A pre-proof paper from the journal Sustainable Materials and Technologies describes current research on the manufacturing processes and performance of MXene-based photocatalysts for pollutant degradation and solar energy harvesting applications.
Study: MXene-based nanocomposites for solar energy harvesting. Image Credit: Fit Ztudio/Shutterstock.com
MXenes are a two-dimensional nanomaterial class with remarkable photocatalytic characteristics. They are potential candidates for a broad range of applications, including energy harvesting systems, optics, and electromagnetic interference shielding devices.
MXene, as a potential photocatalytic compound, allows for rapid photogenerated charge transport, resulting in great accessibility for surface functional groups in solar energy harvesting devices.
What are MXene-based Photocatalysts?
The rapid growth of urban centers, along with the world's rising population, presents a dynamic problem for delivering safe drinking water. Simultaneously, the high pace of industrialization has led to the development of toxic waste, with serious health and environmental repercussions.
MXenes are a recently discovered 2D nanomaterial family composed of transition metal carbides (TMC), transition metal nitrides (TMN), and transition metal carbonitrides (TMCN).
Photocatalysis, a low-cost and robust photo redox technology, has lately shown considerable promise in cleaning water from diverse organic contaminants using carbon dioxide (CO2) and water (H2O) as end products. In this context, MXene-based photocatalysts with a significant photogenerated charge carrier isolation effectiveness and a high specific surface area have been intensively investigated for pollutant degradation.
MXenes are recognized as outstanding photocatalysts as they have been employed to decompose organic and inorganic pollutants due to their remarkable performance, abundant accessibility, eco-friendliness, and good chemical stability.
Production of MXene-based Photocatalysts
The calcination process, along with a hydrothermal oxidation technique, has been extensively used to produce MXene-derivative photocatalysts by in-situ oxidation of MXene substrates. To create multilayer MXenes, a chemical etching method utilizing hydrofluoric acid (HF) has also been utilized.
Etching parameters like immersion time, heat, and particle size can all impact MXene yield and production. The number of terminal groups on the surface of the MXene, which rises as temperature rises, substantially impact the degree of flaking.
Solar Energy Harvesting using MXene-based Photocatalysts
Due to the high pace of industrialization and the rising greenhouse effects, sustainable and renewable energy sources are essential for the survival of human life. Solar energy is a substantial renewable energy source since total annulus solar radiation is 5-6 MJ-m-2 per day, rendering it the world's most accessible renewable energy source.
MXenes offer a wide range of uses as solar energy harvesters, including dye degrading, CO2 reduction, and water electrolysis. MXene-based nanocomposites have exceptional structural qualities such as highly active edges, high chemical stability, wettability, broad surface area, and strong reduction capacity that may be applied in a variety of industrial sectors.
Combining MXenes with semiconductors with the right band position is a viable way to increase photoactivity while increasing optical absorption and promoting charge separation.
MXene Nanocomposites for Carbon Dioxide Reduction
Using carbon dioxide (CO2) as a component for carbon fuel sources is a potential technique for lowering CO2 levels in the environment while providing renewable energy. Photocatalytic CO2 reduction is one possible technology for attaining this goal since it can transform wasted CO2 into carbon compounds and store sporadic renewable energy in their chemical linkages.
MXene nanocomposites can be used to improve the photocatalytic properties of these semiconductors for CO2 relinkage due to their efficiency in increasing photogenerated charge isolation.
Future Perspective and Avenues for Further Research
The physicochemical features of MXene nanocomposites should be determined in future studies. Extensive hypothetical modeling should investigate the interaction between nanostructure, notable catalytic rates, and shape-dependent specificity.
To improve their practical uses, it is also necessary to build superficial techniques for producing Mxene materials. Until now, Mxene etching and abrasion have relied on dangerous chemicals, posing environmental safety concerns.
Reducing environmental hazards and costs associated with producing such resources is an important future goal for expanding the industrial uses of MXene-based photocatalysts.
MXene-based nanohybrids with suitable kinetic reactivity barriers and thermodynamic adsorption energies may be tailor-made to boost photocatalytic activity by combining unique features of different components, paving the way for industrial-scale MXene nanocomposites applications.
Many current investigations are based on theoretical discoveries that lack experimental backing. Filling the experimental and analytical research gap for MXene-based photocatalysts is critical, necessitating cooperation between computation engineers, electrochemists, and material engineers.
Raza, A. et al. (2022). MXene-based nanocomposites for solar energy harvesting. Sustainable Materials and Technologies. Available at: https://www.sciencedirect.com/science/article/pii/S2214993722000768?via%3Dihub