Sunset for perovskites?

Hugh Cowley writes about a hot Chemical Science article for Chemistry World

Perovskites have arguably transformed solar energy more in the last few years than other technologies have in decades. But British researchers have called into question optimistic predictions of undiscovered perovskites.

© Shutterstock

Hybrid perovskites are a mix of organic and inorganic ions with the same crystal structure as calcium titanium oxide (CaTiO3). Halide perovskites are a subset of these structures containing halide ions such as fluoride or chloride. Iodide perovskites such as methylammonium lead iodide (CH3NH3PbI3) can convert sunlight to electricity.

Researchers use a decades-old geometric ‘tolerance factor’ to propose new combinations of ions that will form stable perovskites. Now, Robert Palgrave and his team at University College London, UK, have reassessed the validity of the tolerance factor in predicting new hybrid perovskite structures. Read the full article in Chemistry World»


Read the original journal article in Chemical Science – it’s open access:
On the application of the tolerance factor to inorganic and hybrid halide perovskites: a revised system
W. Travis, E. N. K. Glover, H. Bronstein, D. O. Scanlon and R. G. Palgrave 
Chem. Sci., 2016, Advance Article, DOI: 10.1039/C5SC04845A, Edge Article

 
Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Iron-rich silicate plays cosmic matchmaker

Nelly Berg writes about a hot ChemComm article for Chemistry World

Computational chemists in Spain have discovered that iron in cosmic dust grains helps turn hydrogen atoms into molecular hydrogen (H2).

The average density of the interstellar medium is several billion times less dense than even the best vacuum chambers on Earth. Collisions between hydrogen atoms are therefore rare, and when they do occur, only one out of every 100,000 creates H2. Read the full article in Chemistry World»


Read the original journal article in ChemComm – it’s open access:
Does Fe2+ in olivine-based interstellar grains play any role in the formation of H2? Atomistic insights from DFT periodic simulations
J. Navarro-Ruiz, P. Ugliengo, M. Sodupe and A. Rimola 
Chem. Commun., 2016, Advance Article, DOI: 10.1039/C6CC02313D, Communication

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Caging chemical weapons

Elisabeth Ratcliffe writes about a hot ChemComm article for Chemistry World

Scientists in the UK have developed supramolecular cages that can trap chemical weapon simulants using the hydrophobic effect.

Organophosphorous chemical weapons, such as sarin and soman, interfere with signals between nerve cells, and have recently been used to deadly effect in places such as Syria. Researchers are therefore trying to develop techniques that detect these chemical weapons in the environment, and destroy them. Read the full article in Chemistry World»


Read the original journal article in ChemComm – it’s open access:
Binding of chemical warfare agent simulants as guests in a coordination cage: contributions to binding and a fluorescence-based response
Christopher G. P. Taylor, Jerico R. Piper and Michael D. Ward 
DOI: 10.1039/C6CC02021F, Communication

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Macrocyle aromaticity switch is all about that base

Heather Powell writes about a hot ChemComm article for Chemistry World

Researchers have discovered a macrocyle that they can render aromatic, non-aromatic or anti-aromatic by altering the amount of base they add.

 

Meso-aryl expanded porphyrins are usually exceedingly twisted structures due to strong hydrogen bonds within them. Even though they contain many conjugated bonds, this twisted structure means that most of these porphyrins are non-aromatic (to be aromatic, a molecule not only needs conjugation, but must also be flat). Previously scientists had added hydrogen ions to disturb hydrogen bonding in porphyrins, causing them to untwist and become aromatic. Here, a team led by Dongho Kim from Yonsei University, Korea, have flattened a porphyrin by removing hydrogen ions. Read the full article in Chemistry World»


Read the original research in ChemComm – it’s free to read until 20 May 2016:
Multifaceted [36]octaphyrin(1.1.1.1.1.1.1.1): deprotonation-induced switching among nonaromatic, Möbius aromatic, and Hückel antiaromatic species
Won-Young Cha, Takanori Soya, Takayuki Tanaka, Hirotaka Mori, Yongseok Hong, Sangsu Lee, Kyu Hyung Park, Atsuhiro Osuka and Dongho Kim 
DOI: 10.1039/C6CC02051H, Communication

