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14 Sep 00:00

A porous proton-relaying metal-organic framework material that accelerates electrochemical hydrogen evolution

by Idan Hod


Hydrogen evolution technologies for a future carbon-free energy economy require efficient catalysts which can be implemented on a large scale. Here, the authors prepare a composite electrode from readily available elements, whereby a metal-organic framework boosts catalytic performance by enabling rapid proton transport.

Nature Communications doi: 10.1038/ncomms9304

Authors: Idan Hod, Pravas Deria, Wojciech Bury, Joseph E. Mondloch, Chung-Wei Kung, Monica So, Matthew D. Sampson, Aaron W. Peters, Cliff P. Kubiak, Omar K. Farha, Joseph T. Hupp

15 Sep 00:00

Efficient direct solar-to-hydrogen conversion by in situ interface transformation of a tandem structure

by Matthias M. May


A future carbon-free energy economy requires an efficient photocatalytic route to hydrogen generation. Here, the authors employ surface modification techniques to raise the performance of an unassisted solar water splitting device to achieve exceptional performances.

Nature Communications doi: 10.1038/ncomms9286

Authors: Matthias M. May, Hans-Joachim Lewerenz, David Lackner, Frank Dimroth, Thomas Hannappel

19 Aug 17:31

Highly Robust Hydrogen Generation by Bioinspired Ir Complexes for Dehydrogenation of Formic Acid in Water: Experimental and Theoretical Mechanistic Investigations at Different pH

by Wan-Hui Wang, Mehmed Z. Ertem, Shaoan Xu, Naoya Onishi, Yuichi Manaka, Yuki Suna, Hide Kambayashi, James T. Muckerman, Etsuko Fujita and Yuichiro Himeda

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ACS Catalysis
DOI: 10.1021/acscatal.5b01090
13 Aug 14:20

Earth-abundant metal complexes as catalysts for water oxidation; is it homogeneous or heterogeneous?

Catal. Sci. Technol., 2015, Advance Article
DOI: 10.1039/C5CY01251A, Minireview
Md. Ali Asraf, Hussein A. Younus, Mekhman Yusubov, Francis Verpoort
This minireview focuses on the aspects that determine whether particular catalysts for the oxidation of water are homogeneous or heterogeneous.
To cite this article before page numbers are assigned, use the DOI form of citation above.
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05 Aug 12:08

Morphology and Active-Site Engineering for Stable Round-Trip Efficiency Li–O2 Batteries: A Search for the Most Active Catalytic Site in Co3O4

by Kyeongse Song, Eunbi Cho and Yong-Mook Kang

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ACS Catalysis
DOI: 10.1021/acscatal.5b01196
05 Aug 17:09

Reactivity and Mechanism Studies of Hydrogen Evolution Catalyzed by Copper Corroles

by Haitao Lei, Huayi Fang, Yongzhen Han, Wenzhen Lai, Xuefeng Fu and Rui Cao

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ACS Catalysis
DOI: 10.1021/acscatal.5b00666
10 Aug 19:16

A Molecular Copper Catalyst for Hydrogenation of CO2 to Formate

by Christopher M. Zall, John C. Linehan and Aaron M. Appel

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ACS Catalysis
DOI: 10.1021/acscatal.5b01646
10 Aug 19:16

α-Fe2O3/NiOOH: An Effective Heterostructure for Photoelectrochemical Water Oxidation

by Francesco Malara, Alessandro Minguzzi, Marcello Marelli, Sara Morandi, Rinaldo Psaro, Vladimiro Dal Santo and Alberto Naldoni

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ACS Catalysis
DOI: 10.1021/acscatal.5b01045
30 Jul 00:00

Active Sites for Light Driven Proton Reduction in Y 2 Ti 2 O 7 and CsTaWO 6 Pyrochlore Catalysts Detected by In Situ EPR


In situ EPR spectroscopy proved to be a versatile tool to identify active sites for photocatalytic hydrogen generation in modified Y2Ti2O7 and CsTaWO6 catalysts of pyrochlore structure, in which the metal cations are located in two different positions A and B. It was found that the B-sites exclusively occupied by titanium (Y2Ti2O7) and tantalum/tungsten (CsTaWO6) act as electron traps on the surface. From these sites, electron transfer to the co-catalysts proceeds. Thus, the B-sites are responsible for photocatalytic water reduction.

