules by extensive H-bonds, giving a new 2D structure with an interlayer space of 19.6 Å.

Figure 1 Crystal structure figures of ZHKU-1

ZHKU-1, as a 2D material with a more exposed surface, could be adapted for encapsulating metal nanoparticles (NPs). Ag species are immobilized on the supports of ZHKU-1 by UV reduction and deposition, forming the catalyst of Ag@ZHKU-1 with high loading of 4.9 wt%. The HRTEM images reveal the highly uniform Ag clusters with visually observed sizes of 1.9 nm (Figure 2).

Figure 2 The characterizations of Ag@ZHKU-1 for HRTEM and corresponding mapping images

Since 4-nitrophenol (4-NP) is a notorious industrial pollutant, Ag@ZHKU-1 is applied to the model reaction for 4-NP reduction. The catalytic results show that the reduction reaction of 4-NP into 4-aminophenol could be completely performed within 75 s in NaBH4 solution (Figure 3). Moreover, the catalytic activity was almost the same, with almost 99% conversion after eight cycles. The remarkable catalytic activity and recyclability of Ag@ZHKU-1can be attributed to the high dispensability of Ag nanoclusters confined to the 2D support, which provides more accessible Ag active sites to 4-NP.

Figure 3 Catalytic activity and recycling tests for 4-nitrophenol reduction are over Ag@ZHKU-1 catalyst

This work reports a new 2D layered aluminophosphate compound, which expends the aluminophosphates family. Furthermore, the confinement of metal Ag on this new layer structure through photodeposition gives rise to a small size (~1.9 nm) of AgNPs with homogeneous dispersion. The catalyst of Ag@ZHKU-1 shows excellent catalytic activity and high conversion for 4-nitrophenol reduction. This work is significant for designing 2D aluminophosphate materials to confine small metal nanoparticles for catalytic application.

Prof: Jiuxing Jiang (ORCID: 0000-0001-9664-3235). I received Ph.D degree from Jilin University in 2010. Afterward, I spent 5 years for a Post Doc. stay in Instituto Technologia Quimica (UPV-CSIC) in Valencia Spain supervised by Prof: Avelino Corma. After independent work in Sun Yat-sen University (2015-now), I keep my interesting on the topologically new zeolite synthesis (four three letter code, IRR, -IRY, -IFU, -SYT were granted by Structure Committee of Internation Zeolite Association), and zeolite based heterogeneous catalysis, such as: acid-base catalysis, catalytic ammonium synthesis, NH3-SCR for deNOx reaction, porous materials for energy storage, etc. I have published more than 20 high-impact journal articles, such as Science, Angew. Chem. Int, Ed, Chem.Sci, Chem. Mater. etc. Among them, the work on the synthesis and structure of zeolite ITQ-43 was published in Science, 2011, 333, 1131-1134 and was selected as annually breakthrough of 2011 by Science. Currently serve as a member of Zeolite Committee of Chinese Chemical Society and youth editorial member of Journal of Chemical Research in Chinese University.

Jiang-Zhen Qiu: She received her Ph.D. degree in 2019 from Sun Yat-sen University with M.S. Supervisor Prof. Ming-Liang Tong and Ph.D. Supervisor Prof. Jiuxing Jiang. In 2020, she was introduced to Chemical Engineering of Zhongkai University of Agriculture and Engineering as an “Excellent Doctor”. Her interested research fields include synthesizing new topological structures of zeolite and exploring multifunctional materials with novel functionalities such as light, conductivity, magnetism, or catalysis. Currently, she and her collaborators published 10 papers in related fields, such as Chem. Mater., Chem. Sci., Inorg. Chem. Front., Chem. Commun., Chem. Eur. J.

 

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Optimizing the relaxivity at high fields: systematic variation of the rotational dynamics in polynuclear Gd-complexes based on the AAZTA ligand

Magnetic Resonance Imaging (MRI) is one of the most important and prominent techniques in in clinical diagnostic medicine, in preclinical studies and in biomedical research. As well as many other imaging modalities, MRI also makes extensive use of contrast agents (CAs) that allow achieving remarkable improvements in medical diagnosis in terms of higher specificity, better tissue characterization and functional information. For the vast majority, the clinically used CAs are coordination complexes in which a GdIII ion is encapsulated within octadentate chelators based on polyaminocarboxylate anions and has a directly bound water molecule. Their use is widespread and is estimated to correspond to approximately 40 million administrations per year of GdIII chelates worldwide.

