Structure-Dependent Surface Molecule-Modified Semiconductor Photocatalysts: Recent Progress and Future Challenges

Abstract

For the photocatalytic process, the development of efficient photocatalysts is a key and important issue. In recent progress, grafting molecules on the surface of semiconductors via coordination chemistry has received increasing attention owing to its unique advantages. The molecules in molecule-modified semiconductor photocatalysts exhibit three main specific functions, that is, enhancing the light absorption capacity, accelerating charges transfer and improving the surface reaction kinetics; and the regulable structure of molecule has an essential impact on the above functions. In this review, a general introduction to the photocatalysis phenomenon, evaluation and construction of photocatalysts is given first. Then, the type of molecules is introduced; the case studies in typical applications of photocatalytic hydrogen evolution, pollutants removal and carbon dioxide reduction are addressed, focusing on the fabrication, photocatalytic performance and structure−function relationship. In the last section, the underlying challenges and opportunities in future research for molecule-modified photocatalysts are addressed and concluded.

Integration of Electrochemical Oxidation and Photocatalytic Degradation with Robust Synergistic Effect for Efficient Wastewater Treatment

“…Incident light, with an appropriate wavelength, excites the photocatalyst to initiate a series of chemical reactions. 3 Generally, the photocatalysts remain stable when exposed to irradiation, avoiding photolysis. This high stability allows them to sustain multiple cycles of photocatalysis without a decline in activity.…”

Covalent Organic Framework/g-C3N4 van der Waals Heterojunction toward H2 Production

“…The construction of heterostructures is of great interest to researchers with regard to single-component catalysts. On the one hand, the heterostructure could couple the advantages of each component (enhanced optical absorption capability, higher reaction rates, and so on) and endow the photocatalysts with some additional features due to the synergistic effects; on the other hand, a built-in electric field will be formed due to the difference of the band-edge position between the two semiconductors, which will then drive e – and h + to transfer into reverse directions, resulting in a spatial separation of photoinduced e – and h + on different parts of the composite. − Especially, the 2D/2D heterojunctions possess greater charge mobility due to the higher face-to-face contact area and shorter transfer distance caused by the atomically well-defined ultrathin interface …”

Gradient Alloyed Quantum Dots for Photocatalytic Lignin Valorization via Proton Coupled Electron Transfer

“…Widness et al 39 used the Auger process to make CdS capable of catalyzing difficult reduction reactions like reductive ring opening of cyclopropane−carboxylic acid derivatives. Liu et al 38 investigated the performance of surface molecules on semiconductor catalysts for biomass conversion.…”