Meeting of Inorganic Chemists Recently Appointed

Chemical CommunicationsChemical Science and Dalton Transactions are pleased to sponsor the 2018 Meeting of Inorganic Chemists Recently Appointed (MICRA). This biennial event is being organised by Dr Timothy Easun and Dr Rebecca Melen from Cardiff University, and is taking place on 10 – 12 September 2018 at Cardiff University in Wales.

The meeting brings together junior inorganic chemistry academics from across the UK to help aid their development into independent researchers through networking and exchanging experiences. MICRA 2018 will have exciting talks from experts such as Paul Saines (University of Kent), Timothy Easun (Cardiff University) and Rebecca Melen (Cardiff University).

For more information and to register, go to: https://www.micra2018.com/

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ChemComm poster prize winner at the 16th Symposium for Host-Guest and Supramolecular Chemistry

The 16th Symposium for Host-Guest and Supramolecular Chemistry was held on 2 – 3 June 2018 at the Tokyo University of Science in Japan.

This annual symposium covers all aspects of the chemical sciences related to molecular recognition and supramolecular chemistry, including the discussion of topics around intermolecular interactions. The event included a special lecture by Dr Shigeki Sasaki and invited lectures by Dr Takashi Hayashi and Dr Katsuhiko Ariga.

ChemComm is delighted to announce that the ChemComm poster prize was awarded to Hiroshi Koganezawa from the Tokyo University of Science for a poster entitled ‘Synthesis of [2]Rotaxanes with Spirofluorene and Pyrrole Moieties’.

Well done Hiroshi from everyone at ChemComm!

 

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Better Make It A Double

Synthesizing nanomaterials consisting of two-particle pairs, or dimers, is no longer a headache. Hongyu Chen and coworkers from Nanjing Tech University, China recently developed a protocol that can produce gold dimers with a record high yield. This breakthrough is published in Chem. Commun.

Dimers are suitable platforms to study the effects of particle-particle interactions on the electrical and optical properties of the constituent materials. Unfortunately, no conventional synthesis methods to exclusively produce dimers from single particles have been successful. This is because of the uncontrollable particle-aggregation rate that leads to the formation of multi-particle clusters. Therefore, how to couple single particles into dimers without triggering their further aggregation has become a tough nut to crack.

Chen and coworkers found a solution by developing a polymer-assisted method that generates gold dimers with high yield. Firstly, they encapsulated individual gold nanoparticles with polymer shells made of polystyrene-b-poly(acrylic acid). Under optimized conditions, the gold nanoparticles were mostly coupled into dimers (Figure 1), achieving a dimer yield of 65%. This is the highest dimer yield achieved for one-step synthesis methods.

Figure 1. (a) A transmission electron microscopy (TEM) image of the polymer-encapsulated gold single particles. (b) A TEM image and (c) a scanning electron microscopy image of the synthesized gold dimers. All scale bars are 200 nm.

The key to this success is due to three factors: temperature, solvent composition and acid concentration. All these factors can change the strength of the repulsion force among the polymer shells. The force must be meticulously tuned to a level that is weak enough to induce 1-to-1 coupling, but strong enough to prevent 1-to-multiple or multiple-to-multiple aggregation. Through a set of control experiments, the authors identified the optimal conditions to be 60 oC, dimethylformamide/water (v/v)=6:1 and 5 mM of hydrochloric acid.

The method demonstrated herein could be extended to other particles. It may also inspire versatile synthesis strategies towards complex nanostructures with high selectivity.

 

To find out more please read:

Controllable Oligomerization: Defying Step-Growth Kinetics in the Polymerization of Gold Nanoparticles

Xuejun Cheng, Gui Zhao, Yan Lu, Miao Yan, Hong Wang and Hongyu Chen

Chem. Sci., 2018, DOI: 10.1039/C8CC03424A

 

About the blogger:

Tianyu Liu obtained his Ph.D. (2017) in Physical Chemistry from University of California, Santa Cruz in the United States. He is passionate about scientific communication to introduce cutting-edge research to both the general public and scientists with diverse research expertise. He is a blog writer for Chem. Commun. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

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ChemComm poster prize winner at the 2018 European Materials Research Society Spring Meeting

The 2018 European Materials Research Society (EMRS) Spring Meeting was held from the 18th – 22nd June in the Strasbourg Convention Centre in France.

