Defect-rich ultrathin poly-heptazine-imide-framework nanosheets with alkali-ion doping for photocatalytic solar hydrogen and selective benzylamine oxidation  

作　　者：Chaofeng Zhu Xiao Luo Congyan Liu Yang Wang Xihai Chen Yan Wang Qing Hu Xiaojun Wu Bo Liu 

机构地区：[1]School of Chemistry and Materials Science,University of Science and Technology of China,Hefei 230026,China [2]Synergetic Innovation of Quantum Information&Quantum Technology,CAS Key Laboratory of Materials for Energy Conversion,and CAS Center for Excellence in Nanoscience,School of Chemistry and Materials Sciences,University of Science and Technology of China,Hefei 230026,China [3]Max Planck Institute of Colloids and Interfaces,Am Mühlenberg 1,14476 Potsdam,Germany

出　　处：《Nano Research》2022年第10期8760-8770,共11页纳米研究（英文版）

基　　金：supported by the National Key Research and Development Program of the MOST(Nos.2021YFA1500400 and 2018YFA0208603);the National Natural Science Foundation of China(NSFC,Nos.21571167,51502282,22075266,and 21890751);the Fundamental Research Funds for the Central Universities(Nos.WK2060190053 and WK2060190100).

摘　　要：Polymeric carbon nitride(CN)as a metal-free photocatalyst holds great promise to produce high-value chemicals and H_(2) fuel utilizing clean solar energy.However,the wider deployment of pristine CN is critically hampered by the poor charge carrier transport and high recombination.Herein,we develop a facile salt template-assisted interfacial polymerization strategy that insitu introduces alkali ions(Na+,K+)and nitrogen defects in CN(denoted as v-CN-KNa)to simultaneously promote charge separation and transportation and steer photoexcited holes and electrons to their oxidation and reduction sites.The photocatalyst exhibits an impressive photocatalytic H_(2) evolution rate of 8641.5μmol·g^(−1)·h^(−1)(33-fold higher than pristine CN)and also works readily in real seawater(10752.0μmol·g^(−1)·h^(−1))with a high apparent quantum efficiency up to 18.5%at 420 nm.In addition,we further demonstrate that the v-CN-KNa can simultaneously produce H_(2) and N-benzylidenebenzylamine without using any other sacrificial reagent.In situ characterizations and DFT calculations reveal that the alkali ions notably promote charge transport,while the nitrogen defects generate abundant edge active sites,which further contribute to efficient electron excitation to trigger photoredox reactions.

关 键 词：carbon nitride photocatalysis alkali ion doping hydrogen production amine oxidative coupling 

分 类 号：O62[理学—有机化学]