Alkali Metal-Assisted Synthesis of Graphite Carbon Nitride with Tunable Band-Gap for Enhanced Visible-Light-Driven Photocatalytic Performance

Abstract

The development of high-performance semiconductor photocatalysts using solar energy has become a hot topic, which is crucial for a sustainable future. However, construction of a nontoxic and efficient catalyst still remains an enormous challenge. Here, we uncover a simple hydrothermal recalcination method to prepare a novel potassium (K)-doped porous ultrathin g-C 3 N 4 (denoted as KMCN) photocatalyst with efficient catalytic performance, eco-friendly characteristics, and excellent stability. The obtained KMCN nanosheets were applied to the photodegradation of tetracycline (TC) under different reaction condition to simulate practical wastewater treatment. It was found, that the porous structure and K + addition of g-C 3 N 4 enhanced the pore size and specific surface area, and they increased the photoabsorption region and activity sites. The optical properties of KMCN nanosheets were systematically characterized by PL, UV-DRS, etc. The results revealed that the KMCN(0.05) sample possessed a narrowed band gap, lower recombination of photogenerated charges, and higher electron and hole transfer efficiency. Benefiting from these advantages, KMCN(0.05) photocatalysts demonstrated excellent photocatalytic performance for TC degradation (85.13%), which was approximately a 2.88-fold and 1.40-fold increase compared to bare g-C 3 N 4 (29.60%) and porous ultrathin g-C 3 N 4 (60.84%), respectively. These results suggest a reasonable way for the design of economic and high-efficiency photocatalysis.

A comparison study of sodium ion- and potassium ion-modified graphitic carbon nitride for photocatalytic hydrogen evolution

“…Combining the at band potentials and VB values of each sample, the corresponding valence band maximum (VBM) was deduced, and further combining the respective optical bandgap width, the CBM of each sample was also derived. 45,46 Here, GCN is taken as an example to illustrate how its electron band structure was constructed, as shown in Fig. 5(d).…”

Self‐templated Constructing of Heterophase Junction into Hierarchical Porous Structure of Semiconductors for Promoting Photogenerated Charge Separation

“…O 2 − ) were carried out by ESR measurements (Figure ). DMPO/H 2 O and DMPO/CH 3 OH was prepared in the same method as the previous work . The β/α‐Bi 2 O 3 (A) sample was dispersed in DMPO/H 2 O and DMPO/CH 3 OH solutions for detection of .…”

Highly Sensitive and Selective Dopamine Detection Utilizing Nitrogen‐Doped Mesoporous Carbon Prepared by a Molten Glucose‐Assisted Hard‐Template Approach

“…The composition of N‐MC‐MA was further examined by X‐ray photoelectron spectroscopy (XPS) technique. The XPS spectrum of N‐MC‐MA (Figure a) exhibits three peaks at 285.0 eV, 400.7 eV and 532.5 eV for C1s, N1s and O1s, revealing that the sample is consisting of carbon, nitrogen and oxygen elements, which are stemmed from the precursors of glucose and MA. Another peak of F1s is also observed, which is attributed to the adsorption of F − by N‐MC‐MA during the removal of mesoporous silica.…”