The EMRS Spring Meeting is the society’s major conference and covers all aspects of materials science including energy and environment, biomaterials, semiconductors, nanomaterials, functional materials, and materials processing and characterization. It offers on average 25 topical symposia and is widely recognised as being of the highest international significance, with approximately 2,500 attendees every year.

ChemComm is proud to announce that the ChemComm poster prize was awarded to Dr Manal Alkhamisi from the University of Nottingham (School of Physics and Astronomy) for ‘The Growth and Fluorescence of Phthalocyanine Monolayers and Thin Films on Hexagonal Boron Nitride’. Manal was awarded the prize by ChemComm Associate Editor Steven De Feyter.

Well done Manal!

 

ChemComm Associate Editor Steven De Feyter (left) awarding the poster prize to Dr Manal Alkhamisi (right)

 

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HOT ChemComm articles for May

All of the referee-recommended articles below are free to access until 6th July 2018.

A quasi-solid-state and self-powered biosupercapacitor based on flexible nanoporous gold electrodes
Xinxin Xiao and Edmond Magner
Chem. Commun., 2018, 54, 5823-5826
DOI: 10.1039/C8CC02555J, Communication

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Late stage modifications of P-containing ligands using transition-metal-catalysed C–H bond functionalisation
Zhuan Zhang, Pierre H. Dixneuf and Jean-François Soulé
Chem. Commun., 2018, Advance Article
DOI: 10.1039/C8CC02821D, Feature Article

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A novel three-fluorophore system as a ratiometric sensor for multiple protease detection
Yana Okorochenkova, Martin Porubský, Sandra Benická and Jan Hlaváč
Chem. Commun., 2018, Advance Article
DOI: 10.1039/C8CC01731J, Communication

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The environmental-sensitivity of a fluorescent ZTRS–Cd(II) complex was applied to discriminate different types of surfactants and determine their CMC values
Fei Deng, Shuangshuang Long, Qinglong Qiao and Zhaochao Xu
Chem. Commun., 2018, Advance Article
DOI: 10.1039/C8CC03888K, Communication

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An intrinsically compressible and stretchable all-in-one configured supercapacitor
Mengmeng Hu, Jiaqi Wang, Jie Liu, Jiaheng Zhang, Xing Ma and Yan Huang
Chem. Commun., 2018, Advance Article
DOI: 10.1039/C8CC03375G, Communication

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Paraffinic metal–organic polyhedrons: solution-processable porous modules exhibiting three-dimensional molecular order
Kenichiro Omoto, Nobuhiko Hosono, Mika Gochomori and Susumu Kitagawa
Chem. Commun., 2018, Advance Article
DOI: 10.1039/C8CC03705A, Communication

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Come for the colour changing crystals, stay for the science

Synthesis of copper bimetallic complexes from imidazolyl ligands, and the solvatochromic materials formed upon crystallization and solvent guest-exchange. The solvatochromic behaviour was quantified with visible-region diffuse reflectance spectra.

Synthesis of copper bimetallic complexes from imidazolyl ligands, and the solvatochromic materials formed upon crystallization and solvent guest-exchange. The solvatochromic behaviour was quantified with visible-region diffuse reflectance spectra.

During the first inorganic chemistry course I took during my undergraduate degree, our professor started the class by passing around some mineral samples, promising us that if we pursued the chemistry of metals we could work with beautifully coloured crystals every day. At the time, colour seemed like such a trite detail amongst the complexity of the subject. Why would you choose a field of study based on something so simple? Well, after a PhD dominated by pale yellow oils, I think I get it now.

