Boosting photon-generated carrier migration process through intercalation strategy for highly photoelectric performance photo-responsive Zinc-Ion batteries

The serious mismatch between the photogenerated charge migration rate and the redox reaction rate is a major limitation to the properties of photo-responsive zinc-ion batteries (PZIBs). Organic molecular intercalation can induce uniform and stable lattice structure modulation through hydrogen bonding. In this work, 2-methylimidazole intercalated V₂O₅ photocathode (NVO) is designed. Energy band structure and charge delocalization modulation is achieved by the interaction of 2-methylimidazole with oxygen atoms in V₂O₅ through hydrogen bonding. The theoretical calculation indicates that the overlap of the transition metal atomic orbitals in NVO is significantly enhance, which results in a decrease in the band gap and a lower energy barrier for carrier migration. The enhancement of the electron state density of NVO facilitates the carrier separation and migration properties, thereby reducing the probability of carrier recombination. The experimental results show that the NVO-50 photocathode, under simulated solar irradiation, exhibits a discharge capacity growth rate of 44 % at a current density of 0.5 A g^-1, surpassing previously reported vanadium-based materials. This research offers novel insights into the development of highly photoelectric properties organic molecular intercalation photocathode materials, which can facilitate the advancement of photo-responsive zinc-ion batteries.