Archive for November, 2017

ChemComm Emerging Investigator Lectureship – nominations now open!

We are pleased to welcome nominations for the 2018 Emerging Investigator Lectureship for ChemComm.

All nominations must be received by Monday, 19 February 2018.

ChemComm Emerging Investigator Lectureship
• Recognises emerging scientists in the early stages of their independent academic career.
• Eligible nominees should have completed their PhD on or after the 15th September 2009.

Lectureship details
• The recipient of the lectureship will be invited to present a lecture at three different locations over a 12-month period, with at least one of these events taking place at an international conference.
• The recipient will receive a contribution of £1500 towards travel and accommodation costs for their lectures, as well as a certificate.
• The recipient will be asked to contribute a review article for the journal.

How to nominate
Self-nomination is not permitted. Nominators must send the following to the editorial team via 
chemcomm-rsc@rsc.org by Monday, 19 February 2018.
• Recommendation letter, including the name, contact details and website URL of the nominee.
• A one-page CV for the nominee, including a summary of their education, dates of key career achievements, a list of up to five of their top independent publications, total numbers of publications and patents, and other indicators of esteem, together with evidence of career independence.
• A copy of the candidate’s best publication to date (as judged by the nominator).
• Two supporting letters of recommendation from two independent referees. These should not be someone from the same institution or the candidate’s post doc or PhD supervisor.

The nominator and independent referees should comment on the candidate’s presenting skills.

Incomplete nominations or those not adhering to the above requirements will not be considered, and nominees will not be contacted regarding any missing or incorrect documents.

Selection procedure
• The editorial team will screen each nomination for eligibility and draw up a shortlist of candidates based on the nomination documents provided.
• Shortlisted candidates will be asked to provide a brief supporting statement summarising their key achievements, highlighting the impact of their work and justifying why they deserve the specific lectureship for which they have been entered.
• The recipient of the lectureship will then be selected and endorsed by a selection panel composed of members of the ChemComm Editorial Board. The winner will be announced in the first half of 2018.

NB: Please note that members of the selection panel from the ChemComm Editorial Board are not eligible to nominate, or provide references, for this lectureship.

For any queries, please contact the editorial team at chemcomm-rsc@rsc.org.

 

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Cram Lehn Pedersen Prize 2018 – call for nominations

The International Committee of the International Symposium on Macrocyclic and Supramolecular Chemistry is pleased to invite nominations for the Cram Lehn Pedersen Prize for young supramolecular chemists.

The Cram Lehn Pedersen Prize, named in honour of the winners of the 1987 Nobel Prize in Chemistry, recognises significant original and independent work in supramolecular chemistry.

Previous winners include Tom F. A. de Greef, Ivan Aprahamian, Feihe Huang, Oren Schermann, Tomoki Ogoshi, Jonathan Nitschke, and Amar Flood.

Those who are within 10 years of receiving their PhD on 31st December 2017 are eligible for the 2018 award. The winner will receive a prize of £2000 and free registration for the ISMSC meeting in Québec, Canada. In addition to giving a lecture at ISMSC, a short lecture tour will be organised after the meeting in consultation with the Editor of Chemical Communications, the sponsor of the award.

Nomination Details:

You may nominate yourself or someone else. Please send your CV, list of publications (divided into publications from your PhD and post-doc, and those from your independent work), and if desired, a letter of support, or these materials for someone you wish to nominate, to Prof. Roger Harrison (ISMSC Secretary) at rgharris@chem.byu.edu by 31st December 2017.

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Creating Defects to Enhance Oxygen Evolution Activity: A Case Study using CoFe Layered Double Hydroxides

A group of scientists recently made a breakthrough in promoting the oxygen evolution activity of metal hydroxides. They developed a simple yet efficient strategy of immersing the metal hydroxides in diluted acid solutions.

The oxygen evolution reaction (OER) is a critical component for solar-driven water splitting that can sustainably acquire a clean fuel hydrogen gas by solar energy. Certain noble metal oxides, such as iridium dioxide (IrO2) and ruthenium dioxide (RuO2), work extremely well for catalyzing OERs. However, their scarcity restricts their potential for large-scale applications. To address the cost bottleneck, inexpensive alternatives such as metal hydroxides are being investigated worldwide. Unfortunately, their performance cannot compete with IrO2 or RuO2, partly due to their limited active sites for oxygen evolution. As such, there is a current need to develop strategies to promote the oxygen evolution activity of these metal hydroxides.