Nikolayenko and Barbour at the University of Stellenbosch in South Africa bring us colour! The authors synthesised organometallic copper complexes, which crystallise to form porous single crystals that drastically change colour upon absorption of various solvents. The authors investigated the solvatochromic mechanism using X-ray crystallography, EPR, UV-visible spectroscopy and DFT calculations. Solvatochromic materials are not just made to look pretty; they have potential to be used as sensitive, selective and recyclable sensors to detect solvent vapours with useful applications in industrial process risk management, chemical threat detection and environmental monitoring.

The researchers synthesised a series of complexes comprised of a bidentate ligand with 2-methylimidazolyl groups coordinated to copper(II) ions. The complexes stack to form channels in the crystal, capable of trapping solvent molecules to give different coloured crystals: DMSO and THF-containing crystals are green (λmax = 574 nm and 540 nm, respectively), those containing acetonitrile are red (λmax = 624 nm), and crystals trapping acetone, ether and pentane are yellow (λmax = 588), orange (λmax = 598 nm) and red/brown (λmax = 592 nm), respectively.

The authors revealed a correlation between the size of the solvent guest, coordination geometry of the copper complex, and the ligand field splitting. Small guests such as acetonitrile minimally perturb the metallocyclic framework, preserving a rhombic ligand field geometry (large δxy of g values in the EPR spectrum), small ligand d-orbital splitting and red-shifted optical spectra. Large guests such as THF have the opposite effect, giving ligand field geometries approaching tetragonal (small δxy), large ligand field d-orbital splitting and blue-shifted optical spectra.

By delving into the complexity beneath a seemingly simple phenomenon, Nikolayenko, Barbour and their co-workers have shown using a series of single-crystal complexes that there is nothing simple about colour (and nothing trite about detail).

To find out more please read:

Supramolecular solvatochromism: mechanistic insight from crystallography, spectroscopy, and theory

Varvara I. Nikolayenko, Lisa M. van Wyk, Orde Q. Munro, Leonard J. Barbour.
Chem. Commun., 2018, Advance Article
DOI: 10.1039/c8cc02197j

About the author

Zoë Hearne is a PhD candidate in chemistry at McGill University in Montréal, Canada, under the supervision of Professor Chao-Jun Li. She hails from Canberra, Australia, where she completed her undergraduate degree. Her current research focuses on transition metal catalysis to effect novel transformations, and out of the lab she is an enthusiastic chemistry tutor and science communicator.

 

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Pt3Ni-Coated Palladium Nano-branches Outperformed Pt in Catalyzing Ethanol Oxidation

Researchers in China recently developed a new Pd-based catalyst that outperformed Pt, the benchmark catalyst for electrochemical oxidation of ethanol. This catalyst, synthesized by a one-pot chemical reduction method, consists of branched Pd nanocrystals coated with thin Pt3Ni shells.

The ethanol oxidation reaction (EOR) is a typical anode reaction that drives the energy output from fuel cells. Due to its intrinsically slow kinetics, the reaction requires proper EOR catalysts to facilitate the oxidation. Pt-based materials are highly active in promoting EOR, but the scarcity of Pt leads to high costs and demands efficient methods to recycle these materials. In addition, the instable catalytic activity of Pt significantly reduces the lifetime of EOR catalysts containing Pt. Clearly, developing inexpensive EOR catalysts with comparable performance to Pt is meaningful for the affordability and durability of fuel cells.

A research team led by Shuifen Xie at Huaqiao University and Shenzhen Research Institute of Xiamen University in China, have demonstrated a one-pot chemical reduction method of a novel EOR catalyst. This catalyst is made of Pt3Ni-coated Pd nanocrystals as shown in Figure 1. There are three main advantages for this catalyst over the benchmark Pt: Firstly, the core material Pd is more affordable. Secondly, the ultrathin Pt-alloy coating, Pt3Ni, contains relatively less Pt and is reported to exhibit high EOR catalytic activity. Thirdly, the little lattice mismatch between Pt and Pd allows seamless integration of the two metals that is beneficial to preserve the structural integrity and ensure excellent durability.

