Exfoliation of Graphitic Carbon Nitride for Enhanced Oxidative Desulfurization: A Facile and General Strategy

Abstract

A series of graphitic carbon nitride (CN) in the form of nanosheets with porous structure have been prepared through thermal treatment of bulk CN in air. Compared with the bulk counterpart, the as-generated holey CN nanosheets are larger in specific surface area. Endowed with more active sites and enhanced mass transport ability, the latter display catalytic performance substantially superior to the former, exhibiting higher H2S conversion and S selectivity in the oxidation of H2S to S. Moreover, the CN nanosheets show much better durability than traditional catalysts. It is envisaged that the strategy is a general technique that can be extended to produce porous CN nanosheets from other nitrogen-rich precursors, as well as to prepare other 2D carbon-based materials for potential applications.

Electronic Regulation of Bromophenyl Grafted Metal‐Free Carbon Nitride Catalysts for Enhanced Utilization of H2S

“…N 2 adsorption‐desorption isotherms were measured to analyze the texture of CNU and CNU‐Br x further. All of the samples exhibit Type H1 hysteresis loops (Figure S7), which is characteristic of mesoporous structure, [41,42] and thus consistent with the TEM observation. Such a porous structure is beneficial for catalytic reactions because of efficient mass transport within the internal voids.…”

Highly Active and Sulfur‐Resistant Fe–N4 Sites in Porous Carbon Nitride for the Oxidation of H2S into Elemental Sulfur

“…The atomic force microscopic image in Figure S10 in the Supporting Information shows that the laminar structure of Fe‐CNN4 is with nanoscale pores, and the thickness of the nanosheets is 0.85–0.90 nm, which corresponds to two to three atomic layers of aromatic CN. [ 27 ] The Brunauer–Emmett–Teller surface areas of Fe‐CNNχ catalysts are 213.9–308.1 m 2 g −1 , which are roughly 6.3–9.1 times that of pristine CN (34.1 m 2 g −1 ). The pore size distribution curves of Fe‐CNNχ catalysts are in the range of 3.5–5.0 nm, suggesting the existence of mesopores (Figure S11, Supporting Information and Table 1 ).…”

“…Polymeric carbon nitride (CN) was considered promising for the oxidative desulfurization in previous studies. [25][26][27][28][29] The CN is composed of infinite 2D layers of repeating tri-s-triazinebased "melon" rings. [30][31][32] Incomplete polymerization of CN would result in edges and/or defects sites, which are capable of anchoring metal atoms.…”

Element-doped graphitic carbon nitride: confirmation of doped elements and applications

“…Therefore, tremendous efforts have been made to overcome the shortages above, containing preparation of g-CN-based composites, modification of precursors, post-treatment of g-CN, exfoliation, element doping, and so on. [20][21][22][23][24][25][26][27][28][29] Element doping is a potential strategy to enhance the performance of g-CN, thus the doping of various elements has been reported in recent years. Different from g-CN-based composites, element-doped g-CN always involves the changes of the microstructure of g-CN, such as loss of graphitic structure 30 and impact to the in-plane ordering of tri-s-triazine units.…”