Electrospinning Preparation of Nanostructured g-C3N4/BiVO4 Composite Films with an Enhanced Photoelectrochemical Performance.

Nanostructured g-C3N4/BiVO4 composite films with an enhanced photoelectrochemical (PEC) performance have been fabricated via the facile electrospinning technique. The g-C3N4 nanosheets can not only form heterojunctions with BiVO4 but also prevent the agglomeration of BiVO4, helping the formation of nanostructures. The as-prepared g-C3N4/BiVO4 films exhibit good coverage and stability. The PEC performance of the g-C3N4/BiVO4 films is much more enhanced compared with that for individual BiVO4 films because of the enhanced electron-hole separation. The photocurrent density is 0.44 mA/cm2 for g-C3N4/BiVO4 films at 0.56 V in the linear sweep current-voltage test, over 10 times higher than that of individual BiVO4 films (0.18 mA/cm2). The effects of the preparation conditions including the g-C3N4 content, collector temperature, calcination temperature, and electrospinning time on the PEC performance were investigated, and the reasons for the effects were proposed. The optimal preparation condition was with 3.9 wt % g-C3N4 content in the electrospinning precursor, 185 °C collector temperature, 450 °C calcination temperature, and 40 min electrospinning time. The excellent PEC performance and the facile preparation method suggest that the g-C3N4/BiVO4 films are good candidates in energy and environmental remediation area.