Figure 1. A schematic illustration showing the structural change of CoFe layered double hydroxide after being immersed in diluted nitric acid. Acid soaking creates Fe, Co and O defects (represented by VFe, VCo, and VO in the illustration, respectively) as well as separating the hydroxide layers.

Recently, Zhou et al. from Hunan University and Shenzhen University in China, demonstrated an easy acid-etching method that is capable of significantly improving the oxygen evolution activity of CoFe layered double hydroxide. When the hydroxide comes into contact with the nitric acid, protons remove some Co, Fe and O atoms and leave behind vacancies. These vacancies are named defects (Figure 2). Oxygen gas prefers to evolve at these defects and thus the defective hydroxide exhibits improved oxygen evolution activity. In addition, the nitrate anions can intercalate in between the metal hydroxide layers and break adjacent layers apart, exposing a large number of defect-containing surfaces and thus further boosting the oxygen evolution activity (Figure 1).

Figure 2. Transmission electron microscopy images of untreated CoFe layered double hydroxide (a, b) and acid-etched CoFe layered double hydroxide (c, d). After etching, the hydroxide nanoplates crack (due to layer separation) and surfaces become rough (due to creation of defects).

This method is expected to be applicable for a wide range of other metal hydroxides. The simplicity and efficiency of this method could make oxygen evolution catalysts cost-effective for commercialization.

 

To find out more please read:

Acid-etched Layered Double Hydroxides with Rich Defects for Enhancing the Oxygen Evolution Reaction

Peng Zhou, Yanyong Wang, Chao Xie, Chen Chen, Hanwen Liu, Ru Chen, Jia Huo and Shuangyin Wang

Chem. Commun. 2017, 53, 11778-11781

About the blogger:

Tianyu Liu obtained his Ph.D. 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 an online blog writer for Chem. Commun. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

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Negative press is not always a bad thing: a novel anode material for sodium-ion batteries

At a product launch in California last week Elon Musk introduced Tesla’s new electric semi-trailer truck. Musk sells a tantalising future: one where an electric fleet replaces vehicles which currently rely on fossil fuels. Central to this fleet are powerful rechargeable batteries. Lithium-ion batteries are favoured for many current applications, such as portable electronic devices and the current offerings of full and hybrid vehicles. In coming years they are projected to be the technology of choice for the large-scale applications mentioned above and for storing power generated from intermittent renewable energy sources.

A limiting factor in the widespread roll-out of lithium batteries is that lithium is an expensive resource with low natural abundance. Sodium offers a possible alternative and has the obvious benefits of being both very cheap, and one of the most abundant elements in the earth’s crust. The electrode materials used in lithium batteries cannot be used to make the sodium variant because the sodium ion is larger (1.02 Å compared to 0.76 Å for lithium) and damages the crystalline materials optimised for lithium.

Researchers Gu, Gu and Yang at Beihang University in Beijing have reported the synthesis and performance of a novel anode material optimised for sodium. The material is a graphene-tetrahydroxybenzoquinone (Na4C6O6) hybrid, and is comprised of a porous graphene-oxide scaffold decorated with nanocrystals of Na4C6O6. Furthermore, X-ray photoelectron spectroscopy (XPS) reveals the homogenous distribution of sodium throughout this conducting material.

The electrochemical performance contrasts with previously reported materials of this type by exhibiting high cyclic stability. The reversible capacity of graphene-Na4C6O6 at a current density of 74.4 mA g-1 is 268 mA h g-1, a value which is steady over 60 cycles. This is competitive with the graphite anode materials found in lithium batteries, which have specific capacities between 200 and 400 mA h g-1. Furthermore the material performs well over a range of current densities, with reversible capacities of 95 – 211 mA h g-1 measured over a range of 3720 – 186 mA g-1.

With this work the authors contribute, at most, a viable candidate for the next rechargeable sodium battery and, at the very least, continued research into sustainable technologies. This ensures that in addressing our current energy challenges we are solving the problem, not delaying it.

To find out more please read:

3D organic Na4C6O6/graphene architecture for fast sodium storage with ultralong cycle life
Jianan Gu, Yue Gua and Shubin Yang
Chem. Commun., 2017, Advance Article
DOI: 10.1039/C7CC08045J, Communication

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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MOF catalysts show great promise for the future of industrial oxidation

Metal organic frameworks (MOFs) have enjoyed a short but illustrious career to date. Much attention has focussed on their potential for gas storage, but as the field matures an emerging function of these materials is being developed to great success: MOFs as heterogeneous catalysts.

