Three-Dimensional Porous Aerogel Constructed by g-C₃N₄ and Graphene Oxide Nanosheets with Excellent Visible-Light Photocatalytic Performance

Abstract

It is curial to develop a high-efficient, low-cost visible-light responsive photocatalyst for the application in solar energy conversion and environment remediation. Here, a three-dimensional (3D) porous g-C3N4/graphene oxide aerogel (CNGA) has been prepared by the hydrothermal coassembly of two-dimensional g-C3N4 and graphene oxide (GO) nanosheets, in which g-C3N4 acts as an efficient photocatalyst, and GO supports the 3D framework and promotes the electron transfer simultaneously. In CNGA, the highly interconnected porous network renders numerous pathways for rapid mass transport, strong adsorption and multireflection of incident light; meanwhile, the large planar interface between g-C3N4 and GO nanosheets increases the active site and electron transfer rate. Consequently, the methyl orange removal ratio over the CNGA photocatalyst reaches up to 92% within 4 h, which is much higher than that of pure g-C3N4 (12%), 2D hybrid counterpart (30%) and most of representative g-C3N4-based photocatalysts. In addition, the dye is mostly decomposed into CO2 under natural sunlight irradiation, and the catalyst can also be easily recycled from solution. Significantly, when utilized for CO2 photoreduction, the optimized CNGA sample could reduce CO2 into CO with a high yield of 23 mmol g(-1) (within 6 h), exhibiting about 2.3-fold increment compared to pure g-C3N4. The photocatalyst exploited in this study may become an attractive material in many environmental and energy related applications.

Synthesis of Large Surface‐Area g‐C3N4 Comodified with MnOx and Au‐TiO2 as Efficient Visible‐Light Photocatalysts for Fuel Production

“…It is confirmed mainly based on the steady-state surface photovoltage spectra, transient-state surface photovoltage responses, fluorescence spectra related to the produced • OH amount, and electrochemical reduction curves that the exceptional photoactivities are comprehensively attributed to the large surface area (85.5 m 2 g −1 ) due to the porous structure, to the greatly enhanced charge separation and to the introduced catalytic functions to the carrier-related redox reactions by decorating MnO x and coupling Au-TiO 2 , respectively, to modulate holes and electrons. [22,23] The resulting porous gC 3 N 4 could exhibit enhance efficiencies for CO 2 conversion, H 2 evolution, and pollutant degradation. area and high photogenerated charge recombination rate.…”

Construction of stable Ta 3 N 5 /g-C 3 N 4 metal/non-metal nitride hybrids with enhanced visible-light photocatalysis

“…As can be seen from C 1s spectra (Fig. 4a), the C peaks at the binding energy of 284.6 and 288.1 eV for g-C 3 N 4 are assigned to surface adventitious carbon and defect-containing sp 2 -bonded carbon, respectively [27,41]. The C ls spectrum of 2-Ta 3 N 5 /g-C 3 N 4 is similar to that of g-C 3 N 4 , but the peak at 288.1 eV in g-C 3 N 4 for defect-containing sp 2 -bonded carbon shifts 0.4 eV towards lower binding energy 12 (287.7 eV).…”

Heteroatom‐Doped Carbonaceous Photocatalysts for Solar Fuel Production and Environmental Remediation

“…These hybrid aerogels show porous, wrinkled, and fluffy structures stacked by nanosheets (Figure ). Also, they show higher S BET , promoted light absorption from multiple reflection, enhanced charge transfer and much higher recombination inhibition of charge carriers than pure g‐C 3 N 4 , which benefits enhancing photocatalytic reaction. Besides g‐C 3 N 4 /G derivatives hybrids, g‐C 3 N 4 /CDs hybrids containing appropriate amount of carbon nanodots (CDs) have also attracted great interest, owing to the unique optical and electrical properties of CDs .…”