Amide Covalent Bonding Engineering in Heterojunction for Efficient Solar-Driven CO₂ Reduction

Abstract

Inefficient charge separation and slow interfacial reaction dynamics significantly hamper the efficiency of photocatalytic CO 2 reduction. Herein, a facile EDC/NHS-assisted linking strategy was developed to enhance charge separation in heterojunction photocatalysts. Using this approach, we successfully synthesized amide-bonded carbon quantum dot-g-C 3 N 4 (CQD-CN) heterojunction photocatalysts. The formation of amide covalent bonds between CN and CQDs in the CN-CQD facilitates efficient carrier migration, CO 2 adsorption, and activation. Exploiting these advantages, the CN-CQD photocatalysts exhibit high selectivity with CO and CH 4 evolution rates of 79.2 and 2.7 μmol g −1 h −1 , respectively. These rates are about 1.7 and 3.6 times higher than those of CN@ CQD and bulk CN, respectively. Importantly, the CN-CQD photocatalysts demonstrate exceptional stability, even after 12 h of continuous testing. The presence of the COOH* signal is identified as a crucial intermediate species in the conversion of CO 2 to CO. This study presents a covalent bonding engineering strategy for developing high-performance heterojunction photocatalysts for efficient solar-driven reduction of CO 2 .

Cd0.9La0.1S/graphdiyne type-II heterojunction structure for efficient photocatalytic hydrogen production

“…The decay data of TRPL are fitted by a double exponential function (eqn (1)), and the average lifetime of carriers is calculated by eqn (2). 53 As shown in Table 2, the average lifetimes of Cd 0.9 La 0.1 S, CLGY-20%, and GDY are 0.0459, 0.0044 and 0.0271 ns, respectively. After the introduction of GDY into Cd 0.9 La 0.1 S, the average lifetime decreased.…”

Photocatalytic production of H2O2 from wastewater under visible light by chlorine and ZnIn2S4 co-decorated TpPa-1

“…22,23 More importantly, the extraneous functional groups on COFs could serve as an active site to bind with guest molecules such as semiconductors to form intimate heterostructure, which is expected to further elevate the separation and transfer efficiencies of photo-excited charge carriers. 8,24 Whereas, the reported COF-based heterostructures were mostly constructed via direct combination, 25,26 and in this case, the issue of weak interfacial compatibility should be a matter of concern.…”

A graphitic carbon nitride photocatalyst with a benzene-ring-modified isotype heterojunction for visible-light-driven hydrogen production

“…Heterojunction composites therefore minimize the rate of charge carrier recombination, maximize visible light utilization, and viably enhance the photocatalytic efficiency of g-C 3 N 4 . [47][48][49] Notably, constructing isotype heterojunctions of g-C 3 N 4 with distinct band structures within its two dissimilar crystal phases is effective in facilitating the separation of photogenerated charge carriers. For instance, Sundaram et al created isotype heterojunctions of g-C 3 N 4 through a one-step thermal treatment of melamine-urea, melamine-thiourea, and ureathiourea mixtures to achieve superior, stable visible-lightinduced photocatalytic degradation of methylene blue dye.…”