文献速递|山东大学ACB:揭示新型 p-n 异质结 Mn3O4-C3N4 在压电催化下高效活化亚氯酸盐降解有机污染物的反应机理

第一作者：Qichi Feng, Zhen Liu

通讯作者：李倩 教授

通讯单位：山东大学环境科学与工程学院

DOI:10.1016/j.apcatb.2024.124714

Fig. 1. (a) Schematic diagram of preparation of CN and Mn3O4-CN; (b) SEM image, (c-d) HRTEM images, and (e) EDS mapping image of Mn3O4-CN. (f) XRD patterns of CN and Mn3O4-CN catalysts; high-resolution XPS spectra of (g) C 1 s, (h) N 1 s, and (i) O 1 s of CN and Mn3O4-CN; (j) high-resolution XPS spectrum of Mn 2p of Mn3O4-CN.

Fig. 2. SMX degradation performance in different (a) catalysts/chlorite system and (b) piezo/catalysts/chlorite system. (c) Comparison of degradation rate of SMX in different systems. (d) Effect of ultrasonic powers on SMX degradation in the piezo/Mn3O4-CN/chlorite system. Experimental conditions: [catalyst]0 = 0.5 g/L, [chlorite]0 = 1 mM, [SMX]0 = 10 mg/L, pH = 6.5.

Fig. 3. (a) Effect of different quenching agents on SMX removal in the piezo/Mn3O4-CN/chlorite system. (b) UV–vis absorption spectra of the products of NBT probe. (c) Conversion rate of PMSO to PMSO2 in different systems. EPR signals for (d) DMPO-·OH, (e) DMPO-·O2–, (f) TEMP-1O2, (g) TEMPO-h+ and (h) DMPO-ClO2 in the piezo/Mn3O4-CN/chlorite system. (i) ClO2 production in different systems.

Fig. 4. (a) Surface topography images and PFM amplitudes of Mn3O4-CN. (b) Amplitude loops and phase loops of Mn3O4-CN. (c) CV plots of Mn3O4-CN; (d) EIS of CN and Mn3O4-CN. (e) piezoelectric currents in different systems. (f) UV–vis diffuse reflectance spectra. (g) valence band XPS (VB-XPS) and (h) ultraviolet photoelectron spectroscopy (UPS) spectra of CN, Mn3O4 and Mn3O4-CN. (i) Schematic diagram of band structure of CN, Mn3O4 and Mn3O4-CN samples (before contact and after contact). (j) Schematic diagram of piezoelectric catalysis of Mn3O4-CN under compressive and tensile strains.

Fig. 5. (a) Models of CN/ClO2–, Mn3O4/ClO2– and Mn3O4-CN/ClO2–. Adsorption energy and Cl-O bond length for (b) CN/ClO2–, (c) Mn3O4/ClO2– and (d) Mn3O4-CN/ClO2–. (e) The charge density difference with an isosurface value of 0.005 e/Å. (f) Charge density and charge transfer of CN and Mn3O4 adsorb chlorite. (g) Charge density and charge transfer of Mn3O4-CN adsorb chlorite. (h) DOS of different elements of Mn3O4-CN after adsorption of chlorite. (i) The mechanically mediated chlorite activation on the surface of Mn3O4-CN (reductive cleavage and homolytic cleavage of the Cl-O bond). (j) The Gibbs energy (∆G), enthalpy (∆H), and electronic energy (∆E) for the breakage of Cl-O bond in different systems. (k) Mn 2p XPS of Mn3O4-CN, Mn3O4-CN after piezo and Mn3O4-CN after reaction. (l) Mechanism of SMX degradation by a combined piezo/Mn3O4-CN/chlorite process.

Fig. 6. (a) Effect of pH on SMX degradation. (b) Effect of anions and HA on SMX degradation. (c) The degradation performance of different pollutants. (d) Cycle stability of the piezo/Mn3O4-CN/chlorite system. (e) TOC removal efficiencies in different systems. Conversion of chloride-containing ions in the piezo/Mn3O4-CN/chlorite system (f) without SMX and (g) with SMX.