Modulate surface potential well depth of Bi12O17Cl2 by FeOOH in Bi12O17Cl2@FeOOH heterojunction to boost piezoelectric charge transfer and piezo-self-Fenton catalysis

Abstract

Although the design of heterojunction piezoelectric catalysts has significantly enhanced catalytic activity, the regulatory mechanisms of heterojunction interfaces on surface potential wells during piezoelectric processes and their impact on carrier migration still lack systematic investigation. This work constructs an enhance interface interaction heterointerface between amorphous FeOOH and Bi₁₂O₁₇Cl₂ (BOC) in Bi₁₂O₁₇Cl₂@FeOOH through a self-assembly strategy. This strong interfacial interaction significantly enhances interface polarity can substantially suppress the stress-responsive capability of surface charges on BOC (maximum reduction reached as high as 63 %–98 % of original value). This significantly reduces the depth of surface potential wells during piezoelectric processes, thereby effectively weakening piezoelectric charge confinement while promoting charge transfer. Concurrently, Bi–O–Fe chemical bonds formed at the interface and establish charge transport channels. These synergistic mechanisms elevate the H₂O₂ production rate to 3.04 mmol g⁻¹ h⁻¹ for participate in the piezoelectric self-Fenton reaction and the removal rate of total organic carbon increased 3 fold (18.6 % vs 55.8 %).