Triggering Dual Two‐electron Pathway for H2O2 Generation by Multiple [Bi−O]n Interlayers in Ultrathin Bi12O17Cl2 towards Efficient Piezo‐self‐Fenton Catalysis

Piezo-self-Fenton system (PESF) has been emerging as a promising water treatment technology but suffering from unsatisfied H₂ O₂ production efficiency. Herein, we rationally design a Bi₁₂ O₁₇ Cl₂ piezo-catalyst with multiple [Bi-O]_n interlayers towards highly efficient H₂ O₂ production. The introduction of [Bi₃ O_4.25 ] layers initiates dual two-electron pathway for H₂ O₂ generation by altering the interlayer properties. It is found that the additional [Bi₃ O_4.25 ] layers not only enhance the polarization electric field but also serve as active sites for triggering dual pathways of two-electron O₂ reduction and H₂ O oxidation reaction for H₂ O₂ production. Therefore, the Bi₁₂ O₁₇ Cl₂ exhibits an ultrahigh rate of H₂ O₂ generation (7.76 mM h^-1 g^-1 ) in pure water. Based on the adequate H₂ O₂ yield, a PESF was constructed for acetaminophen (ACE) degradation with an apparent rate constant of 0.023 min^-1 . This work not only presents a potential strategy of tuning the activity of bismuth based piezo-catalysts but also provides a good example on the construction of highly efficient PESF for environmental remediation by using natural mechanical energy.