Scaling up BiVO₄ Photoanodes on Porous Ti Transport Layers for Solar Hydrogen Production

Abstract

Commercialization of photoelectrochemical (PEC) water‐splitting devices requires the development of large‐area, low‐cost photoanodes with high efficiency and photostability. Herein, we address these challenges by using scalable fabrication techniques and porous transport layer (PTLs) electrode supports. We demonstrate the deposition of W‐doped BiVO4 on Ti PTLs using successive‐ionic‐layer‐adsorption‐and‐reaction methods followed by boron treatment and chemical bath deposition of NiFeOOH co‐catalyst. The use of PTLs that facilitate efficient mass and charge transfer, allowed the scaling of the photoanodes (100 cm2) while maintaining ~90% of the performance obtained with 1 cm2 photoanodes for oxygen evolution reaction i.e. 2.10 mA cm‐2 at 1.23 V vs. RHE. This is the highest reported performance to date. Integration with a polycrystalline Si PV cell leads to bias‐free water splitting with a stable photocurrent of 208 mA for 6 h and 2.2% solar‐to‐hydrogen efficiency. Our findings highlight the importance of photoelectrode design towards scalable PEC device development.

Biofuels and hydrogen production: back to the Langmuir–Blodgett approach for large-scale structuration of Bi-based photoelectrodes

“…Several approaches have been employed to design such electrodes, including vacuum methods (PVD, CVD), atomic layer deposition, electrodeposition, hydrothermal, spray pyrolysis, and dip-coating. Patil et al 22 recently designed BiVO 4 photoanodes on Ti porous transport layers through an electrodeposition approach and tested several geometries to determine their impact on photocatalytic performance. The results demonstrated a reduced loss of performance between small (1 cm 2 ) and large (100 cm 2 ) photoanodes, and a combination with a commercial polycrystalline Si PV led to 6 h of stability in photocurrent production (208 mA), representing a 2.2% yield.…”

“…Long-term studies demonstrating prototype stability and scale-up potential fail to observe any performance degradation regarding the benchtop. Even if the recent study by Kunturu et al 22 is an excellent example of scaling up BiVO 4 photoelectrodes, as we have commented above, more work should be implemented to provide a statistical and robust opinion for the potential to industrialize BiVO 4 photoelectrodes, following, if possible, the good practices proposed with the data reporting, 53 particularly in the case of catalyst comparison.…”