Recent progress in two dimensional Mxenes for photocatalysis: a critical review

Abstract

Transition metal carbides and nitrides, generally known as MXenes have emerged as an alternative to improve photocatalytic performance in renewable energy and environmental remediation applications because of their high surface area, tunable chemistry, and easily adjustable elemental compositions. MXenes have many interlayer groups, surface group operations, and a flexible layer spacing that makes them ideal catalysts. Over 30 different members of the MXenes family have been explored and successfully utilized as catalysts. Particularly, MXenes have achieved success as a photocatalyst for carbon dioxide reduction, nitrogen fixation, hydrogen evolution, and photochemical degradation. The structure of MXenes and the presence of hydrophilic functional groups on the surface results in excellent photocatalytic hydrogen evolution. In addition, MXenes’ surface defects provide abundant CO2 adsorption sites. Moreover, their highly efficient catalytic oxidation activity is a result of their excellent two-dimensional nanomaterial structure and high-speed electron transport channels. This article, comprehensively discusses the structure, synthesis techniques, photocatalytic applications (i.e., H2 evolution, N2 fixation, CO2 reduction, and degradation of pollutants), and recyclability of MXenes. This review also critically evaluates the MXene-based heterostructure and composites photocatalyst synthesis process and their performance for organic pollutant degradation. Finally, a prospect for further research is presented in environmental and energy sciences.

Versatile MXenes as electrochemical sensors for heavy metal ions and phenolic moiety-containing industrial chemicals: recent development and prospects

“…For further specifics concerning synthetic routes followed to make MXenes, we recommend our readers to other reviews in the literature. [102][103][104] Nonetheless, with the advancements in MXenes, various methods such as hydrothermal, thermal reduction, chemical vapor deposition (CVD), spray drying, and electrochemical techniques are effectively used to generate 2D MXenes devoid of hazardous etchants. The various types of MXenes that are synthesized based on the MAX phase can be referred to in detail from other reports in the literature.…”

Recent Advances in MXenes Based Composites as Photocatalysts: Synthesis, Properties and Photocatalytic Removal of Organic Contaminants from Wastewater

“…[85] In recent years, research has focused on utilizing MXene as a co-catalyst to induce photocatalytic behavior in nanomembranes for water purification, nanostructures for energy conversion, and multifunctional nanocomposites for photocatalytic applications. [86] To enhance the performance of pure components, MXene-semiconductor composites have been developed. These composites help reduce aggregation, increase stability, and provide conductive channels, leading to improved overall performance.…”

“…MXene's unique structural, physical, chemical, and functional properties make it a versatile nanomaterial suitable for various applications across different industries [85] . In recent years, research has focused on utilizing MXene as a co‐catalyst to induce photocatalytic behavior in nanomembranes for water purification, nanostructures for energy conversion, and multifunctional nanocomposites for photocatalytic applications [86] . To enhance the performance of pure components, MXene‐semiconductor composites have been developed.…”

Photocatalytic Activity of TiNbC-Modified TiO2 during Hydrogen Evolution and CO2 Reduction

“…Water splitting with release of H 2 and reduction of CO 2 is based on photocatalysis [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] and electrocatalysis [22][23][24][25][26][27][28][29][30]. But, the greenest technology for hydrogen production and carbon dioxide reduction is the photocatalytic reaction.…”

“…Most works on photocatalytic H 2 production and CO 2 reduction are devoted to model MXene Ti 3 C 2 T x in combination with various semiconductors: TiO 2 , ZnS, CdS, MoS 2 , g-C 3 N 4 , etc. [7][8][9][10][11][12][13][14][15][16]. Several works are devoted to Nb 2 C [17,18].…”