Combination of Broad Light-Absorption Cu<sub>9</sub>S<sub>5</sub> with S,C,N-TiO<sub>2</sub>: Assessment of Photocatalytic Performance in Nitrogen Fixation Reaction
Khadijeh Pournemati, Aziz Habibi‐Yangjeh, Alireza Khataee
Abstract
In the field of solar energy storage, photocatalytic ammonia production is a next-generation technology. The rapid recombination of charges and insignificant utilization of the sunlight spectrum are bottlenecks of effective photocatalytic N 2 fixation. The introduction of impurities in the crystal lattice and the development of heterojunctions could effectively segregate carriers and improve the solar-light-harvesting capability, which can boost NH 3 generation. Therefore, in this work, three-element doping by S, C, and N was carried out to rectify the photocatalytic feature of TiO 2, and then it was combined with a broad-light-absorption Cu 9 S 5 semiconductor. The synthesized S,C,N-doped TiO 2 /Cu 9 S 5 nanocomposites with a QD size of almost 7.17 nm exhibited outstanding ability in photocatalytic N 2 reduction, and the generation of NH 3 reached 23 567 μmol L –1 g –1 without sacrificial agents, which was 5.67 and 2.11 folds larger than TiO 2 and Cu 9 S 5, respectively. The promoted performance of the nanocomposite was ascribed to doping three elements and the construction of a Z-scheme system, which attains efficacious separation of carriers and supplies a dedicated path for carrier migration. This research not only supports a novel, sustainable, and facile strategy for the synthesis of S,C,N-TiO 2 /Cu 9 S 5 nanocomposites with inorganic materials and biocompatible characteristics but also provides new insights into the design and construction of TiO 2 -based materials through nonmetal and low-cost three-elemental doping for photocatalytic nitrogen fixation.