Urabe Haruki, Hisatomi Takashi, Minegishi Tsutomu, Kubota Jun, Domen Kazunari
Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Faraday Discuss. 2014;176:213-23. doi: 10.1039/c4fd00122b. Epub 2014 Nov 19.
SrNbO(2)N photoanodes, which have a band gap energy of 1.8 eV, were tested for photoelectrochemical water oxidation in water splitting. The photoanodes were fabricated either by a particle transfer method or an electrophoretic deposition method. The effects of the precursors, fabrication method, and CoOx catalyst loading were studied in order to identify the shortcomings of the photoanodes and improve their photoelectrochemical properties for water oxidation. SrNbO(2)N photoanodes fabricated by particle transfer generated a photocurrent that was one order of magnitude higher than that of photoanodes prepared via electrophoretic deposition. The stoichiometric oxide precursor (Sr(2)Nb(2)O(7)) was found to be preferable to the Sr-rich oxide precursor (Sr(5)Nb(4)O(15)). CoOx increased the photoanodic current on SrNbO(2)N photoelectrodes. Nevertheless, the incident photon-to-current efficiency was still limited to 10% at most. Potential problems with SrNbO(2)N photoanodes were discussed.
具有1.8电子伏特带隙能量的SrNbO₂N光阳极，被用于水分解中的光电化学水氧化测试。这些光阳极通过颗粒转移法或电泳沉积法制备。研究了前驱体、制备方法和CoOx催化剂负载量的影响，以确定光阳极的缺点，并改善其用于水氧化的光电化学性能。通过颗粒转移制备的SrNbO₂N光阳极产生的光电流比通过电泳沉积制备的光阳极高一个数量级。发现化学计量比的氧化物前驱体（Sr₂Nb₂O₇）比富Sr氧化物前驱体（Sr₅Nb₄O₁₅）更可取。CoOx增加了SrNbO₂N光电极上的光阳极电流。然而，入射光子到电流效率仍最多限制在10%。讨论了SrNbO₂N光阳极存在的潜在问题。
