‡UNILAB, State Key Lab of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China.
J Am Chem Soc. 2015 Apr 1;137(12):4223-9. doi: 10.1021/jacs.5b01006. Epub 2015 Mar 19.
Oxygen evolution from water poses a significant challenge in solar fuel production because it requires an efficient catalyst to bridge the one-electron photon capture process with the four-electron oxygen evolution reaction (OER). Here, a new strategy was developed to synthesize nonsupported ultrasmall cobalt oxide nanocubanes through an in situ phase transformation mechanism using a layered Co(OH)(OCH3) precursor. Under sonication, the precursor was exfoliated and transformed into cobalt oxide nanocubanes in the presence of NaHCO3-Na2SiF6 buffer solution. The resulting cobalt catalyst with an average particle size less than 2 nm exhibited a turnover frequency of 0.023 per second per cobalt in photocatalytic water oxidation. X-ray absorption results suggested a unique nanocubane structure, where 13 cobalt atoms fully coordinated with oxygen in an octahedral arrangement to form 8 Co4O4 cubanes, which may be responsible for the exceptionally high OER activity.
从水中产生氧气在太阳能燃料生产中是一个重大的挑战，因为它需要一个高效的催化剂来桥接单电子光子捕获过程与四电子氧气进化反应（OER）。在这里，开发了一种新的策略，通过使用层状 Co(OH)(OCH3)前体的原位相转化机制来合成无载体的超小钴氧化物纳米立方烷。在超声作用下，前体在 NaHCO3-Na2SiF6 缓冲溶液的存在下被剥离并转化为钴氧化物纳米立方烷。所得的钴催化剂平均粒径小于 2nm，在光催化水氧化中每钴每秒的周转频率为 0.023。X 射线吸收结果表明了一种独特的纳米立方烷结构，其中 13 个钴原子完全与氧配位，形成八面体排列的 8 个 Co4O4 立方烷，这可能是其具有异常高的 OER 活性的原因。