Their effectiveness (relaxivity; the increase in the relaxation rate R1 of the water protons normalized to a 1 mM concentration of the paramagnetic ion) at the magnetic fields of clinical interest is dominated and limited by the fast rotational dynamics and tends to decrease with the increased magnetic field. However, the current trend in MRI development is towards higher magnetic field strengths and most scanners operate at 1.5 or 3 T, while there is increasing use of those at 7 T. Therefore, a different approach for the relaxivity enhancement of Gd-based CAs becomes necessary for the modern high-field systems.

Recently, the group of Mauro Botta and colleagues from the University of Eastern Piedmont in Alessandria (Italy) investigated the optimization of the efficacy of Gd-based CAs, between 1 and 7 T, by systematically modulating the rotational dynamics through the synthesis of polynuclear systems containing between two and eight GdIII chelates (Figure 1).

Figure 1. [Gd(AAZTA)(H2O)2] and polynuclear Gd2-6L2-L6 complexes 

The [Gd(AAZTA)(H2O)2] chelate was used as a building block due to its remarkable properties: a) ease and high-yield synthesis, presence of two inner sphere water molecules in fast exchange with the bulk; b) high thermodynamic stability; c) kinetic inertness in the presence of physiological concentrations of CuII and ZnII higher than that of the clinical agent [Gd(DTPA)]2-; d) negligible tendency to formation of ternary complexes with endogenous anions. The study demonstrates that the strategy for relaxation enhancement varies with the strength of the magnetic field used.

Up to 3 T, efficacy is limited by molecular rotation and therefore increases proportionally with the increase in molecular size. Between 3 and 7 T, the issue of local flexibility or anisotropic rotation, evaluated with NMR techniques and computational models, becomes more and more relevant and medium-sized rigid systems (tri- or tetranuclear) provide the best results. At ultra-high fields (> 7 T), small and compact mono- or binuclear complexes are most effective (Figure 2).

 

Figure 2. Upper: T1-weighted phantom MR-images at 3 and 7 T on selected polynuclear complexes highlighting the effective signal enhancement of the new MRI probes at clinically relevant magnetic field strengths in comparison to the commercial MRI agent ProHance®. Lower: Signal enhancement (298 K) of Gd3L3, Gd4L4 and Gd6L6 compared to Prohance at 1, 3 and 7 T.

The results of this study allow identifying the most effective strategy for optimizing the CAs, each suited to a well-defined range of applied magnetic field strength.

 

Mauro Botta is full professor of Inorganic Chemistry in the Department of Sciences and Technological Innovation at the University of Eastern Piedmont (Italy). He received the “Laurea” cum laude in Chemistry at the University of Turin in 1985. His scientific interests have focused on the use of NMR techniques for the characterization of inorganic systems, starting from organometallic clusters and then moving on the complexes of the f-elements. Recipient of the “Raffaello Nasini” gold medal award for Inorganic Chemistry of the Italian Chemical Society and of the “GIDRM gold medal for magnetic resonance”. He has published over 280 papers (index H = 63; citation: 12800) and several book chapters on these topics and filed 5 patents.

 

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Tailoring MOFs and COFs for artificial photosynthesis

Over a couple of decades, solar-to-chemical energy conversion—so called “artificial photosynthesis”—has been regarded as a holy grail that enables a carbon-neutral production and use of fuels and chemicals. In principle, various kinds of chemicals can be produced using semiconducting materials or photosensitizers with a proper bandgap and band-edge positions for target redox reactions. Despite conceptual simplicity and elegance, the realization of artificial photosynthesis is a highly challenging task. Its realization requires not only the development of various functional components such as light-harvesting, charge separation/ transporting, and catalytically active materials, but also their rational and precise assembly into an integrated device. Conventional solar-to-chemical conversion devices are mainly composed of inorganic materials and suffer from low efficiency and poor stability issues. These issues originate from the intrinsic problems of conventional inorganic materials, such as low absorption coefficient, high recombination of charge carriers, low electrical conductivity, poor catalytic activity. Furthermore, they have limited flexibility in engineering their physicochemical properties compared to organic materials.

