Higher Yield Urea-Derived Polymeric Graphitic Carbon Nitride with Mesoporous Structure and Superior Visible-Light-Responsive Activity

Abstract

A series of mesoporous graphitic carbon nitride (mg-C3N4) materials have been prepared with urea and tetraethylorthosilicate (TEOS) as the precursors, which were thermally polycondensed to obtain the g-C3N4/silica composites, after silica was removed, mg-C3N4 with large surface area (170 m2 g–1) was successfully prepared. Excitingly, TEOS did not only act as a mesoporous-directing agent but also as the promoter for the urea polycondensation to g-C3N4, which made the urea polycondensation proceed at relatively low temperature. Thus, volatilization or/and decomposition of urea in the process of thermal treatment were reduced, resulting in the product yield of g-C3N4 from 0.3 to 0.4 g/10 g urea remarkably increasing to 1.2 g/10 g urea. Moreover, superior photocatalytic activities were observed for degrading methyl orange (MO) and H2 generation from water splitting over the mg-C3N4 photocatalyst. The facilely developed method for high-yield mesoporous g-C3N4 from cost-effective urea was more attractive for its wide applications in environmental treatment and energy development fields.

Synthesis of barbituric acid doped carbon nitride for efficient solar-driven photocatalytic degradation of aniline

“…However, the photocatalytic activity of CN versus the degradation organic pollutants is quite low because of its relatively fast charge recombination and insufficient absorption in the visible-light spectral range. To improve the photocatalytic performance of CN, various modification methods have been applied through structure regulation [10][11][12][13][14][15][16][17][18][19], doping [20][21][22][23][24][25][26][27], surface hetero-junction and copolymerization [28][29][30][31][32][33][34][35][36][37]. Among those methods, copolymerization of CN has been regarded as an efficient route, not only for obtaining an enhance light-absorption, but also for creating surface hetero-structures which could reduce the recombination of photogenerated electron-holes.…”

Fabrication and Evaluation of Multi‐Walled Carbon Nanotubes Supported Novel Catalyst for Select Conversion of Cellulose to 5‐Hydroxymethylfurfural

“…The N 1s spectra of CNTs−SO 3 H−NH 2 and CNTs−SO 3 H−NH 2 −Cr III catalysts were exhibited in Figure c. The N 1s spectrum of CNTs−SO 3 H−NH 2 −Cr III catalyst also showed a shift to a litter higher binding energy after the successful grafting of Cr III species. And the big peak appeared around at 400 eV was attributed to N atom sp 2 ‐bonded to tertiary nitrogen ( N −(C) 3 ) and amino functional group (−NH 2 ) with hydrogen atom . These results indicated the successful grafting of acid‐base groups and Cr III species over mesoporous CNTs supporter for multi‐functional catalysts synthesis.…”

Construction of Large‐Scale Ultrathin Graphitic Carbon Nitride Nanosheets by a Hydrogen‐Bond‐Assisted Strategy for Improved Photocatalytic Hydrogen Production and Ciprofloxacin Degradation Activity

“…The C/N ratio of pristine g‐C 3 N 4 was 0.635, which is less than the theoretical value of 0.75. The lower ratio of C/N could be ascribed to the partially polymerized structure of pristine g‐C 3 N 4 . The C/N ratio of ultrathin NS g‐C 3 N 4 was 0.646, which is slightly higher than that of pristine g‐C 3 N 4 and suggests a better condensation of the tri‐ s ‐triazine structure in ultrathin NS g‐C 3 N 4 .…”