MOF-bismuth ferrite semiconductor composites: Electrochemical insights for piezocatalytic and photocatalytic water treatment applications

The development of multi-functional catalytic materials is critical for advancing environmental remediation technologies. In this study, bismuth ferrite (BFO) was integrated with two commercially available metal-organic frameworks (MOFs), Fe-BTC and Cu-BTC, to form novel MOF/BFO semiconductor composites. These materials were evaluated for their optical, electrochemical, and catalytic activity under photocatalysis, piezocatalysis, and piezo-photocatalysis. Incorporation of Fe-BTC MOF into the BFO structure improved conductivity, light absorption, and interfacial charge separation leading to 76% norfloxacin (NFX) removal under photocatalysis and 75% removal under piezo-photocatalysis in 60 minutes. Integration of Cu-BTC into the BFO structure improved material conductivity and yielded the lowest charge transfer resistance, enabling 60% NFX removal under piezocatalysis. However, its photocatalytic performance was limited due to higher charge recombination and a lower current density under light irradiation. Electrochemical analyses confirmed that the integration of either Fe-BTC or Cu-BTC MOF into BFO material significantly enhanced charge transfer behavior and increased redox activity in comparison to pristine BFO catalyst. These findings provide valuable insight into the electrochemical behavior and catalytic potential of MOF-Bismuth semiconductor materials, establishing a platform for expanding advanced oxidation processes and broader electrochemical applications in water.