Figure 1. Solar-to-chemical energy conversion by (a) powder-type photocatalysts and (b) photoelectrochemical (PEC) cells.

On the other hand, porous reticular materials such as metal organic frameworks (MOFs) and covalent organic frameworks (COFs) are recently drawing huge attention from researchers as promising functional materials. The structure and properties of MOFs and COFs can be tailored by employing various metal nodes and/or organic linkers, introducing additional functional groups, and employing different symmetry combinations, even with similar building blocks. These have led to the boom of studies about their design and synthesis for various applications such as catalysis, separation, sensing, etc.

Figure 2. Schematic illustration of the structure and properties of MOFs and COFs.

Recently, Prof. Jungki Ryu, Hyunwoo Kim, and Nayeong Kim at Ulsan National Institute of Science and Technology (UNIST) reported a comprehensive review paper especially about the application of MOFs and COFs in solar-to-chemical energy conversion. Porous structure and readily tunable physicochemical properties of MOFs and COFs can be highly beneficial to improve light absorption, charge separation, and access to reactants. As a result, they have been employed as diverse functional components for various target photo-reactions, such as hydrogen evolution reaction, oxygen evolution reaction, and CO2 reduction reaction. To help readers readily understand recent progress and challenges in the application of MOFs and COFs for solar-to-chemical energy conversion, they have organized more than 200 recent studies on the basis of their function and target reaction in chronological order. In addition, they reviewed the application of MOFs and COFs parallelly to provide insights for researchers. For example, one can find similar strategies employed for their application and also expect future research directions for relatively new COFs based on the research progress for MOFs. Lastly, they pointed out that further studies are required especially for the growth of MOF and COF thin films to make more significant research progress in the application of MOFs and COFs for artificial photosynthesis.

Jungki Ryu is an associate professor in the UNIST School of Energy and Chemical Engineering. He received his bachelor’s and PhD degrees in Materials Science and Engineering from Yonsei University in 2006 and Korea Advanced Institute of Science and Technology (KAIST) in 2011, respectively. Before joining UNIST in 2014, he had worked as a postdoctoral associate at the Massachusetts Institute of Technology for 3 years. He is currently interested in designing innovative electrochemical and photoelectrochemical devices inspired by nature for a sustainable future. Currently, he is the author of more than 50 articles indexed by SCI(E) and cited over 3,000 times with an H-index of 28.

Homepage: https://www.bioinspired-materials.com/

Twitter account: @bfml_unist, @jungki1981

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Copper catalysts for photo- and electro-catalytic hydrogen production

The development of carbon neutral, or better still carbon zero (H2) future fuels with production driven by green energy (renewables, such as solar, wind or wave generated energy) is an urgent necessity. To be cost competitive, green production of hydrogen requires long lived, high activity catalysts made from inexpensive, earth abundant metal ions.

 

Over the last few decades, various earth-abundant molecular cobalt, iron and nickel catalysts have exhibited activity for HER under photo- and electro-catalytic conditions. Prior to this study only 15 molecular copper complexes had been tested as catalysts for the H2 evolving reaction (HER) under either photo or electro-catalytic conditions.

 

Recently, Abdullah Abudayyeh in the group of Sally Brooker at the University of Otago and collaborators Garry Hanan and Olivier Scott at the University of Montreal reported the results of testing three copper(II) complexes – with a range of geometries, from square planar 1 to square pyramidal 2 and trigonal bipyramidal 3 (Figure 1) – as catalysts for HER under both photo- and electro-catalytic conditions.

Figure 1.  Right: Square planar 1 (pink), square pyramidal 2 (red) and trigonal bipyramidal 3 (green) copper(II) complexes. Left: HER electrocatalysis data shows that only square planar([CuIILEt]BF4 is, or forms, a good electrocatalyst for HER, and that it is still active after 6 hours. Black line = control.