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

‘Lightning talk’ prize winner at the University of California Symposium for Chemical Sciences

Congratulations to our ChemComm ‘lightning talk’ prize winner at the University of California Symposium for the Chemical Sciences.
Liban Saleh from the Spokoyny group

The meeting was supported by eight UC departments (UC Davis, UCLA, UC San Diego, UC Berkeley, UC Riverside, UC Santa Cruz, UC Irvine, UC Santa Barbara) representing all areas of chemistry including biological, organic, inorganic, analytical and physical chemistry. The symposium which was held for the first time provided an excellent opportunity for graduate students and postdocs to not only present their work in a multidisciplinary environment, but also take part in different workshops to further their career and establish connections with professionals from industry, government and alternative science jobs.

We would like to congratulate the winner of the best ‘lightning talk’, a short representation of the speaker’s research of about 5 min.  The prize was given to Liban Saleh who is currenlty working as a Post-Doctoral Associate in the group of Alexander Spokoyny (UCLA). His research focuses on inorganic and organomimetic cluster chemistry towards functional materials.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Fluorescently finding a specific disease marker needle in a biological haystack

In a recent ChemComm Feature Article, researchers from the University of Bath review and highlight advances in the combination of carbohydrates and boronic acids to detect fluorescently disease markers. Anthea Blackburn explains further…

The early detection and monitoring of disease is a somewhat recent advancement in healthcare that offers the significant advantage of being able to treat an illness in its initial stages, rather than once it has already manifested itself in the patient. Such a feat requires, however, the ability to see very specific and characteristic disease markers in situ, not unlike the search for a needle in a haystack.
 
Luckily, with the advent of fluorescence (and other) imaging techniques, methods have been developed whereby, in combination with contrast agents that are able to interact with specific molecules in the body, cell chemistry and function can be observed with high sensitivity, and, more importantly, abnormalities in these processes noticed in real time.
 
The art and ultimate success of this fluorescence imaging comes from the design of the contrast agent employed – the probe should be able to selectively recognise and target the relevant disease marker reversibly and under biological conditions. A number of approaches currently exist that meet these requirements, one of which is the boronic acid recognition motif that is able to act as a molecular receptor for the 1,2- and 1,3-diols commonly expressed in carbohydrates and complex glycoproteins. Tony James and his team from the University of Bath, whose own research focuses on such use of boronic acid receptors in the detection of carbohydrates, have summarised the recent and exciting advances in this particular field of selective biological imaging.
 
The well-known and strong affinity of boronic acids for carbohydrates offers a convenient means of detecting commonly expressed markers in diseases including some cancers, as well as Alzheimer’s, autoimmune, and heart diseases. As such, the attachment of this relatively simple chemical moiety to fluorescent small molecular, polymeric or benzoxaborale-based probes offers a diagnostic tool that is able to detect, monitor, and aid in the personalised treatment of such significant and life-changing diseases.
 
This Feature Article convincingly highlights the impact that boronic acid-based fluorescence imaging will ultimately have on a range of important clinical and theranostic practices and their successes.
  
Read this hot ChemComm article in full:
X. Sun, W. Zhai, J. S. Fossey and T. D. James
Chem. Commun., 2016, 52, 3456–3469
DOI: 10.1039/C5CC08633G

About the Writer:
Anthea Blackburn is a guest Web Writer for Chemical Communications. Anthea hails from New Zealand, carried out her graduate studies in mechanostereochemistry under the guidance of Prof. Fraser Stoddart in the US, and has recently relocated to live in London. She is a recent addition to the Econic Technologies team, where she is working on the development of new catalysts for the environmentally beneficial preparation of polycarbonates from CO2.
Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Hot ChemComm articles for March

Take a look at this selection of recently published referee-recommended articles – all are free to read* until 17 April.