Graphical Abstract

04 Aug 00:00

EPR Spectroscopy as a Tool in Homogeneous Catalysis Research


In the context of homogeneous catalysis, open-shell systems are often quite challenging to characterize. Nuclear magnetic resonance (NMR) spectroscopy is the most frequently applied tool to characterize organometallic compounds, but NMR spectra are usually broad, difficult to interpret and often futile for the study of paramagnetic compounds. As such, electron paramagnetic resonance (EPR) has proven itself as a useful spectroscopic technique to characterize paramagnetic complexes and reactive intermediates. EPR spectroscopy is a particularly useful tool to investigate their electronic structures, which is fundamental to understand their reactivity. This paper describes some selected examples of studies where EPR spectroscopy has been useful for the characterization of open-shell organometallic complexes. The paper concentrates in particular on systems where EPR spectroscopy has proven useful to understand catalytic reaction mechanisms involving paramagnetic organometallic catalysts. The expediency of EPR spectroscopy in the study of organometallic chemistry and homogenous catalysis is contextualized in the introductory Sect. 1. Section 2 of the review focusses on examples of C–C and C–N bond formation reactions, with an emphasis on catalytic reactions where ligand/substrate non-innocence plays an important role. Both carbon and nitrogen centered radicals have been shown to play an important role in these reactions. A few selected examples of catalytic alcohol oxidation proceeding via related N-centered ligand radicals are included in this section as well. Section 3 covers examples of the use of EPR spectroscopy to study important commercial ethylene oligomerization and polymerization processes. In Sect. 4 the use of EPR spectroscopy to understand the mechanisms of Atom Transfer Radical Polymerization is discussed. While this review focusses predominantly on the application of EPR spectroscopy in mechanistic studies of C–C and C–N bond formation reactions mediated by organometallic catalysts, a few selected examples describing the application of EPR spectroscopy in other catalytic reactions such as water splitting, photo-catalysis, photo-redox-catalysis and related reactions in which metal initiated (free) radical formation plays a role are included as well. EPR spectroscopic investigation in this area of research are dominated by EPR spectroscopic studies in isotropic solution, including spin trapping experiments. These reactions are highlighted in Sect. 5. EPR spectroscopic studies have proven useful to discern the correct oxidation states of the active catalysts and also to determine the effective concentrations of the active species. EPR is definitely a spectroscopic technique that is indispensable in understanding the reactivity of paramagnetic complexes and in conjunction with other advanced techniques such as X-ray absorption spectroscopy and pulsed laser polymerization it will continue to be a very practical tool.

22 Jul 17:17

Water oxidation catalysed by iron complex of N,N[prime or minute]-dimethyl-2,11-diaza[3,3](2,6)pyridinophane. Spectroscopy of iron-oxo intermediates and density functional theory calculations

Chem. Sci., 2015, 6,5891-5903
DOI: 10.1039/C5SC01680K, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Wai-Pong To, Toby Wai-Shan Chow, Chun-Wai Tse, Xiangguo Guan, Jie-Sheng Huang, Chi-Ming Che
FeIV=O and/or FeV=O intermediates are suggested to be involved in water oxidation with [NH4]2[CeIV(NO3)6], NaIO4, or Oxone catalyzed by [FeIII(L1)Cl2]+ (1) on the basis of spectroscopic measurements and DFT calculations.
The content of this RSS Feed (c) The Royal Society of Chemistry
20 Jul 14:34

