Mesoscale Mechanism of P‐dopant Defects and Interface Synergy for Phenols Degradation

Abstract

The semiconductor based photocatalysis has become a hot spot of current research, and the key challenges are the construction of strong functional heterojunction photocatalysts, and insights on the working mechanism involved. In this work, we constructed a NiFe-LDHs/P-TCN heterojunction with P-dopant defects and interface synergy and elucidated its mesoscale mechanism among different constituent interfaces. The interface photoelectron transfer was detected by PAS, EPR and other methods, and the enhancing mechanism of the defect sites for interface electron transfer and photocatalytic activity was proposed. The interfacial electrons, photoelectric properties and photocatalytic activity are found to be positively correlated. The result is conducive for a better understanding on working mechanism of heterogeneous photocatalysts, which opened a broader research space for the rational design and construction of functional interfaces.

Synergistic Mechanism of ZnCr-LDHs/C-g-C3N4 Photocatalyst for Efficient Degradation of Antibiotics under Visible Light

“…As shown in Figure a, U–CN has the strongest fluorescence peak at about 450 nm for its easier recombination of the photogenerated carriers. However, its fluorescence signal decreased significantly after C-doping, indicating that the benzene ring that grafted to g-C 3 N 4 can effectively inhibit the recombination of photogenerated carriers After combination with ZnCr-LDHs, the separation of photogenerated carriers is further enhanced due to the synergistic effect between defects and heterostructure interfaces . The TRPL analysis indicates that the order of fluorescence lifetime follows the order of 19%ZnCr-LDHs/C–CN-550 > C–CN-550 > C–CN > U–CN (Figure b), which is consistent with the PL result.…”

“…However, its fluorescence signal decreased significantly after C-doping, indicating that the benzene ring that grafted to g-C 3 N 4 can effectively inhibit the recombination of photogenerated carriers 47 After combination with ZnCr-LDHs, the separation of photogenerated carriers is further enhanced due to the synergistic effect between defects and heterostructure interfaces. 48 The TRPL analysis indicates that the order of fluorescence lifetime follows the order of 19%ZnCr-LDHs/C−CN-550 > C−CN-550 > C−CN > U−CN (Figure 7b), which is consistent with the PL result. The electrochemical impedance spectroscopy analysis in Figure S2 shows that the Nyquist radius of C−CN and C−CN-550 is significantly reduced compared with U−CN, which indicates that C-doping significantly reduces the electron transfer impedance of the material.…”