LAUSR

Abstract In this study, a self-powered photoelectrocatalytic (PEC) device was designed using multi-walled carbon nanotubes (CNTs) and methylamine (CH3NH2) modified perovskite solar cells (PSCs) as the power source and CNT/TiO2 as the photoanodes. In the PSCs, CNTs and CH3NH2 were used to modify the interface between the perovskite and carbon electrode to improve the photoelectronic performance. In particular, CH3NH2 induced surface-healing of the CH3NH3PbI3 perovskite thin films and the CNTs acted as a charge transport pathway among individual perovskite nanoparticles to facilitate the collection of photogenerated holes by the carbon electrode. A power conversion efficiency of 10.39% was achieved after modification with the CNTs and CH3NH2. In the photoanodes, the CNT-modified TiO2 electrode accelerated the electron–hole separation and transportation, thereby improving the degradation performance. After assembling the PSCs modified using CNT and CH3NH2 with CNT/TiO2, the solar-driven PEC system exhibited a high PEC degradation rate with rhodamine B (RhB). The optimal degradation efficiency for RhB with the tandem device was close to 100% after 80 min. This low-cost tandem assembly has promising applications in pollutant degradation research.