The research team showed that under photocatalytic conditions the 3 copper complexes have modest turnover numbers (TON=460-620), but the control, using Cu(BF4)2, had a higher TON (740), and the blank (no copper) also had significant activity (TONequiv=290). So this is a cautionary tale: whilst these complexes initially appeared to be promising catalysts for photocatalytic HER, running the control and blank – studies often not reported – shows otherwise.

 

Hence the team changed focus and tested all three copper complexes as HER electrocatalysts in MeCN/acetic acid solution (Figure 1). The macrocyclic square planar complex, [CuIILEt]BF4 (1) (Figure 1, pink), is shown to be, or to form, an effective and stable electrocatalyst for HER in MeCN with acetic acid as the proton source (TON = 12.5 over six hours at -1.6 V vs 0.01 M AgNO3/Ag; at 100 mVs-1, Ecat/2=-1.64 V so overpotential necessary for catalysis=0.23 V), whilst the other two complexes, 2 and 3, had activities similar that of the control.

 

Preliminary ‘rinse and repeat’ and ‘drop of Hg’ tests – for the formation of catalytically active heterogeneous deposit on the glassy carbon working electrode or nanoparticles, respectively – are consistent with homogeneous catalysis by 1. But the authors note that it is distinctly possible that these initial test results are ‘false negatives’ (they recommend reading the excellent review by J. Dempsey on this topic), as the CVs show a stripping process consistent with the deposition of metallic copper on the electrode, so it remains possible that a heterogeneous catalytically active species forms, but is not seen as it is unstable in air or falls off the electrode during the rinse step.

 

Future studies on 1 aim to determine whether the catalytically active species is homogeneous or heterogeneous, but regardless of the outcome, the observed HER performance is promising and long lived.

 

Left to right: Abdullah, Olivier, Humphrey, Garry and Sally

 

 

Abdullah M. Abudayyeh completed his BSc in Chemistry in Mu’tah University, Jordan. He received his MSc in organic chemistry from the University of Jordan, working on Schiff base amidine systems. On successful completion of his MSc he worked as a chemistry teacher at the United Nations secondary school in Jordan for five years and then in a couple of other schools in Jordan, before moving to the University of Bradford, UK, in 2015. There he pursued his second MSc degree, developing thin films of Zr-based metal-organic frameworks (MOFs) on a conductive FTO substrate, which he completed with distinction. He then moved to Dunedin, New Zealand, to take up a University of Otago PhD scholarship in Professor Sally Brooker’s research group, working on coordination complexes as catalysts for the hydrogen evolution reaction (HER).

 

Olivier Schott graduated with the Bachelor of Chemistry and two Masters: Supramolecular and Molecular Chemistry and Chemical Physics and Materials at Université de Strasbourg (France). His first steps in research with Professor Julve and Professor Kurmoo were related to the synthesis of supramolecular inorganic architectures for the study of magnetic exchange interactions between transition metals. During an international student exchange, he joined the Green Energy Group of Université de Montreal (Canada) under the direction of Professor Garry S. Hanan and became a PhD candidate. In the domain of molecular artificial photosynthesis, he is investigating various poly-metallic N-rich supramolecular systems for the photocatalysis of solar fuels. In 2019, he got a PhD fellowship: Fonds Québécois de la Recherche sur la Nature et les Technologies (FRQNT) and received three times the J. Armand Bombardier Excellence Award.

 

 

Humphrey L. C. Feltham obtained his MSc and PhD (both with distinction) in Chemistry from the University of Otago under the supervision of Professor Sally Brooker, working on tetrametallic 3d-4f macrocyclic Single Molecule Magnets. From 2012-2018 he was a research associate in Professor Brooker’s team, working on projects ranging from the tuning of spin crossover complexes to the covalent immobilisation of magnetically and catalytically interesting complexes onto Au nanoparticles and PEDOT films. In 2019, he joined the chemistry team at Ligar Limited Partnership (www.ligar.nz), developing novel polymers for the removal or recovery of valuable or unwanted molecules from a variety of solutions. eg. removing smoke taints from wine, recovering bioactive molecules from plant extracts, remediating toxins from drinking water, and modifying flavour of beverages.