Gold-Coated Cobalt Ferrite Nanoparticles via Methionine-Induced Reduction

by Agnė Mikalauskaitė, Rokas Kondrotas, Gediminas Niaura and Aru̅nas Jagminas

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The Journal of Physical Chemistry C
DOI: 10.1021/acs.jpcc.5b03528
21 Jul 19:20

Rechargeable Hydrogen Storage System Based on the Dehydrogenative Coupling of Ethylenediamine with Ethanol

by Peng Hu, Yehoshoa Ben-David, David Milstein


A novel and simple hydrogen storage system was developed, based on the dehydrogenative coupling of inexpensive ethylenediamine with ethanol to form diacetylethylenediamine. The system is rechargeable and utilizes the same ruthenium pincer catalyst for both hydrogen loading and unloading procedures. It is efficient and uses a low catalyst loading. Repetitive reversal reactions without addition of new catalyst result in excellent conversions in both the dehydrogenation and hydrogenation procedures in three cycles.

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In support of the hydrogen economy: An efficient and simple homogeneous hydrogen carrier system was developed based on the dehydrogenative coupling of ethylenediamine with ethanol to form diacetylethylenediamine. The same ruthenium pincer catalyst is used for both hydrogen loading and unloading reactions.

17 Jul 14:46

In Situ-Generated Co0-Co3O4/N-Doped Carbon Nanotubes Hybrids as Efficient and Chemoselective Catalysts for Hydrogenation of Nitroarenes

by Zhongzhe Wei, Jing Wang, Shanjun Mao, Diefeng Su, Haiyan Jin, Yihe Wang, Fan Xu, Haoran Li and Yong Wang

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ACS Catalysis
DOI: 10.1021/acscatal.5b00737
13 Jul 20:09

Organic Dye-Sensitized Tandem Photoelectrochemical Cell for Light Driven Total Water Splitting

by Fusheng Li, Ke Fan, Bo Xu, Erik Gabrielsson, Quentin Daniel, Lin Li and Licheng Sun

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Journal of the American Chemical Society
DOI: 10.1021/jacs.5b04856
16 Jul 00:00

A generic concept to overcome bandgap limitations for designing highly efficient multi-junction photovoltaic cells

by Fei Guo


The efficiency of a single-junction photovoltaic cell is constrained by the Shockley-Queisser limit. Here, the authors adopt a triple-junction configuration which relaxes material and current-matching constraints, providing a generic strategy for advancing the efficiency roadmap of photovoltaic technologies.

Nature Communications doi: 10.1038/ncomms8730

Authors: Fei Guo, Ning Li, Frank W. Fecher, Nicola Gasparini, Cesar Omar Ramirez Quiroz, Carina Bronnbauer, Yi Hou, Vuk V. Radmilović, Velimir R. Radmilović, Erdmann Spiecker, Karen Forberich, Christoph J. Brabec

15 Jul 00:00

Why we are teaching science wrong, and how to make it right

by M. Mitchell Waldrop

Why we are teaching science wrong, and how to make it right

Nature 523, 7560 (2015).

Author: M. Mitchell Waldrop

Active problem-solving confers a deeper understanding of science than does a standard lecture. But some university lecturers are reluctant to change tack.

15 Jul 00:00

Lifelong learning: Science professors need leadership training

by Charles E. Leiserson

Lifelong learning: Science professors need leadership training

Nature 523, 7560 (2015). doi:10.1038/523279a

Authors: Charles E. Leiserson & Chuck McVinney

To drive discovery, scientists heading up research teams large and small need to learn how people operate, argue Charles E. Leiserson and Chuck McVinney.