Printed microelectrodes for scalable, high-areal-capacity lithium–sulfur batteries
Craig Milroy and Arumugam Manthiram
DOI: 10.1039/C5CC10503J, Communication

C5CC10503J GA


Lanthanide-based luminescence biolabelling
Mohamadou Sy, Aline Nonat, Niko Hildebrandt and Loïc J. Charbonnière
DOI: 10.1039/C6CC00922K, Feature Article

C6CC00922K GA


Superior anti-CO poisoning capability: Au-decorated PtFe nanocatalysts for high-performance methanol oxidation
Zhao Cai, Zhiyi Lu, Yongmin Bi, Yaping Li, Yun Kuang and Xiaoming Sun
DOI: 10.1039/C5CC10513G, Communication

C5CC10513G GA


Pharmaceutical nanocrystals confined in porous host systems – interfacial effects and amorphous interphases
N. Sonnenberger, N. Anders, Y. Golitsyn, M. Steinhart, D. Enke, K. Saalwächter and M. Beiner
DOI: 10.1039/C6CC00962J, Communication
From themed collection Pharmaceutical Solids

C6CC00962J GA


Rupture force of cell adhesion ligand tethers modulates biological activities of a cell-laden hydrogel
Min Kyung Lee, Jooyeon Park, Xuefeng Wang, Mehdi Roein-Peikar, Eunkyung Ko, Ellen Qin, Jonghwi Lee, Taekjip Ha and Hyunjoon Kong
DOI: 10.1039/C6CC00036C, Communication

C6CC00036C GA


High-symmetry hydrogen-bonded organic frameworks: air separation and crystal-to-crystal structural transformation
Dong-Dong Zhou, Yan-Tong Xu, Rui-Biao Lin, Zong-Wen Mo, Wei-Xiong Zhang and Jie-Peng Zhang
DOI: 10.1039/C6CC00366D, Communication

C6CC00366D GA

*Access is free through a registered RSC account

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Hypervalent iodine reagent’s aversion to conversion

Richard Massey writes about a hot ChemComm article for Chemistry World

Computational studies have unpicked the surprising stability behind high-energy fluorinating reagent Togni reagent I.

Togni reagents – named after creator Antonio Togni – are trifluoromethylating agents that introduce the CF3 group often found in pharmaceuticals and agrochemicals. They’re members of a family of benziodoxole-based hypervalent iodine reagents that transfer atoms or functional groups loaded onto their oxygen and hypervalent iodine-containing five-membered ring. Read the full article in Chemistry World» 

 


 

Read the original journal article in ChemComm – it’s free to access until 21 April 2016:
Why does Togni’s reagent I exist in the high-energy hypervalent iodine form? Re-evaluation of benziodoxole based hypervalent iodine reagents
Tian-Yu Sun, Xiao Wang, Hao Geng, Yaoming Xie, Yun-Dong Wu, Xinhao Zhang and Henry F. Schaefer III 
DOI: 10.1039/C6CC00384B, Communication

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Enzyme mutagenesis sweetens prebiotics

Eleanor Hall writes about a hot ChemComm article for Chemistry World

Sugar lumpsEuropean scientists have developed an enzyme to cleanly and cheaply produce a healthier sugar with prebiotic properties.

Prebiotics – compounds that nourish the good bacteria in our gut – have become important synthetic targets due to their potential role in preventing diseases such as obesity and type 2 diabetes. There are a limited number currently available for use in food, and most do not have the additional benefit of tasting sweet. Read the full article in Chemistry World»


Read the original journal article in ChemComm – it’s free to access until 30 March 2016:
Converting bulk sugars into prebiotics: semi-rational design of a transglucosylase with controlled selectivity
Tom Verhaeghe, Karel De Winter, Magali Berland, Rob De Vreese, Matthias D’hooghe, Bernard Offmann and Tom Desmet 
Chem. Commun., 2016, DOI: 10.1039/C5CC09940D, Communication

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Solar cells firing on all cylinders

William Bergius writes about a hot ChemComm article for Chemistry World

Scientists in china have manufactured cylindrical dye-sensitised solar cells (DSSCs) capable of generating a stable electrical output at different times of the day. Compared to their traditional flat counterparts, if correctly positioned so that the sun moves around their axis, their output is far less dependent of the angle of the sun. Read the full article in Chemistry World»


Read the original journal article in ChemComm – it’s free to read* until 22nd March 2016:
Cylindrical dye-sensitized solar cells with high efficiency and stability over time and incident angle
Qunwei Tang, Lei Zhang, Benlin He, Liangmin Yu and Peizhi Yang 
DOI: 10.1039/C5CC10105K, Communication

*Access is free through a registered RSC account

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)