Nanostructured Metal Chalcohalide Photocatalysts: Crystal Structures, Synthesis, and Applications

Abstract

Nanocrystals of all-inorganic metal chalco­halides having a combination of chalcogen and halogen anions with appropriate crystal structure and bandgap can be ideal semiconductors in comparison to the well-established multicomponent family of nanostructures. These materials are one of the overlooked semiconductors which could play a paramount role in photocatalysis due to their stability, low-dimensional (1D) structure, and suitable bandgaps with efficient light-responsive nature. Emphasizing these materials, in this Review, recent developments in the design and application of different chalco­halide nanostructures are reported. The initial part is focused on the syntheses and crystal structures of reported chalco­halide materials, followed by an overview of their photocatalytic applications in different aspects. Finally, the successes and challenges associated with the future progress using these materials are discussed. This Review will provide an extended understanding and offer a preferred direction for the innovative design of these materials for environmental and especially energy-based applications.

Advancements in semiconductor quantum dots: expanding frontiers in optoelectronics, analytical sensing, biomedicine, and catalysis

“…The formation of monodisperse nanocrystals with appropriate size was made possible through the use of coordinating ligands and a high reaction temperature. The ability to adjust the semiconductor bandgap via particle size modulation encouraged others to investigate other categories of semiconductor nanocrystals, including chalcohalides, 40 metal halide perovskites, 41 pnictides, 42 and metal chalcogenides, 43 which include ternary semiconductors. The majority of research involving these CQDs, also known as nanocrystals, utilizes the same hot injection method concept as described by Bawendi et al and coworkers.…”

Lead-Free Semiconductors: Phase-Evolution and Superior Stability of Multinary Tin Chalcohalides

“…In the search for alternatives, chalcohalides are quickly gaining attention as semiconductors for multiple applications. − For example, quaternary lead-free Sn 2 PnS 2 I 3 (where Pn = Sb or Bi) chalcohalides display some of the most desirable features of chalcogenide and halide materials, including direct, visible band gaps (<1.6 eV). − Following their original discovery and crystallographic determination, these materials have earned renewed interest in photovoltaics, thermoelectrics, and catalysis applications. − Furthermore, based on preliminary solar devices, tin chalcohalides are believed to exhibit inherently high stability and power conversion efficiency (PCEs), highlighting their potential as valuable materials for energy conversion. , …”

Ultrasmall CsPbBr3 Blue Emissive Perovskite Quantum Dots Using K-Alloyed Cs4PbBr6 Nanocrystals as Precursors

“…There have also been reports on the synthesis of ultrasmall CsPbBr 3 nanocrystals with intermediate size between molecules and QDs, usually named “nanoclusters”. − However, over time, they tend to aggregate. These clusters have mainly been used as “precursors” to prepare CsPbBr 3 nanocrystals of larger sizes or different geometries ,− or even to grow perovskite-based heterostructures. ,− …”