10 Jul 08:28

Catalyst characterisation techniques and reaction cells operating at realistic conditions; towards acquisition of kinetically relevant information

Catal. Sci. Technol., 2015, Advance Article
DOI: 10.1039/C5CY00269A, Perspective
Nikolaos E. Tsakoumis, Andrew P. E. York, De Chen, Magnus Ronning
Catalyst characterisation techniques and reaction cells operating at realistic conditions; towards acquisition of kinetically relevant information.
To cite this article before page numbers are assigned, use the DOI form of citation above.
The content of this RSS Feed (c) The Royal Society of Chemistry
16 Jul 12:39

Perovskite Solar Cells with Near 100% Internal Quantum Efficiency Based on Large Single Crystalline Grains and Vertical Bulk Heterojunctions

by Bin Yang, Ondrej Dyck, Jonathan Poplawsky, Jong Keum, Alexander Puretzky, Sanjib Das, Ilia Ivanov, Christopher Rouleau, Gerd Duscher, David Geohegan and Kai Xiao

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Journal of the American Chemical Society
DOI: 10.1021/jacs.5b03144
01 Jun 13:31

Stable Cobalt Nanoparticles and Their Monolayer Array as an Efficient Electrocatalyst for Oxygen Evolution Reaction

by Liheng Wu, Qing Li, Cheng Hao Wu, Huiyuan Zhu, Adriana Mendoza-Garcia, Bo Shen, Jinghua Guo and Shouheng Sun

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Journal of the American Chemical Society
DOI: 10.1021/jacs.5b04142
12 Jun 15:55

Simple and Efficient System for Combined Solar Energy Harvesting and Reversible Hydrogen Storage

by Lu Li, Xiaoyue Mu, Wenbo Liu, Zetian Mi and Chao-Jun Li

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Journal of the American Chemical Society
DOI: 10.1021/jacs.5b03505
10 Jun 00:00

Highly active oxygen reduction non-platinum group metal electrocatalyst without direct metal–nitrogen coordination

by Kara Strickland


The active site of many non-noble metal cathodic oxygen reduction catalysts consists of a nitrogen-corodinated transition metal. Here, the authors report an iron-based electrocatalyst devoid of iron–nitrogen coordination, and demonstrate its high activity in acid and alkaline media.

Nature Communications doi: 10.1038/ncomms8343

Authors: Kara Strickland, Elise Miner, Qingying Jia, Urszula Tylus, Nagappan Ramaswamy, Wentao Liang, Moulay-Tahar Sougrati, Frédéric Jaouen, Sanjeev Mukerjee

11 Jun 00:00

Efficient photosynthesis of carbon monoxide from CO2 using perovskite photovoltaics

by Marcel Schreier


Artificial photosynthesis is a means of harnessing solar energy to generate fuels but has traditionally been exploited for the generation of hydrogen. Here, Schreier et al . instead employ a perovskite photovoltaic device to effect the solar conversion of CO 2 to CO with high efficiency.

Nature Communications doi: 10.1038/ncomms8326

Authors: Marcel Schreier, Laura Curvat, Fabrizio Giordano, Ludmilla Steier, Antonio Abate, Shaik M. Zakeeruddin, Jingshan Luo, Matthew T. Mayer, Michael Grätzel

15 Jun 00:00

In situ oxidation of carbon-encapsulated cobalt nanocapsules creates highly active cobalt oxide catalysts for hydrocarbon combustion

by Han Wang


Palladium is an effective but expensive catalyst used in catalytic converters. Here, the authors show that defective Co 3 O 4 nanocrystals, synthesized via oxidation of carbon-encapsulated cobalt nanoparticles, display similar or even comparable catalytic activity to palladium for hydrocarbon combustion.

Nature Communications doi: 10.1038/ncomms8181

Authors: Han Wang, Chunlin Chen, Yexin Zhang, Lixia Peng, Song Ma, Teng Yang, Huaihong Guo, Zhidong Zhang, Dang Sheng Su, Jian Zhang

19 May 16:02

Rational design of self-assembly pathways [Chemistry]

by Jacobs, W. M., Reinhardt, A., Frenkel, D.
The field of complex self-assembly is moving toward the design of multiparticle structures consisting of thousands of distinct building blocks. To exploit the potential benefits of structures with such “addressable complexity,” we need to understand the factors that optimize the yield and the kinetics of self-assembly. Here we use a...
11 Jun 18:50

