FN Thomson Reuters Web of Scienceā„¢ VR 1.0 PT J AU Smolentsev, G Cecconi, B Guda, A Chavarot-Kerlidou, M van Bokhoven, JA Nachtegaal, M Artero, V AF Smolentsev, Grigory Cecconi, Bianca Guda, Alexander Chavarot-Kerlidou, Murielle van Bokhoven, Jeroen A. Nachtegaal, Maarten Artero, Vincent TI Microsecond X-ray Absorption Spectroscopy Identification of Co-I Intermediates in Cobaloxime-Catalyzed Hydrogen Evolution SO CHEMISTRY-A EUROPEAN JOURNAL LA English DT Article DE photocatalysis; solar fuels; transient X-ray absorption; XANES; X-ray absorption spectroscopy ID MOLECULAR-HYDROGEN; WATER; COBALT; COMPLEXES; ACTIVATION; GENERATION; MECHANISM; SYSTEMS; ENERGY; H-2 AB Rational development of efficient photocatalytic systems for hydrogen production requires understanding the catalytic mechanism and detailed information about the structure of intermediates in the catalytic cycle. We demonstrate how time-resolved X-ray absorption spectroscopy in the microsecond time range can be used to identify such intermediates and to determine their local geometric structure. This method was used to obtain the solution structure of the Co-I intermediate of cobaloxime, which is a non-noble metal catalyst for solar hydrogen production from water. Distances between cobalt and the nearest ligands including two solvent molecules and displacement of the cobalt atom out of plane formed by the planar ligands have been determined. Combining in situ X-ray absorption and UV/Vis data, we demonstrate how slight modification of the catalyst structure can lead to the formation of a catalytically inactive Co-I state under similar conditions. Possible deactivation mechanisms are discussed. C1 [Smolentsev, Grigory; van Bokhoven, Jeroen A.; Nachtegaal, Maarten] Paul Scherrer Inst, CH-5232 Villigen, Switzerland. [Cecconi, Bianca; Chavarot-Kerlidou, Murielle; Artero, Vincent] Univ Grenoble Alpes, CEA, CNRS, Lab Chem & Biol Met, Grenoble, France. [Cecconi, Bianca] Univ Milano Bicocca, Dept Mat Sci, I-20125 Milan, Italy. [Cecconi, Bianca] Univ Milano Bicocca, INSTM Unit, Milano Bicocca Solar Energy Res Ctr, I-20125 Milan, Italy. [Guda, Alexander] Southern Fed Univ, Int Res Ctr Smart Mat, Rostov Na Donu 344090, Russia. [van Bokhoven, Jeroen A.] ETH, Inst Chem & Bioengn, CH-8093 Zurich, Switzerland. RP Smolentsev, G (reprint author), Paul Scherrer Inst, CH-5232 Villigen, Switzerland. EM grigory.smolentsev@psi.ch RI Artero, Vincent/C-6853-2008; Guda, Alexander/A-3671-2015 OI Artero, Vincent/0000-0002-6148-8471; Cecconi, Bianca/0000-0002-9200-6316; Guda, Alexander/0000-0002-6941-4987 FU Swiss National Science Foundation [200021-135226]; European Commission [290605]; ERC [306398]; French National Research Agency (Labex program, ARCANE) [ANR-11-LABX-0003-01]; Russian Foundation for Basic Research [14-02-31555]; Ministry of Education and Science of Russia [RFMEFI58714X0002] FX This work was supported by the Swiss National Science Foundation (grant no. 200021-135226), European Commission's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 290605 (COFUND: PSI-FELLOW) and ERC Grant Agreement no. 306398, the French National Research Agency (Labex program, ARCANE, ANR-11-LABX-0003-01), and Russian Foundation for Basic Research (project #14-02-31555). JAvB thanks the NCCR MUST. A.G. would like to thank Ministry of Education and Science of Russia (project #RFMEFI58714X0002). The COST Action CM1202 PERSPECT-H2O is also acknowledged. NR 38 TC 1 Z9 1 U1 17 U2 17 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 0947-6539 EI 1521-3765 J9 CHEM-EUR J JI Chem.-Eur. J. PD OCT 19 PY 2015 VL 21 IS 43 BP 15158 EP 15162 DI 10.1002/chem.201502900 PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA CU2DF UT WOS:000363332200016 PM 26388205 ER EF