Figure 1. (a) The schematic illustration showing the key steps of the one-pot chemical reduction method. The catalyst is formed via consecutive reduction of Pd2+, Pt2+ and Ni2+ to Pd nano-branches, Pt nanoparticles and Pt3Ni coatings, respectively. (b) A TEM image of a representative morphology of a branched nanocrystal. (c) Elemental mappings depict that Pt and Ni elements exist mainly in the shell while Pd is in the core.

Electrochemical characterizations revealed that the catalytic performance of the Pt3Ni-coated Pd nanocrystals outperformed those of two commercial catalysts: Pt/C (Pt particles supported on activated carbon) and Pd black (a fine powder elemental Pd). Figure 2a compares the linear-sweep voltammograms of the three samples. The synthesized catalyst showed appreciably enhanced oxidation current at potentials beyond 0.4 V vs. RHE. The histograms in Figure 2b clearly display that the mass activity and the specific activity of the synthesized nanocrystals are the highest. The authors ascribed the superior performance to the high surface area (42.50 m2 g-1), the ultrathin Pt3Ni coating with its {111} crystal planes exposed, and the core-shell configuration.

Figure 2. (a) Linear-sweep voltammograms of the synthesized catalyst (Pd@Pt3Ni/C), Pt/C and Pd black. (b) The comparison of mass activity (i.e. oxidation current normalized to the masses of the catalysts) and specific activity (i.e. oxidation current normalized to the areas of the catalysts) of Pd@Pt3Ni/C, Pt/C and Pd black.

This work signifies the feasibility of Pd-based nano-catalysts as alternatives to Pt towards catalyzing EOR. It is also expected to encourage the effort in developing a diverse array of inexpensive and high-performance catalysts for other reactions pertaining to fuel cells, including but not limited to oxidation of fuels other than ethanol and oxygen reduction reactions.

To find out more please read:

One-Pot Synthesis of Pd@Pt3Ni Core-Shell Nanobranches with Ultrathin Pt3Ni{111} Skins for Efficient Ethanol Electrooxidation

Yuanyuan Wang, Wei Wang, Fei Xue, Yong Cheng, Kai Liu, Qiaobao Zhang, Maochang Liu and Shuifen Xie

Chem. Commun., 2018, DOI: 10.1039/c8cc02816h

About the blogger:

Tianyu Liu obtained his Ph.D. (2017) in Physical Chemistry from University of California, Santa Cruz in the United States. He is passionate about scientific communication to introduce cutting-edge research to both the general public and scientists with diverse research expertise. He is a blog writer for Chem. Commun. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

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The CO2-Capturing Mechanism of Quaternary Nitrogen-Containing Polymers Revealed Experimentally

A group of scientists from Washington University at St. Louis, USA have disclosed experimentally how CO2 is captured by polymers with quaternary nitrogen cations. Using solid-state nuclear magnetic resonance (NMR), the authors established that CO2 molecules were absorbed as bicarbonate anions (HCO3).

The increasing amount of CO2 has posed a number of concerning environmental issues such as climate change, rising sea level and ocean acidification. Capturing CO2 from the atmosphere is an effective way to lower the CO2 concentration. Recently, a family of polymer absorbents containing quaternary nitrogen functional groups, termed humidity-swing polymers, have been identified as promising absorbents to absorb CO2 directly from air. However, the limited understanding of the chemical mechanism related to their CO2-capturing capability hindered the development of these promising absorbents.