[Report] High-performance photovoltaic perovskite layers fabricated through intramolecular exchange

by Woon Seok Yang
The band gap of formamidinium lead iodide (FAPbI3) perovskites allows broader absorption of the solar spectrum relative to conventional methylammonium lead iodide (MAPbI3). Because the optoelectronic properties of perovskite films are closely related to film quality, deposition of dense and uniform films is crucial for fabricating high-performance perovskite solar cells (PSCs). We report an approach for depositing high-quality FAPbI3 films, involving FAPbI3 crystallization by the direct intramolecular exchange of dimethylsulfoxide (DMSO) molecules intercalated in PbI2 with formamidinium iodide. This process produces FAPbI3 films with (111)-preferred crystallographic orientation, large-grained dense microstructures, and flat surfaces without residual PbI2. Using films prepared by this technique, we fabricated FAPbI3-based PSCs with maximum power conversion efficiency greater than 20%. Authors: Woon Seok Yang, Jun Hong Noh, Nam Joong Jeon, Young Chan Kim, Seungchan Ryu, Jangwon Seo, Sang Il Seok
10 Jun 11:25

Light converting phosphor-based photocatalytic composites

Catal. Sci. Technol., 2015, 5,4727-4740
DOI: 10.1039/C5CY00622H, Minireview
Xinjuan Liu, Haipeng Chu, Jinliang Li, Lengyuan Niu, Can Li, Huili Li, Likun Pan, Chang Q. Sun
Light-conversion phosphor-based composites including up-conversion, down-conversion, and long afterglow phosphor-semiconductors for efficient photocatalysis are summarized.
The content of this RSS Feed (c) The Royal Society of Chemistry
05 May 18:52

Transient Absorption Spectroscopy of Anatase and Rutile: The Impact of Morphology and Phase on Photocatalytic Activity

by Xiuli Wang, Andreas Kafizas, Xiaoe Li, Savio J. A. Moniz, Philip J. T. Reardon, Junwang Tang, Ivan P. Parkin and James R. Durrant

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The Journal of Physical Chemistry C
DOI: 10.1021/acs.jpcc.5b01858
30 Mar 12:54

In-Depth Studies on Rapid Photochemical Activation of Various Sol–Gel Metal Oxide Films for Flexible Transparent Electronics

by Sungjun Park, Kwang-Ho Kim, Jeong-Wan Jo, Sujin Sung, Kyung-Tae Kim, Won-June Lee, Jaekyun Kim, Hyun Jae Kim, Gi-Ra Yi, Yong-Hoon Kim, Myung-Han Yoon, Sung Kyu Park

Despite intensive research on photochemical activation of sol–gel metal oxide materials, the relatively long processing time and lack of deep understanding of the underlying chemical courses have limited their broader impact on diverse materials and applications such as thin-film electronics, photovoltaics, and catalysts. Here, in-depth studies on the rapid photochemical activation of diverse sol–gel oxide films using various spectroscopic and electrical investigations for the underlying physicochemical mechanism are reported. Based on the exhaustive chemical and physical analysis, it is noted that deep ultraviolet-promoted rapid film formation such as densification, polycondensation, and impurity decomposition is possible within 5 min via in situ radical-mediated reactions. Finally, the rapid fabrication of all-solution metal oxide thin-film-transistor circuitry, which exhibits stable and reliable electrical performance with a mobility of >12 cm2 V−1 s−1 and an oscillation frequency of >650 kHz in 7-stage ring oscillator even after bending at a radius of <1 mm is demonstrated.

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The general physicochemical mechanisms underlying photoactivated sol–gel reactions are described, with comprehensive chemical and structural analysis inducing rapid (<5 min) fabrication of various metal oxide films at low temperatures (<150 °C), and all-solution processed high-performance electronic devices and circuitry on ultrathin polymeric substrates are demonstrated. This will open new possibilities to prepare future electronic materials in a fast, scalable, and economic manner.