Tuning Light‐Driven Water Splitting Efficiency of Mo‐Doped BiVO4: Optimised Preparation and Impact of Oxygen Evolution Electrocatalysts. Issue 24 (20th November 2019)

• Record Type: Journal Article
• Authors: Junqueira, João R. C.; Bobrowski, Tim; Krysiak, Olga A.; Gutkowski, Ramona; Schuhmann, Wolfgang
• Is Part Of: ChemCatChem. Volume 11:Issue 24(2019)
• Page Start: 6417
• Page End: 6424
• Publication Date: 2019-11-20
• Subjects: Bismuth vanadate -- Mo-doped bismuth vanadate -- photoelectrocatalysis -- oxygen evolution catalyst -- oxygen evolution; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201901646
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: We present airbrush spray‐coating as a reproducible method for the preparation of Mo‐doped BiVO4 (Mo : BiVO4 ) as photoabsorber with different layer thicknesses and Mo content. Optimisation of layer thickness is aiming on diminishing limitations by the electronic conductivity within the photoabsorber, thus increasing the incident photon to current efficiency (IPCE) of the samples. Furthermore, the Mo to V ratio leading to the highest photocurrent density was determined, and the optimised Mo : BiVO4 samples were decorated with a variety of oxygen evolution reaction (OER) electrocatalysts such as cobalt phosphate and layered double hydroxides. A mass loading gradient of Ni−Fe LDH was sprayed on top of the Mo : BiVO4 photoanode for optimisation of the OER catalyst loading. The photocurrent density was enhanced by up to 5.8 times at 0.8 V vs . RHE in comparison with the pristine Mo : BiVO4 sample in absence of any OER electrocatalyst. Abstract : Improving photoelectroactivity : A systematic and optimised fabrication of Mo‐doped BiVO4 photoanodes using spray coating is reported. Control of layer thickness and of the Mo to V ratio improves the photoelectroactivity. Fabrication of a mass‐loading gradient of Ni−Fe LDH combined with local optical droplet cell measurements led to an enhanced photocurrent density of 5.8 times.