S, Na Co-Doped Graphitic Carbon Nitride/Reduced Graphene Oxide Hollow Mesoporous Spheres for Photoelectrochemical Catalysis Application

Abstract

As an environmentally friendly visible-light-responsive and metal-free photocatalyst, the photoelectrochemical (PEC) performance of graphitic carbon nitride (CN) has still been limited by its large optical band gap, low absorption of light, and inefficient transfer of electron−hole carriers. Herein, we report an S, Na codoped CN/reduced graphene oxide (rGO) (S, Na-CN/rGO) hollow mesoporous sphere (HMS) prepared by supramolecular preorganization of monomers. The as-prepared S, Na-CN/rGO HMS is uniform with a diameter of ∼2 μm and exhibits a high specific surface area up to 92.3 m 2 g −1 , a narrow band gap of 2.26 eV, and a high PEC performance with a photocurrent density of 14.04 μA/cm 2 , which is 78-fold of bulk CN (0.18 μA/cm 2 ). The significantly enhanced PEC performance is attributed to the synergistic effect of enhanced light absorption by the multiple reflections of incident light in the unique HMS structure, the changes of the electronic structure by S, Na co-doping, and the well-conduced rGO layers in CN. The results have provided a way for realizing the practical photoelectrochemical catalysis application of CN.

Rapid Microwave Synthesis of Mesoporous Oxygen-Doped g-C3N4with Carbon Vacancies for Efficient Photocatalytic H2O2Production

“…The synthesis of the MCA precursor was reported in our previous work. 22 Typically, an equimolar ratio of melamine (0.5 g) and cyanuric acid (0.51 g) was dissolved in 100 and 50 mL of dimethyl sulfoxide (DMSO) solutions under sonication, respectively. Afterward, a solution of melamine and cyanuric acid was mixed under vigorous stirring for 10 min.…”

Directional Charge Transfer Channels in a Monolithically Integrated Electrode for Photoassisted Overall Water Splitting

“…Significantly, CCN can be integrated with the electrocatalyst as a photocatalyst component through a chemical bond owing to oxygen-containing groups on the surface of carbon dots. In comparison to the traditional heterojunction construction that has drawbacks such as poor interface interaction and low mass transfer efficiency, − the chemical bond between CCN and the electrocatalyst would serve as directional charge transfer channels, making it easier for the photogenerated charge carriers to transfer from the photocatalyst to electrocatalyst surface, which can greatly improve the interface charge transfer and effectively inhibit the recombination of photogenerated electron holes.…”

Organic–Inorganic Hybrid Near-Infrared Emitting Porous Polymer for Detection and Photodegradation of Antibiotics

“…Therefore, regulation of electron mobility by tuning the chromophores is possible. In addition, the transient photocurrent spectra (Figure b) indicate that the two samples examined in this work belong to type II transient photocurrent responses . As shown in the figure, the photocurrent gradually increases by the illumination and decreases in the dark, which indicates the generation of the nonequilibrium carriers under illumination.…”

“…In addition, the transient photocurrent spectra (Figure 9b) indicate that the two samples examined in this work belong to type II transient photocurrent responses. 62 As shown in the figure, the photocurrent gradually increases by the illumination and decreases in the dark, which indicates the generation of the nonequilibrium carriers under illumination. The photocurrent of CZ-DCM is higher than that of PCS-CZ-DCM, demonstrating that CZ-DCM could lead to a more efficient photogenerated carrier separation.…”