Efficient solar water splitting is achieved by a nanocone BiVO ₄ photoelectrochemical cell in tandem with a perovskite solar cell.

A novel organometal halide perovskite (CH₃NH₃PbI₂Br) is synthesized and used as a visible light absorber to sensitize one-dimensional (1D) TiO₂ nanowire arrays (NWAs) for all-solid-state hybrid solar cells. It achieved a power conversion efficiency (PCE) of 4.87% and an open circuit voltage (V_oc) of 0.82 V, both higher than those of its analogue CH₃NH₃PbI₃.