MOFs are highly porous coordination polymers comprised of metallic ‘nodes’ connected in a 3-dimensional lattice by organic ‘linkers’. This structure offers advantages of both homogeneous and heterogeneous catalysis: their large surface area and porosity offers an accessible network of active sites, they can be recovered and recycled, and they are well-characterised and crystalline with a uniformity which facilitates reproducibility, selectivity, and systematic modification.

The authors of the review entitled ‘Tunable nature of metal organic frameworks as heterogeneous solid catalysts for alcohol oxidation’ are tasked with reviewing the literature exploring catalytic MOFs developed to selectively oxidise alcohols to aldehydes and ketones, a reaction with particular relevance to the fine chemical and pharmaceutical industries.

The review divides MOF oxidation catalysts into four categories. The first are defined by having transition-metal complexes attached to the linker, with the nodes having little to no catalytic activity. They compare to the second category, which are constructed with catalytically active metal nodes. The third category comprises photocatalysts, assembled from linkers that facilitate electron transfer to the nodes upon light irradiation, while the fourth category describes MOFs containing stabilised metallic nanoparticles.

This review highlights the most promising catalysts in each category, and MOFs are evaluated on more than catalytic performance alone. Catalysts are examined which contain precious transition metals such as ruthenium and iridium, used under reaction conditions requiring stoichiometric oxidant, base and/or co-catalyst. These are succeeded by MOFs which closely approach the ideal for industry and sustainability: a catalyst with high catalytic activity constructed from earth abundant metals such as copper and iron, which requires no added base or co-catalyst, uses air as the terminal oxidant and can be used under solvent-free conditions. And although we’re not there yet, the challenge has been set.

To find out more please read:

Tuneable nature of metal organic frameworks as heterogeneous solid catalysts for alcohol oxidation
Amarajothi Dhakshinamoorthy, Abdullah M. Asirib and Hermenegildo Garcia
Chem. Commun., 2017,53, 10851-10869
DOI10.1039/C7CC05927B

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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HOT ChemComm articles for October

All of the referee-recommended articles below are free to access until 13th December 2017.

Boron–nitrogen main chain analogues of polystyrene: poly(B-aryl)aminoboranes via catalytic dehydrocoupling
Diego A. Resendiz-Lara, Naomi E. Stubbs, Marius I. Arz, Natalie E. Pridmore, Hazel A. Sparkes and Ian Manners
Chem. Commun., 2017,53, 11701-11704
DOI: 10.1039/C7CC07331C, Communication

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Photosensitised regioselective [2+2]-cycloaddition of cinnamates and related alkenes
Santosh K. Pagire, Asik Hossain, Lukas Traub, Sabine Kerresa and Oliver Reiser
Chem. Commun., 2017,53, 12072-12075
DOI: 10.1039/C7CC06710K, Communication

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Acid-etched Layered Double Hydroxides with Rich Defects for Enhancing the Oxygen Evolution Reaction
Peng Zhou, Yanyong Wang, Chao Xie, Chen Chen, Hanwen Liu, Ru Chen, Jia Huo and Shuangyin Wang
Chem. Commun., 2017,53, 11778-11781
DOI: 10.1039/C7CC07186H, Communication

____________________________________________________

Selenoureas for anion binding as molecular logic gates
Arianna Casula, Paloma Begines, Alexandre Bettoschi, Josè G. Fernandez-Bolaños, Francesco Isaia, Vito Lippolis, Óscar López, Giacomo Picci, M. Andrea Scorciapino and Claudia Caltagirone
Chem. Commun., 2017,53, 11869-11872
DOI: 10.1039/C7CC07148E, Communcation

This article is part of the themed collection: Chemosensors and Molecular Logic

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Neutron spectroscopy as a tool in catalytic science
Alexander J. O’Malley, Stewart F. Parker and C. Richard A. Catlow
Chem. Commun., 2017,53, 12164-12176
DOI: 10.1039/C7CC05982E, Feature Article

This article is part of the themed collection: Commemorating Michael Faraday (1791-1867)

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D-Serine enzymatic metabolism induced formation of a powder-remoldable PAAM–CS hydrogel
Shuang Zhang, Qingcong Wei, Yinghui Shang, Qi Zhang and Qigang Wang
Chem. Commun., 2017, Advance Article
DOI: 10.1039/C7CC06733J, Communication

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Inorganic polystyrene gives old material a new backbone

Synthetic organic polymers and plastics revolutionised the 20th century and helped shape modern-day society. But a new range of materials with useful properties could be in the pipeline thanks to a catalytic method for making ‘inorganic polystyrene’.

