Enhanced Photocatalytic Properties of All-Organic IDT-COOH/O–CN S-Scheme Heterojunctions Through π–π Interaction and Internal Electric Field

Abstract

Herein, we present a distinct methodology for the in situ electrostatic assembly method for synthesizing a conjugated (IDT-COOH)/oxygen-doped g-C 3 N 4 (O−CN) S-scheme heterojunction. The electron delocalization effect due to π−π interactions between O−CN and self-assembled IDT-COOH favors interfacial charge separation. The self-assembled IDT-COOH/O−CN exhibits a broadened visible absorption to generate more charge carriers. The internal electric field between the IDT-COOH and the O−CN interface provides a directional charge-transfer channel to increase the utilization of photoinduced charge carriers. Moreover, the active species ( • O 2 − , h + , and 1 O 2 ) produced by IDT-COOH/O−CN under visible light play important roles in photocatalytic disinfection. The optimum 40% IDT-COOH/O−CN can kill 7-log of methicillin-resistant Staphylococcus aureus (MRSA) cells in 2 h and remove 88% tetracycline (TC) in 5 h, while O−CN only inactivates 1-log of MRSA cells and degrades 40% TC. This work contributes to a promising method to fabricate all-organic g-C 3 N 4 -based S-scheme heterojunction photocatalysts with a wide range of optical responses and enhanced exciton dissociation.

Photoinduced Stitching of Self-Assembled Triangular Silver Nanoprisms at the Air–Water Interface

“…To understand chemical changes to the ODA monolayer under light exposure, we conducted XPS analyses on 1 ML of ODA-AgTNP LB films. The C 1s core level spectra (Figure ) revealed a distinct difference between the light and dark LB films and could be decomposed into two chemically distinct components at 285 eV (C–H carbon) and ∼288 eV (carbon in −COOH, −C–NH 2 , and −CONH– (amide) bonds). − The higher binding energy component clearly increases in intensity, broadens, and shifts to a higher binding energy (∼0.3 eV) for films exposed to light (see Figures and S11). This suggests that light promotes the reaction between the carboxylic groups (−COOH) from AgTNP surface-bound citrate and the amine groups (−NH 2 ) from ODA, which is known to be thermodynamically unfavorable under ambient dark conditions.…”