Enhanced Photoelectrochemical Water Oxidation on BiVO4 Photoanodes Functionalized by Bimetallic Dicyanamide Molecular Catalysts

A novel hybrid structure of bimetallic dicyanamide decorated BiVO4 is developed via a simple method to accelerate interfacial water oxidation kinetics. Two types dicyanamides, CoNi(dca)2 and CoFe(dca)2, are coated on photoanodes found exhibit far more enhanced PEC performance than Co(dca)2 or Ni(dca)2 as cocatalysts. The successful deposition metal dicyanamides confirmed by physical characterizations including X-ray photoelectron spectroscopy (XPS). optimized Co0.9Ni0.1(dca)2/BiVO4 photoanode exhibits the highest photocurrent density 2.58 mA/cm2 at 1.23 V vs. RHE under 100 mW/cm2 AM 1.5 G irradiation, which 2.5 times that bare BiVO4. substantial enhancement can be ascribed advantageous charge transfer improved injection efficiencies. This work presents feasible strategy using different design modified BiVO4-based system for efficiency.