Substantially enhanced front illumination photocurrent in porous SnO2 nanorods/networked BiVO4 heterojunction photoanodes. Issue 30 (12th July 2018) - Bhat, Swetha S. M.
Abstract : The porous SnO2 nanorods/networked BiVO4 heterojunction is identified as apromising photoanode which exhibits high photocurrent under front illumination.The interplay of porous SnO2 NRs and optimum coverage of BiVO4 lead to high PEC performance. Abstract : BiVO4 is a promising photoanode for photoelectrochemical applications owing to its suitable band edge position for oxygen evolving reactions. High photocurrent under front illumination is very much essential to design tandem structures with a wireless configuration. However, the performance of BiVO4 under front illumination is limited due to poor charge transport properties. Here, we show that network-like BiVO4 coupled with porous SnO2 nanorods (NRs) is a promising model to enhance the front illumination performance. A very high photocurrent density of 5.6 mA cm −2 and 5.5 mA cm −2 has been obtained from the front and back illumination at 1.23 V vs. the reversible hydrogen electrode, respectively. We demonstrate that the appropriate nanostructuring of SnO2 NRs/BiVO4 is the underlying technology to tune the performance under directional illumination. The SnO2 NRs/BiVO4 exhibits a maximum incident photon to current efficiency of ∼80% under front and back illumination. A systematic study reveals that the optimized network like BiVO4 coated on porous SnO2 NRs synergistically boosts both the charge separation and transfer efficiencies of the photoanode resulting in a significantly high photocurrent for illumination on either side. This work provides a direction to achieve enhanced photocurrent during front and back side illumination in order to realize a wireless tandem configuration.