In ChemComm, Yang et al. used solid-state 13C NMR to explore how CO2 molecules were captured and released. Figure 1a presents the NMR spectra of a humidity-swing polymer absorbent itself (top), upon contacting with CO2 (middle) and after releasing CO2 (bottom). The most striking feature is the appearance of an additional sharp peak at a chemical shift of 161 ppm in the middle spectrum, which did not show up in the other two spectra. The authors further studied the shape evolution of the additional peak, with respect to temperature, and concluded that the peak was due to HCO3 anions. Additionally, the authors also identified the presence of hydroxide anions in the absorbent after CO2 was released.

Figure 1. (a) The solid-state 13C NMR spectra of the humidity-swing polymeric absorbent (structure shown in the inset of the middle spectrum) itself (top), upon contacting with CO2 (middle) and after releasing CO2 (bottom). (b) The proposed pathways of how CO2 molecules interact with the quaternary-N anions of the absorbent.

The researchers then proposed the CO2 adsorption-desorption mechanism (illustrated in Figure 1b) based on the experimental results. The storage and release of CO2 depend on the humidity level of the surroundings: When the humidity is low, the polymer absorbs CO2 and forms HCO3 anions; the negative charge of HCO3 is counter-balanced by the neighboring quaternary N cations. When the humidity is increased, HCO3 anions combine with water and decompose to CO2 and hydroxide anions. This proposed pathway does not involve CO32- anions, which differs from the previously-reported mechanisms derived from theoretical simulations.

The published results represent the first set of experimental evidence elucidating how CO2 molecules interact with humidity-swing polymeric absorbents. The acquired mechanistic insight could provide valuable guidelines for the design of CO2 absorbents with ultrahigh absorption capacity.

 

To find out more please read:

Humidity-Swing Mechanism for CO2 Capture from Ambient Air
Hao Yang, Manmilan Singh and Jacob Schaefer
Chem. Commun., 2018, DOI: 10.1039/c8cc02109k

About the blogger:

Tianyu Liu obtained his Ph.D. (2017) in Physical Chemistry from University of California, Santa Cruz in United States. He is passionate about scientific communication to introduce cutting-edge research to both the general public and scientists with diverse research expertise. He is a blog writer for Chem. Commun. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

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Amanda Hargrove and Alexander Miller: Winners of the ChemComm Emerging Investigator Lectureship 2018

On behalf of the ChemComm Editorial Board, we are pleased to announce the winners of the 2018 ChemComm Emerging Investigator Lectureship – Amanda Hargrove and Alexander Miller. Our warmest congratulations to Amanda and Alexander!

 

 

Amanda Hargrove

Amanda was awarded her PhD in 2010 at the University of Texas at Austin, where she worked with Professors Eric V. Anslyn and Jonathan L. Sessler on combining recognition motifs for improved sensing and biological activity of oligosaccharides and phosphorylated molecules. During her independent career, she has received the 2014 Ralph E. Powe Junior Faculty Enhancement Award, 2015 Prostrate Cancer Foundation Young Investigator Award, 2017 Cottrell Scholar Awards and 2018 National Science Foundation CAREER Award.

She is currently an Assistant Professor at Duke University and her group works at the interface of chemistry and biology, using organic chemistry tools to study the structure and function of long noncoding RNAs.

 

 

 

 


Alexander Miller

Alexander completed his PhD in 2011 at the California Institute of Technology, where he worked on emissive monocopper amidophosphine complexes and Lewis acid-assisted reductive coupling of carbon monoxide with Professors John E. Bercaw and Jay A. Labinger. He has been awarded several honours during his independent career, including the 2014 University Research Council James Moeser Award for Distinguished Research, 2016 National Science Foundation CAREER Award and 2017 Organometallics Distinguished Author Award.

He currently has a position as an Assistant Professor at the University of North Carolina, and his group’s research focusses on the storage of solar energy in chemical fuels, proton-coupled electron transfer reactions, and hydrocarbon transformations.

 

 

 

As part of the Lectureship, Amanda and Alexander will present a lecture at three locations over the coming year, with at least one of these events taking place at an international conference. Details of the lectures will be announced in due course – keep an eye on Twitter for details.

