Improved Photoelectrocatalytic Performance for Water Oxidation by Earth-Abundant Cobalt Molecular Porphyrin Complex-Integrated BiVO4 Photoanode

• DOI: 10.1021/acsami.6b04510
• Publication Date: 2016-06-30T21:19:22Z
• Authors: Bin Liu; Jian Li; Hao-Lin Wu; Wen-Qiang Liu; Xin Jiang; Zhi-Jun Li; Bin Chen; Chen-Ho Tung; Li-Zhu Wu
• Keywords: Photocurrent; Reversible hydrogen electrode; Oxygen evolution

An earth-abundant, low-cost cobalt porphyrin complex (CoTCPP) is designed as a molecular catalyst to work on three-dimensional BiVO4 film electrode for water oxidation the first time. Under illumination of 100 mW cm–2 Xe lamp, CoTCPP-functionalized photoanode exhibits 2-fold enhancement in photocurrent density at 1.23 V vs RHE and nearly 450 mV cathodic shift 0.5 mA cm−2 relative bare 0.1 M Na2SO4 (pH = 6.8). Simultaneously, stoichiometric oxygen hydrogen are generated with faradic efficiency 80% over 4 h. The activity stability dramatically increased by CoTCPP, giving rise higher performance than previously reported noble metal ruthenium complex-modified photoanode. By using peroxide hole scavenger, we demonstrate that CoTCPP greatly suppresses hole–electron recombination surface semiconductor, which offers promising route toward high efficiency, low cost, practical solar fuel generation device.