 

Professor Garry S. Hanan received his Ph. D. degree from l’Université Louis Pasteur in Strasbourg, France, in 1995.  After working in at the Max-Plank Institut fuer Kohlenforschung (1996-1997) and l’Università di Messina (1997-1998) as a post-doctoral Fellow, he started his academic career at the University of Waterloo in 1998 (Assistant Professor). In 2002 he moved to the Université de Montréal (as Associate Professor) where he is currently a Full Professor.  He was recently awarded an Accelerator Grant and is currently the leader of a Strategic Project, both funded by the Natural Sciences and Engineering Research Council of Canada (NSERC).  His current research interests include metal-assembled complexes, inorganic photochemistry, and photocatalytic hydrogen production.

 

Professor Sally Brooker (MNZM, FRSNZ, FNZIC, FRSC) studied at the University of Canterbury, New Zealand [BSc(Hons) first class; PhD with Professor Vickie McKee]. After postdoctoral research at Georg-August-Universität Göttingen, Germany, with Professor George M. Sheldrick, she took up a Lectureship at the University of Otago where she is now a full Professor and Sesquicentennial Distinguished Chair. She has been the recipient of numerous awards, most recently including a 2017 Queens Birthday Honour for services to science (MNZM), the 2017 Hector Medal (RSNZ) and 2017 Burrows Award (RACI). Her research interests concern the design, synthesis and full characterisation of, primarily paramagnetic, di- and poly-metallic complexes of transition metal and lanthanide ions with polydentate acyclic and macrocyclic ligands, as these have interesting redox, magnetic, catalytic and photophysical properties (otago.ac.nz/brooker).

 

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Recent research on 2D materials– A collection of articles from Frontiers Journals

We are delighted to share with you a collection of articles from Inorganic Chemistry Frontiers and Materials Chemistry Frontiers to showcase the key findings and breakthroughs in the field of 2D materials recently. This collection is free to access till Jun 14 2020.

Reviews


Ultrathin two-dimensional metallic nanomaterials
Yang Ma, Bin Li and Shubin Yang
Mater. Chem. Front., 2018,2, 456-467
https://doi.org/10.1039/C7QM00548B

Engineering two-dimensional layered nanomaterials for wearable biomedical sensors and power devices
Xianyi Cao, Arnab Halder, Yingying Tang, Chengyi Hou, Hongzhi Wang, Jens Øllgaard Duus and Qijin Chi
Mater. Chem. Front., 2018,2, 1944-1986
https://doi.org/10.1039/C8QM00356D

Research articles


Highly oriented two-dimensional formamidinium lead iodide perovskites with a small bandgap of 1.51 eV
Jielin Yan, Weifei Fu, Xinqian Zhang, Jiehuan Chen, Weitao Yang, Weiming Qiu, Gang Wu, Feng Liu, Paul Heremans and Hongzheng Chen
Mater. Chem. Front., 2018,2, 121-128
https://doi.org/10.1039/C7QM00472A

Electrochemical sensor based on novel two-dimensional nanohybrids: MoS2 nanosheets conjugated with organic copper nanowires for simultaneous detection of hydrogen peroxide and ascorbic acid
Dapeng Li, Xueying Liu, Ran Yi, Jiaxian Zhang, Zhiqiang Su and Gang Wei
Inorg. Chem. Front., 2018,5, 112-119
https://doi.org/10.1039/C7QI00542C

A new two-dimensional layered germanate with in situ embedded carbon dots for optical temperature sensing
Jiancong Liu, Xiaoyan Ren, Yan Yan, Ning Wang, Shuang Wang, Hongyue Zhang, Jiyang Li and Jihong Yu
Inorg. Chem. Front., 2018,5, 139-144
https://doi.org/10.1039/C7QI00602K

A 2D porous pentiptycene-based MOF for efficient detection of Ba2+ and selective adsorption of dyes from water
Minghui Zhang, Ziqiang Qi, Yang Feng, Bingbing Guo, Yujian Hao, Zhuo Xu, Liangliang Zhang and Daofeng Sun
Inorg. Chem. Front., 2018,5, 1314-1320
https://doi.org/10.1039/C8QI00098K

