Li Da-Huan, Zhang Xiao-Yue, Lv Jiang-Quan, Cai Ping-Wei, Sun Yan-Qiong, Sun Cai, Zheng Shou-Tian
Fujian Provincial Key Laboratory of Advanced Inorganic Oxygenated-Materials, College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350108, China.
College of Electronics and Information Science, Fujian Jiangxia University, Fuzhou, Fujian, 350108, China.
Angew Chem Int Ed Engl. 2023 Nov 13;62(46):e202312706. doi: 10.1002/anie.202312706. Epub 2023 Oct 12.
Inspired by the metal-oxo cluster structural feature and charge separation behaviour of the oxygen evolving center (OEC) in photosystem II (PS-II) under photoirradiation, a new crystalline photochromic polyoxomolybdate, MV [β-Mo O ] (1, MV=methyl viologen cation), is designed as a biomimetic oxygen evolution reaction (OER) catalyst in neutral electrolytes. After photoinduced electron transfer (PIET) with colour change from colourless to grey, it remains in an ultra-stable charge-separated state over a year under ambient conditions. The observed overpotential at 10 mA ⋅ cm and Tafel slope decrease by 49 mV and 62.8 mV ⋅ dec after coloration, respectively. The outstanding OER performance of the coloured state in neutral electrolytes even outperforms the commercial RuO benchmark. Experimental and theoretical studies show that oxygen holes within polyanions after irradiation serve as sites for enhancing direct O-O coupling, thus effectively promoting OER. This is the first successful application of electron-transfer photochromism to realize OER activity gain.
受光照射下光系统II（PS-II）中析氧中心（OEC）的金属-氧簇结构特征和电荷分离行为的启发，设计了一种新型结晶光致变色多金属氧酸盐MV[β-Mo₈O₂₆]（1，MV = 甲基紫精阳离子）作为中性电解质中的仿生析氧反应（OER）催化剂。经过光致电子转移（PIET）后颜色从无色变为灰色，在环境条件下它在一年多的时间里保持超稳定的电荷分离状态。在10 mA·cm⁻²时观察到的过电位和塔菲尔斜率在着色后分别降低了49 mV和62.8 mV·dec⁻¹。中性电解质中着色态出色的OER性能甚至优于商业RuO₂基准。实验和理论研究表明，辐照后聚阴离子内的氧空穴作为增强直接O-O耦合的位点，从而有效地促进了OER。这是电子转移光致变色首次成功应用于实现OER活性增益。
