Neodymium oxide (Nd2O3) coupled tubular g-C3N4, an efficient dual-function catalyst for photocatalytic hydrogen production and NO removal

Sci Total Environ. 2021 Jun 15:773:145583. doi: 10.1016/j.scitotenv.2021.145583. Epub 2021 Feb 5.

Abstract

Graphitic carbon nitride (g-C3N4) has emerged as a most promising photocatalyst, non-toxicity and low density, but it is plagued by low activity due to the small specific surface area and poor quantum efficiency. Morphological engineering and coupling with other materials to form hybrids have proven to be effective strategies for enabling high photocatalytic performances. Here, neodymium oxide (Nd2O3) coupled tubular g-C3N4 composites had been facilely synthesized by a solvent evaporation and high-temperature calcination method to realize efficient photocatalytic activity of hydrogen production and NO removal. A series of characterizations, such as XRD, ESR, in-situ DRIFTS, etc., were used to analyze the physical and chemical properties of the bifunctional photocatalyst, which demonstrated that the composite material had more active sites and a faster electron transfer rate. The optimal sample (1 wt% Nd2O3/CN-T) had a H2 generation rate of 4355.34 μmol·g-1·h-1, which was 9.46 times than that of original g-C3N4 obtained through heating melamine (CN-M). In addition, the NO removal rate was also 32.32% higher than that of original CN-M. On the basis of the above photocatalytic experimental results and characterizations, a possible mechanism or pathway was proposed and illustrated. This work could provide a feasible strategy to fabricate tubular g-C3N4-based composites with rare earth metal oxides (dual-factor regulation) to simultaneously enhance photocatalytic hydrogen production and NO removal efficiently (double application).

Keywords: Bifunctional photocatalysts; H(2) production; NO removal; Nd(2)O(3); Tubular g-C(3)N(4).