MoS 2 nano‐flowers stacked by ultrathin sheets coupling with oxygen self‐doped porous biochar for efficient photocatalytic N 2 fixation

Research Progress in Composite Materials for Photocatalytic Nitrogen Fixation

Ammonia is an essential component of modern chemical products and the building unit of natural life molecules. The Haber-Bosch (H-B) process is mainly used in the ammonia synthesis process in the industry. In this process, nitrogen and hydrogen react to produce ammonia with metal catalysts under high temperatures and pressure. However, the H-B process consumes a lot of energy and simultaneously emits greenhouse gases. In the "double carbon" effect, to promote the combination of photocatalytic technology and artificial nitrogen fixation, the development of green synthetic reactions has been widely discussed. Using an inexhaustible supply of sunlight as a power source, researchers have used photocatalysts to reduce nitrogen to ammonia, which is energy-dense and easy to store and transport. This process completes the conversion from light energy to chemical energy. At the same time, it achieves zero carbon emissions, reducing energy consumption and environmental pollution in industrial ammonia synthesis from the source. The application of photocatalytic technology in the nitrogen cycle has become one of the research hotspots in the new energy field. This article provides a classification of and an introduction to nitrogen-fixing photocatalysts reported in recent years and prospects the future development trends in this field.

Synthesis of homogeneous honeycomb MoS2 as the anode material for lithium-ion batteries using chemical vapor deposition and a template method

A honeycomb molybdenum disulfide (MoS2) nanomaterial with a special morphology for use in anodes of lithium-ion batteries was synthesized using a template method and chemical vapor deposition.

Interface engineering: Synergism between S-scheme heterojunctions and Mo-O bonds for promote photocatalytic hydrogen evolution

Simple high-temperature calcination and hydrothermal methods were followed to synthesize CeO₂ and Mo-S, respectively. The efficient photocatalytic hydrogen evolution activity exhibited by the composite catalysts can be attributed to the edge active sites in Mo-S. The Mo-O bonds formed between CeO₂ and Mo-S could further accelerate the processes of separation and migration of electrons between the catalyst interfaces. The hybrid catalyst 10%-CeO₂/Mo-S exhibiting the best hydrogen generation ability (4.3 mmol h^-1g^-1) was obtained by optimizing the content of CeO₂ in CeO₂/Mo-S. Analysis of the PL spectral profile and photocurrent response recorded for the system revealed that 10%-COMS exhibited excellent photogenerated carrier separation ability. Analysis of the LSV and EIS curves revealed that 10%-COMS exhibited the optimal hydrogen production potential. The charge migration resistance provided by the systems was lower than the charge migration resistance provided by CeO₂ and Mo-S. The synergism between the S-scheme heterojunctions and the Mo-O bonds helped accelerate the separation and migration of photo-induced carriers at the catalyst interfaces. The introduction of covalent bonds in the S-scheme heterojunctions and the results presented herein can potentially help develop a new method to realize photocatalytic hydrogen evolution.

A review on vertical and lateral heterostructures of semiconducting 2D-MoS2 with other 2D materials: a feasible perspective for energy conversion

Fossil fuels as a double-edged sword are essential to daily life. However, the depletion of fossil fuel reservoirs has increased the search for alternative renewable energy sources to procure a more sustainable society. Accordingly, energy production through water splitting, CO₂ reduction and N₂ reduction via photocatalytic and electrocatalytic pathways is being contemplated as a greener methodology with zero environmental pollution. Owing to their atomic-level thickness, two-dimensional (2D) semiconductor catalysts have triggered the reawakening of interest in the field of energy and environmental applications. Among them, following the unconventional properties of graphene, 2D MoS₂ has been widely investigated due to its outstanding optical and electronic properties. However, the photo/electrocatalytic performance of 2D-MoS₂ is still unsatisfactory due to its low charge carrier density. Recently, the development of 2D/2D heterojunctions has evoked interdisciplinary research fascination in the scientific community, which can mitigate the shortcomings associated with 2D-MoS₂. Following the recent research trends, the present review covers the recent findings and key aspects on the synthetic methods, fundamental properties and practical applications of semiconducting 2D-MoS₂ and its heterostructures with other 2D materials such as g-C₃N₄, graphene, CdS, TiO₂, MXene, black phosphorous, and boron nitride. Besides, this review details the viable application of these materials in the area of hydrogen energy production via the H₂O splitting reaction, N₂ fixation to NH₃ formation and CO₂ reduction to different value-added hydrocarbons and alcohol products through both photocatalysis and electrocatalysis. The crucial role of the interface together with the charge separation principle between two individual 2D structures towards achieving satisfactory activity for various applications is presented. Overall, the current studies provide a snapshot of the recent breakthroughs in the development of various 2D/2D-based catalysts in the field of energy production, delivering opportunities for future research.