Band engineering of Sm/Co Co-doped BiFeO3 for enhanced pollutant degradation and hydrogen production via synergetic piezo-photocatalysis

A Sm/Co dual-doping strategy is introduced to the A and B sites of BiFeO 3 (BFO) perovskite structure to boost the synergetic piezo-photocatalytic performance for organic pollutant degradation and hydrogen production. The optimized doping ratio enables it to achieve the best balance between carrier concentration and piezoelectric response while regulating the energy band. The dual-doped sample Bi 0.9 Sm 0.1 Fe 0.8 Co 0.2 O 3 (BS 0.1 FC 0.2 O) exhibits the best piezo-photocatalytic performance, achieving a 90% RhB degradation efficiency in 60 min and hydrogen production rate of 1525 μmol g −1  h −1 . The coupling of Sm and Co co-doping in BFO effectively enhances the light harvesting and the piezoelectric polarization performance, which facilitate the generation and separation of electrons and holes. This work provides a paradigm for designing efficient piezo-photocatalysts with tailored band structures through bimetal co-doping strategies and demonstrates great potential for applications in environmental remediation and hydrogen production.