Constructing a direct Z-scheme photocatalytic system based on 2D/2D WO3/ZnIn2S4 nanocomposite for efficient hydrogen evolution under visible light
Pengfei Tan, Anquan Zhu, Lulu Qiao, Weixuan Zeng, Yongjin Ma, Haigang Dong, Jianping Xie and Jun Pan
Inorg. Chem. Front., 2019,6, 929-939
https://doi.org/10.1039/C8QI01359D

Two-dimensional MoS2 modified using CoFe2O4 nanoparticles with enhanced microwave response in the X and Ku band
Xiaoqing Cui, Wei Liu, Weihua Gu, Xiaohui Liang and Guangbin Ji
Inorg. Chem. Front., 2019,6, 590-597
https://doi.org/10.1039/C8QI01304G

Negatively charged 2D black phosphorus for highly efficient covalent functionalization
Lei Zhang, Lin-Feng Gao, Liuxiao Li, Chen-Xia Hu, Qi-Qi Yang, Zhi-Yuan Zhu, Rui Peng, Qiang Wang, Yong Peng, Jun Jin and Hao-Li Zhang
Mater. Chem. Front., 2018,2, 1700-1706
https://doi.org/10.1039/C8QM00237A

Core–shell assembly of carbon nanofibers and a 2D conductive metal–organic framework as a flexible free-standing membrane for high-performance supercapacitors
Shihang Zhao, Huihui Wu, Yanli Li, Qin Li, Jiaojiao Zhou, Xianbo Yu, Hongmei Chen, Kai Tao and Lei Han
Inorg. Chem. Front., 2019,6, 1824-1830
https://doi.org/10.1039/C9QI00390H

Two-dimensional SnS2 nanosheets exfoliated from an inorganic–organic hybrid with enhanced photocatalytic activity towards Cr(VI) reduction
Yongping Liu, Xihong Mi, Jixiang Wang, Ming Li, Dayong Fan, Huidan Lu and Xiaobo Chen
Inorg. Chem. Front., 2019,6, 948-954
https://doi.org/10.1039/C9QI00020H

Organic cation directed hybrid lead halides of zero-dimensional to two-dimensional structures with tunable photoluminescence properties
Cheng-Yang Yue, Hai-Xiao Sun, Quan-Xiu Liu, Xin-Ming Wang, Zhao-Shuo Yuan, Juan Wang, Jia-Hang Wu, Bing Hu and Xiao-Wu Lei
Inorg. Chem. Front., 2019,6, 2709-2717
https://doi.org/10.1039/C9QI00684B

Ultrathin 2D Cu-porphyrin MOF nanosheets as a heterogeneous catalyst for styrene oxidation
Yawen Xiao, Wenxiao Guo, Huanhuan Chen, Hongfeng Li, Xiujie Xu, Peng Wu, Yu Shen, Bing Zheng, Fengwei Huo and Wei David Wei
Mater. Chem. Front., 2019,3, 1580-1585
https://doi.org/10.1039/C9QM00201D

Pairing 1D/2D-conjugation donors/acceptors towards high-performance organic solar cells
Jiayu Wang, Yiqun Xiao, Wei Wang, Cenqi Yan, Jeromy Rech, Mingyu Zhang, Wei You, Xinhui Lu and Xiaowei Zhan
Mater. Chem. Front., 2019,3, 276-283
https://doi.org/10.1039/C8QM00512E

Sandwich membranes through a two-dimensional confinement strategy for gas separation
Zixi Kang, Sasa Wang, Rongming Wang, Hailing Guo, Ben Xu, Shou Feng, Lili Fan, Liangkui Zhu, Wenpei Kang, Jia Pang, Hanyi Sun, Xinxin Du, Minghui Zhang and Daofeng Sun
Mater. Chem. Front., 2018,2, 1911-1919
https://doi.org/10.1039/C8QM00351C

A chemical sensor for CBr4 based on quasi-2D and 3D hybrid organic–inorganic perovskites immobilized on TiO2 films
Pavlos Nikolaou, Anastasia Vassilakopoulou, Dionysios Papadatos, Emmanuel Topoglidis and Ioannis Koutselas
Mater. Chem. Front., 2018,2, 730-740
https://doi.org/10.1039/C7QM00550D

