Structure Engineered g‐C3N4 Nano‐Sheets by Switching the Pyrolysis Gas Atmosphere for Enhanced Photo‐Catalytic Degradation. Issue 2 (14th February 2017)

• Record Type: Journal Article
• Authors: Chai, Yuanyuan; Liu, Qianqian; Zhang, Lu; Ren, Jia; Dai, Wei‐Lin
• Is Part Of: Chinese journal of chemistry. Volume 35:Issue 2(2017)
• Page Start: 173
• Page End: 182
• Publication Date: 2017-02-14
• Subjects: g‐C3N4 -- nano‐sheets -- NH3 -- urea -- photo‐catalyst; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cjoc.201600608
• Languages: English
• ISSNs: 1001-604X

Abstract

Abstract: We developed a new one step approach to synthesize g‐C3 N4 nano‐sheets by direct thermal pyrolysis process of urea in NH3 atmosphere. For the first time, the influence of the preparation gas atmosphere on the composition, crystalline and polymerization degree, and the activity of the g‐C3 N4 synthesized from thermal condensation of urea was investigated. Impressively, the g‐C3 N4 nano‐sheets obtained under NH3 gas atmosphere exhibited much superior photo‐catalytic activities to the prepared g‐C3 N4 in air or N2, and the rate of the g‐C3 N4 ‐NH3 was about 5 times higher than that on g‐C3 N4 ‐N2 sample. The detailed characterization analysis revealed that NH3 thermal pyrolysis atmosphere contributed to the polymerization degree and the formation of the layer with a more regular structure due to the efficiently extending of the conjugated π‐conjugative system, which was favorable to the transfer of the photo‐induced charge carriers. Furthermore, we studied in depth the structure‐performance relationship in the system, and it was found that the synergistic effect of the larger surface area, the adjusted band energy structure and the well crystallization may be conductive to the higher separation of the electron–hole pair, thus leading to the wonderful performance for the g‐C3 N4 ‐NH3 . Notably, the method has the merits of low cost, scalable production and environmental friendliness. Abstract : For the first time, the influence of the preparation gas atmosphere on the composition, crystalline and polymerization degree, and the activity of the g‐C3 N4 synthesized from thermal condensation of urea was investigated. Impressively, the g‐C3 N4 nano‐sheets obtained under NH3 gas atmosphere exhibited much superior photo‐catalytic activities to the prepared g‐C3 N4 in air or N2 . Furthermore, we studied in depth the structure–property relationship in the system, and it was found that the synergistic effect of the larger surface area, the adjusted band energy structure and the good crystallization may be conductive to the higher separation of the electron–hole, thus leading to the wonderful performance for the g‐C3 N4 ‐NH3 . Notably, the method has the merits of the low cost, scalable production and environmental friendliness.