Su Feng-Yun, Zhang Wei-De
School of Chemistry and Chemical Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, People's Republic of China.
Chem Asian J. 2017 Mar 2;12(5):515-523. doi: 10.1002/asia.201601518. Epub 2017 Jan 31.
Carbonyl-grafted g-C N porous nanosheets (COCNPNS) were fabricated by means of a two-step thermal process using melamine and oxalic acid as starting reagents. The combination of melamine with oxalic acid to form a melamine-oxalic acid supramolecule as a precursor is key to synthesizing carbonyl-grafted g-C N . The bulk carbonyl-grafted g-C N (COCN) was further thermally etched onto porous nanosheets by O under air. In such a process, the carbonyl groups were partly removed and the obtained sample showed remarkably enhanced visible-light harvesting and promoted the separation and transfer of photogenerated electrons and holes. With its unique porous structure and enhanced light-harvesting capability, under visible-light illumination (λ>420 nm) the prepared COCNPNS exhibited a superior photocatalytic hydrogen evolution rate of 83.6 μmol h , which is 26 times that of the p-CN obtained directly from thermal polycondensation of melamine.
采用两步热法，以三聚氰胺和草酸为起始试剂制备了羰基接枝的g-CN多孔纳米片（COCNPNS）。三聚氰胺与草酸结合形成三聚氰胺-草酸超分子作为前驱体是合成羰基接枝g-CN的关键。通过在空气中用O对块状羰基接枝g-CN（COCN）进行热蚀刻，将其进一步蚀刻到多孔纳米片上。在这个过程中，羰基部分被去除，所得样品表现出显著增强的可见光捕获能力，并促进了光生电子和空穴的分离与转移。凭借其独特的多孔结构和增强的光捕获能力，在可见光照射（λ>420 nm）下，制备的COCNPNS表现出优异的光催化析氢速率，为83.6 μmol h，是直接由三聚氰胺热缩聚得到的p-CN的26倍。