Applying surface strain and coupling with pure or N/B-doped graphene to successfully achieve high HER catalytic activity in 2D layered SnP3-based nanomaterials: a first-principles investigation
Ran Zhang, Guangtao Yu, Yang Gao, Xuri Huang and Wei Chen
Inorg. Chem. Front., 2020,7, 647-658
https://doi.org/10.1039/C9QI01368G

ArticleA 2D/2D graphitic carbon nitride/N-doped graphene hybrid as an effective polysulfide mediator in lithium–sulfur batteries
Junsheng Ma, Mingpeng Yu, Huanyu Ye, Hongquan Song, Dongxue Wang, Yanting Zhao, Wei Gong and Hong Qiu
Mater. Chem. Front., 2019,3, 1807-1815
https://doi.org/10.1039/C9QM00228F

Construction of two-dimensional supramolecular nanostructure with aggregation-induced emission effect via host–guest interactions
Hui Liu, Qingyan Pan, Chenyu Wu, Jing Sun, Tao Zhuang, Tongling Liang, Xueluer Mu, Xianfeng Zhou, Zhibo Li and Yingjie Zhao
Mater. Chem. Front., 2019,3, 1532-1537
https://doi.org/10.1039/C9QM00243J

Interfacial synthesis of ultrathin two-dimensional 2PbCO3·Pb(OH)2 nanosheets with high enzyme mimic catalytic activity
Danbo Wang, Xiaonan Kan, Chenyu Wu, Xiaohuan Lin, Haiyan Zheng, Kuo Li, Jikuan Zhao and Yingjie Zhao
Inorg. Chem. Front., 2019,6, 498-503
https://doi.org/10.1039/C8QI01196F

A two-dimensional bilayered Dion–Jacobson-type perovskite hybrid with a narrow bandgap for broadband photodetection
Dongying Fu, Jianrong Yuan, Shichao Wu, Yunpeng Yao, Xinyuan Zhang and Xian-Ming Zhang
Inorg. Chem. Front., 2020,7, 1394-1399
https://doi.org/10.1039/C9QI01540J

A facile fabrication of 1D/2D nanohybrids composed of NiCo-hydroxide nanowires and reduced graphene oxide for high-performance asymmetric supercapacitors
Xu Zhang, Qiuyu Fan, Siyu Liu, Ning Qu, He Yang, Man Wang and Juan Yang
Inorg. Chem. Front., 2020,7, 204-211
https://doi.org/10.1039/C9QI00681H

A 2D layer network assembled from an open dendritic silver cluster Cl@Ag11N24 and an N-donor ligand
Xiao-Yu Li, Hai-Feng Su and Jian Xu
Inorg. Chem. Front., 2019,6, 3539-3544
https://doi.org/10.1039/C9QI01100E

Layered Ti3C2 MXene modified two-dimensional Bi2WO6 composites with enhanced visible light photocatalytic performance
Danxia Zhao and Chun Cai
Mater. Chem. Front., 2019,3, 2521-2528
https://doi.org/10.1039/C9QM00570F

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Congratulations to our highly cited board members!

We are proud to announce that 13 of Inorganic Chemistry Frontiers Board members are recognized in Clarivate Analytics list of Highly Cited Researchers for 2019, ranking them among the top 1% most cited for their subject field and publication year.

The board members are:

Editorial Board

Song Gao, South China University of Technology, China
Jun Chen, Nankai University, China
Nanfeng Zheng, Xiamen University, China

Advisory Board

Christopher J Chang, University of California, Berkeley, USA
Xiao-Ming Chen, Sun Yat-Sen University, China
Yi Cui, Stanford University, USA
Xile Hu, École Polytechnique Fédérale de Lausanne, Switzerland
Mercouri Kanatzidis, Northwestern University, USA
Yadong Li, Tsinghua University, China
Wenbin Lin, University of Chicago, USA
Yi Xie, University of Science and Technology of China, China
Qichun Zhang, Nanyang Technological University, Singapore
Hong-Cai Joe Zhou, Texas A&M University, USA

 

Below are a few of our picks from their publications in Frontiers Journals. Access is free to all these highlighted papers until 31 Jan 2020!

