Indium Oxides and Related Indium‐based Photocatalysts for Water Treatment: Materials Studied, Photocatalytic Performance, and Special Highlights

Abstract

In2O3 is an emerging material in the photocatalysis research area, with a surge in the number of studies examining indium‐based materials as photocatalysts in recent years. The materials of interest, herein, span the simple indium oxide in different polymorphs and morphologies, ternary, and even quaternary indium oxides, heterostructured systems, all in pure or doped forms. These indium‐based materials offer advantages as photocatalysts compared with the conventional titanium dioxide‐based photocatalysts. Highlights in the literature include reports of the ability of indium oxide to degrade difficult to decompose aqueous organic contaminants while also offering opportunities for visible light activation. These are exciting achievements in this field of research. The unique properties that these materials offer are uncovered, while giving insights as to how indium oxides and related indium‐based materials can be used, in what capacity and the compositional requirements when matched with other semiconductors to achieve high‐performing photocatalysts.

Exploring Solar Energy Solutions for Per‐ and Polyfluoroalkyl Substances Degradation: Advancements and Future Directions in Photocatalytic Processes

“…[36a,60,63] This is attributed to the rapid passivation of the photocatalyst surface due to the incorporation of fluoride ions and nonoptimal alignment of the CBs and VBs. [63,64] As a result, gallium and indium oxides have emerged as promising alternatives in the early part of the past decade, [65] exhibiting faster degradation kinetics and higher defluorination rates than TiO 2 . [60,64,66] This difference has been attributed to the superior sorption properties of PFAS over Ga 2 O 3 and In 2 O 3 .…”

On the CO2 photocatalytic reduction over indium tin oxide (ITO) ultra-thin films in water vapor: Experimental and theoretical study

“…where hν is photon energy, α 0 is a constant, and E g is the band gap [64][65][66][67][68][69][70][71]. The resulting plot is given in Fig.…”

Surface Adsorption and Photoinduced Degradation: A Study of Spinel Ferrite Nanomaterials for Removal of a Model Organic Pollutant from Water

“…In photoinduced contaminant removal processes, the quantity and redox capacity of photogenerated electron–hole pairs are primarily responsible for the contaminant degradation and determine the efficiency of the desired photoassisted reaction . To date, some of the most widely investigated photodriven systems for contaminant removal comprise wide-band-gap metal oxide semiconductors, such as TiO 2 , , Ga 2 O 3 , , and In 2 O 3 , , that are active only under ultraviolet (UV) irradiation. Although UV light contains more energy per photon than visible light, UV light only represents ∼6% of the solar spectrum, whereas visible light makes up to ∼27% of the total available number of photons from incoming solar radiation.…”