NiFe oxyhydroxide decorated TiO2 nanotube photoanodes for improved photoelectrochemical oxidation performance

Developing highly efficient and durable semiconductor photoelectrodes has become a great significance for the synthesis of clean fuels and valuable chemical products via photoelectrochemical (PEC) cell. Herein, TiO2 nanotube array–supported amorphous cocatalyst NiFe oxyhydroxides (NiFe-OOH/TiO2 NTs) were constructed by the electrodeposition method. Surprisingly, the prepared amorphous NiFe oxyhydroxides were uniformly decorated on the surface of TiO2 nanotubes without the agglomeration, which were conducive to the separation and transfer of photogenerated carriers. These nanoarchitectonics of NiFe-OOH/TiO2 NTs were favorable for promoting both the water oxidation and the selective oxidation of benzyl alcohol (BA). NiFe-OOH/TiO2 NTs demonstrated admirable stability for the water oxidation, reaching the photocurrent density of 0.49 mA cm−2 at 1.23 V vs. RHE. Furthermore, the conversion efficiency and the selectivity of BA to benzaldehyde under neutral conditions were as high as 67.7% and 84.7%, respectively. This work may provide a simple method for preparing efficient and durable photoelectric electrodes to improve the oxidation performance of PEC cell. Graphical abstract: [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Springer Nature B.V.