Source: Royal Society of Chemistry
B-arylated polyaminoboranes prepared via catalytic dehydropolymerisation

Polystyrene is an important material in today’s society with its uses ranging from a protective packaging material through to disposable cutlery. Its chemical structure, like the majority of other important synthetic polymeric materials, has a backbone of carbon atoms. To discover new materials with useful properties, researchers have tried to replicate these structures using inorganic chains, with silicone materials being a recent example. Now, Ian Manners and his team from the University of Bristol, UK, have made inorganic polymers out of boron and nitrogen.

Read the full story by Jeremy Allen on Chemistry World.

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Desalinating Seawater with Carbon “Sandwiches”

A joint group of scientists from China, Japan and Australia recently made a breakthrough in water desalination. They designed and synthesized a multilayered electrode consisting of a graphene nanosheet sandwiched between two porous carbon particle layers. This “sandwich” electrode can be used for capacitive desalination to produce fresh water from seawater, and exhibited the highest desalination capacity among the reported graphene sheet-based electrodes.

Capacitive desalination is an emerging water desalination technique. It removes water-soluble salts, mostly sodium chloride, by applying an electric field to move the salts to the surface of electrodes. Because the amount of ions being removed is directly proportional to the surface area of the electrodes, using electrodes with abundant surface to electro-adsorb ions is critical for excellent desalination performance.

The researchers utilized graphene oxide (GO) and zeolitic imidazolate framework-8 (ZIF-8, a metal organic framework) as the two components (Figure 1a). When dissolved in water, ZIF-8 nanocrystals became attached to the surface of GO and completely covered both sides of the GO nanosheets. This process was driven by the coordination interaction between the two species. The formed ZIF-8/GO/ZIF-8 “sandwiches” were then annealed at near 1000 oC in nitrogen gas. The annealing step converted GO nanosheets and ZIF-8 nanocrystals into graphene nanosheets and porous carbon particle layers, respectively. Owing to the presence of pores on the surface of the yielded carbon particles, the carbon “sandwiches” had a high surface area of 1360 m2/g, much higher than that of the graphene sheets alone (150 m2/g).

Figure 1. (a) A schematic diagram displaying the key steps for the synthesis of the carbon “sandwiched” electrodes. 2-MeIM = 2-methylimidazole, a building block for ZIF-8. (b) The change of NaCl concentration collected for a “sandwiched” electrode (NC/rGO) and a graphene sheet electrode (rGO). When an electric field is applied, the concentration of NaCl starts to drop and reaches a plateau; When the electric field dissipates, the concentration of NaCl returns to its initial level. The salt concentration decreased to a much lower level with NC/rGO (red curve) than rGO (black curve).

The desalination capacity of the carbon “sandwich” reaches 17.52 mg/g, meaning 1 gram of the electrode can remove 17.52 mg of sodium chloride. Consistent with the enhanced surface area, the capacity of the “sandwich” is much higher than that of the graphene alone (Figure 1b). More significantly, the “sandwich” electrode outperforms all other previously reported graphene sheet-based electrodes in terms of the desalination capacity.

This work has greatly advanced the development of capacitive desalination, a promising and affordable technique to mass produce fresh water by desalting seawater.

To find out more please read:

High Performance Capacitive Deionization Electrodes Based on Ultrathin Nitrogen-doped Carbon/graphene Nano-Sandwiches

Miao Wang, Xingtao Xu, Jing Tang, Shujin Hou, Md. Shahriar A. Hossain, Likun Pan and Yusuke Yamauchi

Chem. Commun. 2017, 53, 10784-10787

About the blogger:

Tianyu Liu is a Ph.D. in chemistry graduated from University of California, Santa Cruz in United States. He is passionate about scientific communication to introduce cutting-edge researches to both the general public and the scientists with diverse research expertise. He is a web blogger for the Chem. Commun. and Chem. Sci. blog websites. More information about him can be found at http://liutianyuresearch.weebly.com/.

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