An Exceptionally Fast Homogeneous Carbon-Free Cobalt-Based Water Oxidation Catalyst

详细信息    查看全文

• 作者：Hongjin Lv ; Jie Song ; Yurii V. Geletii ; James W. Vickers ; Jordan M. Sumliner ; Djamaladdin G. Musaev ; Paul K枚gerler ; Petro F. Zhuk ; John Bacsa ; Guibo Zhu ; Craig L. Hill
• 刊名：Journal of the American Chemical Society
• 出版年：2014
• 出版时间：July 2, 2014
• 年：2014
• 卷：136
• 期：26
• 页码：9268-9271
• 全文大小：248K
• ISSN：1520-5126

文摘

An all-inorganic, oxidatively and thermally stable, homogeneous water oxidation catalyst based on redox-active (vanadate(V)-centered) polyoxometalate ligands, Na₁₀[Co₄(H₂O)₂(VW₉O₃₄)₂]路35H₂O (Na₁₀1-V2, sodium salt of the polyanion 1-V2), was synthesized, thoroughly characterized and shown to catalyze water oxidation in dark and visible-light-driven conditions. This synthetic catalyst is exceptionally fast under mild conditions (TOF > 1 脳 10³ s^鈥?). Under light-driven conditions using [Ru(bpy)₃]²⁺ as a photosensitizer and persulfate as a sacrificial electron acceptor, 1-V2 exhibits higher selectivity for water oxidation versus bpy ligand oxidation, the final O₂ yield by 1-V2 is twice as high as that of using [Co₄(H₂O)₂(PW₉O₃₄)₂]^{10鈥?/sup> (1-P2), and the quantum efficiency of O₂ formation at 6.0 渭M 1-V2 reaches 68%. Multiple experimental results (e.g., UV鈥搗is absorption, FT-IR, 51V NMR, dynamic light scattering, tetra-n-heptylammonium nitrate-toluene extraction, effect of pH, buffer, and buffer concentration, etc.) confirm that the polyanion unit (1-V2) itself is the dominant active catalyst and not Co2+(aq) or cobalt oxide.}