Multiple magnetic relaxation pathways in T-shaped N-heterocyclic carbene-supported Fe(i) single-ion magnets
Yin-Shan Meng, Zhengwu Ouyang, Mu-Wen Yang, Yi-Quan Zhang, Liang Deng*, Bing-Wu Wang* and Song Gao*
Inorg. Chem. Front., 2019,6, 1050-1057
http://dx.doi.org/10.1039/C9QI00073A

single-molecule magnet
Yin-Shan Meng*, Yu-Sen Qiao, Mu-Wen Yang, Jin Xiong, Tao Liu, Yi-Quan Zhang, Shang-Da Jiang, Bing-Wu Wang* and Song Gao*
Inorg. Chem. Front., 2019, Advance Article
http://dx.doi.org/10.1039/C9QI01252D

Selective hydrogenation of CO2 over a Ce promoted Cu-based catalyst confined by SBA-15
Xiaosong Hu, Chaoyue Zhao, Qingxin Guan, Xin Hu, Wei Li* and Jun Chen
Inorg. Chem. Front., 2019,6, 1799-1812
http://dx.doi.org/10.1039/C9QI00397E

High-performance rechargeable aqueous Zn-ion batteries with a poly(benzoquinonyl sulfide) cathode
Gulbahar Dawut, Yong Lu, Licheng Miao and Jun Chen*
Inorg. Chem. Front., 2018,5, 1391-1396
http://dx.doi.org/10.1039/C8QI00197A

N-Methyl-2-pyrrolidone as an excellent coordinative additive with a wide operating range for fabricating high-quality perovskite films
Fangwen Cheng, Xiaojing Jing, Ruihao Chen, Jing Cao, Juanzhu Yan, Youyunqi Wu, Xiaofeng Huang, Binghui Wu* and Nanfeng Zheng*
Inorg. Chem. Front., 2019,6, 2458-2463
http://dx.doi.org/10.1039/C9QI00547A

A single palladium site catalyst as a bridge for converting homogeneous to heterogeneous in dimerization of terminal aryl acetylenes
Chao Zhao, Haizhu Yu, Jing Wang, Wei Che, Zhijun Li, Tao Yao, Wensheng Yan, Min Chen, Jian Yang, Shiqiang Wei, Yuen Wu* and Yadong Li
Mater. Chem. Front., 2018,2, 1317-1322
http://dx.doi.org/10.1039/C8QM00095F

Manganese-mediated reductive amidation of esters with nitroarenes
Chi Wai Cheung*, Ni Shen, Shao-Peng Wang, Asim Ullah, Xile Hu and Jun-An Ma*
Org. Chem. Front., 2019,6, 756-761
http://dx.doi.org/10.1039/C8QO01405A

Recent progress in ligand-centered homogeneous electrocatalysts for hydrogen evolution reaction
Geng-Geng Luo*, Hai-Lin Zhang, Yun-Wen Tao, Qiao-Yu Wu, Dan Tian and Qichun Zhang*
Inorg. Chem. Front., 2019,6, 343-354
http://dx.doi.org/10.1039/C8QI01220B

New synthetic strategies to prepare metal–organic frameworks
Peng Li, Fang-Fang Cheng, Wei-Wei Xiong* and  Qichun Zhang*
Inorg. Chem. Front., 2018,5, 2693-2708
http://dx.doi.org/10.1039/C8QI00543E

Cost-effective synthesis and solution processing of porous polymer networks through methanesulfonic acid-mediated aldol triple condensation
Zi-Hao Guo, Chenxu Wang, Qiang Zhang, Sai Che, Hong-Cai Zhou and Lei Fang*
Mater. Chem. Front., 2018,2, 396-401
http://dx.doi.org/10.1039/C7QM00485K

A flexible thioether-based MOF as a crystalline sponge for structural characterization of liquid organic molecules
Xin-Yu Yang, Shuai Yuan, Jun-Sheng Qin, Christina Lollar, Ali Alsalme* and Hong-Cai Zhou*
Mater. Chem. Front., 2017,1, 1764-1767
http://dx.doi.org/10.1039/C7QM00152E

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