标题：In-situ exfoliation of porous carbon nitride nanosheets for enhanced hydrogen evolution
作者：Gao, Xiaochun; Feng, Jin; Su, Dawei; Ma, Yuchen; Wang, Guoxiu; Ma, Houyi; Zhang, Jintao
作者机构：[Gao, Xiaochun; Ma, Yuchen; Ma, Houyi; Zhang, Jintao] Shandong Univ, Minist Educ, Sch Chem & Chem Engn, Key Lab Colloid & Interface Chem, 27 South Sha 更多
通讯作者：Zhang, JT;Su, DW;Wang, GX;Zhang, Jintao
通讯作者地址：[Zhang, JT]Shandong Univ, Minist Educ, Sch Chem & Chem Engn, Key Lab Colloid & Interface Chem, 27 South Shanda Rd, Jinan 250101, Shandong, Peoples R C 更多
关键词：g-C3N4; Porous nanosheets; Heteroatom doping; Catalysis; Hydrogen; evolution
摘要：The development of water splitting technology is severely impeded by the limited strategies for preparing efficient photocatalyst with optimal structure. Herein, a facile structure and doping engineering strategy is proposed to obtain the atomic-thin mesoporous graphite carbon nitride (g-C3N4) nanosheets with a large specific surface area of 212.5 m(2) g(-1), an ultra-large pore volume of 1.55 cm(3) g(-1), high C and O contents of similar to 51.4 and 4.8% via an acid-assisted exfoliation route without any hard templates. The theoretical calculation reveals that the introduction of additional C/O atoms into g-C3N4 matrix would boost the charge transfer rate and charge separation efficiency due to the enhanced electronic polarization effect (Bader Charge) and shortened bond lengths. Additionally, the electronic conductivity is demonstrated to be enhanced due to the formation of delocalized pi-bonding both experimentally and theoretically. The synergic contribution of textural and electronic features renders an excellent photoelectrochemical (PEC) performance with 50-60 times larger photocurrent in comparison with the pristine g-C3N4 and high hydrogen evolution rates of 830.1 and 115.5 mu mol g(-1) h(-1) under the solar- and visible-light irradiation, respectively. This in-situ exfoliation approach demonstrates a facile yet efficient method to synthesize highly porous carbon nitride materials with optimal structure and composition for efficient water splitting.