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Read our most cited ChemComm Features from 2016 and 2017

We are showcasing our 20 most cited ChemComm Feature articles from 2016 and from 2017. This collection provides an easy way to access some of the most exciting topics of research across the chemical sciences – from materials and supramolecular chemistry through to physical chemistry and catalysis.

ALL articles are FREE to read and download until 11 June!

We hope you enjoy reading this collection! Some of the highlights are given below:

 

C6CC05568K graphical abstract, Atomic and molecular layer deposition: off the beaten track, van Ommen et al.Atomic and molecular layer deposition: off the beaten track

 

Van Bui, F. Grillo and J. R. van Ommen

Chem. Commun., 2017, 53, 45-71

DOI: 10.1039/C6CC05568K
 

 

 


C6CC08967D Graphical Abstract, Biological and related applications of pillar[n]arenes, Wang et al.

Biological and related applications of pillar[n]arenes

 

CuhaWijay Sathiyajith, Rafik Rajjak Shaikh, Qian Han, Yue Zhang, Kamel Meguellati and Ying-Wei Yang

Chem. Commun., 2017, 53, 677-696

DOI: 10.1039/C6CC08967D

 

 


C5CC08213G Graphical Abstract, Boron clusters in luminescent materials, Mukherjee and ThilagarBoron clusters in luminescent materials

 

Sanjoy Mukherjee and Pakkirisamy Thilagar

Chem. Commun., 2016, 52, 1070-1093

DOI: 10.1039/C5CC08213G

 

 

 


Fluorescent glycoprobes: a sweet addition for improved sensing

C6CC06875H Graphical Abstract, Fluorescent glycoprobes: a sweet addition for improved sensing, Xie et al.

 

Xiao-Peng He, Yi Zang, Tony D. James, Jia Li, Guo-Rong Chen
and Juan Xie

Chem. Commun., 2017, 53, 82-90

DOI: 10.1039/C6CC06875H

 

 

 


C6CC03638D Graphical Abstract, Halogen bonding anion recognition, Brown and Beer

Halogen bonding anion recognition

 

Asha Brown and Paul D. Beer

Chem. Commun., 2016, 52, 8645-8658

DOI: 10.1039/C6CC03638D

 

 

 


C6CC08820A Graphical Abstract, Long range electrostatic forces in ionic liquids, Atkin et al.Long range electrostatic forces in ionic liquids

 

Matthew A. Gebbie, Alexander M. Smith, Howard A. Dobbs, Alpha A. Lee,
Gregory G. Warr, Xavier Banquy, Markus Valtiner, Mark W. Rutland, Jacob N. Israelachvili,
Susan Perkin and Rob Atkin

Chem. Commun., 2017, 53, 1214-1224

DOI: 10.1039/C6CC08820A

 

 


C5CC08216A Graphical Abstract, Pharmaceutical cocrystals: along the path to improved medicines, Zaworotko et al.Pharmaceutical cocrystals: along the path to improved medicines

 

Naga K. Duggirala, Miranda L. Perry, Örn Almarsson and Michael J. Zaworotko

Chem. Commun., 2016, 52, 640-655

DOI: 10.1039/C5CC08216A

 

 

 


C6CC00336B Graphical Abstract, Rational control of nano-scale metal-catalysts for biomass conversion, Yan et al.Rational control of nano-scale metal-catalysts for biomass conversion

 

Yunzhu Wang,  Sudipta De  and  Ning Yan

Chem. Commun., 2016, 52, 6210-6224

DOI: 10.1039/C6CC00336B

 

 

ChemComm is renowned as the fastest publisher of articles providing information on new avenues of research, drawn from all the world’s major areas of chemical research. ChemComm is the ideal place to publish your research.

 

Submit your urgent research to ChemComm today!

 

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Be among the first to hear about the newest articles being published – Sign-up to our journal news alert to receive information about most read articles, themed issues, journal news, as well as calls for papers and invitations.

 

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