Enhancing lithium-ion batteries performance via electron-beam irradiation strategies: A case study of graphene aerogels loaded with SnO2 quantum dots

Recent advances in irradiation-mediated synthesis and tailoring of inorganic nanomaterials for photo-/electrocatalysis

Photo-/electrocatalysis serves as a cornerstone in addressing global energy shortages and environmental pollution, where the development of efficient and stable catalysts is essential yet challenging. Despite extensive efforts, it's still a formidable task to develop catalysts with excellent catalytic behaviours, stability, and low cost. Because of its high precision, favorable controllability and repeatability, radiation technology has emerged as a potent and versatile strategy for the synthesis and modification of nanomaterials. Through meticulous control of irradiation parameters, including energy, fluence and ion species, various inorganic photo-/electrocatalysts can be effectively synthesized with tailored properties. It also enables the efficient adjustment of physicochemical characteristics, such as heteroatom-doping, defect generation, heterostructure construction, micro/nanostructure control, and so on, all of which are beneficial for lowering reaction energy barriers and enhancing energy conversion efficiency. This review comprehensively outlines the principles governing radiation effects on inorganic catalysts, followed by an in-depth discussion of recent advancements in irradiation-enhanced catalysts for various photo-/electrocatalytic applications, such as hydrogen and oxygen evolution reactions, oxygen reduction reactions, and photocatalytic applications. Furthermore, the challenges associated with ionizing and non-ionizing radiation are discussed and potential avenues for future development are outlined. By summarizing and articulating these innovative strategies, we aim to inspire further development of sustainable energy and environmental solutions to drive a greener future.

The role of graphene aerogels in rechargeable batteries

Energy storage systems, particularly rechargeable batteries, play a crucial role in establishing a sustainable energy infrastructure. Today, researchers focus on improving battery energy density, cycling stability, and rate performance. This involves enhancing existing materials or creating new ones with advanced properties for cathodes and anodes to achieve peak battery performance. Graphene aerogels (GAs) possess extraordinary attributes, including a hierarchical porous and lightweight structure, high electrical conductivity, and robust mechanical stability. These qualities facilitate the uniform distribution of active sites within electrodes, mitigate volume changes during repeated cycling, and enhance overall conductivity. When integrated into batteries, GAs expedite electron/ion transport, offer exceptional structural stability, and deliver outstanding cycling performance. This review offers a comprehensive survey of the advancements in the preparation, functionalization, and modification of GAs in the context of battery research. It explores their application as electrodes and hosts for the dispersion of active material nanoparticles, resulting in the creation of hybrid electrodes for a wide range of rechargeable batteries including lithium-ion batteries (LIBs), Li-metal-air batteries, sodium-ion batteries (SIBs), zinc-ion batteries (AZIBs) and zinc-air batteries (ZABs), aluminum-ion batteries (AIBs) and aluminum-air batteries and other.

Chemical Surface Adsorption and Trace Detection of Alcohol Gas in Graphene Oxide-Based Acid-Etched SnO2 Aerogels

An acidified SnO₂/rGO aerogel (ASGA) is an attractive contributor in ethanol gas sensing under ultralow concentration because of the sufficient active sites and adsorption pores in SnO₂ and the rGA, respectively. Furthermore, a p-n heterojunction is successfully constructed by the high electron mobility between ASP and rGA to establish a brand-new bandgap of 2.72 eV, where more electrons are released and the surface energy is decreased, to improve the gas sensitivity. The ASGA owns a specific surface area of 256.1 m²/g, far higher than SnO₂ powder (68.7 m²/g), indicating an excellent adsorption performance, so it can acquire more ethanol gas for a redox reaction. For gas-sensing ability, the ASGA exhibits an excellent response of R_a/R_g = 137.4 to 20 ppm of ethanol at the optimum temperature of 210 °C and can reach a response of 1.2 even at the limit detection concentration of 0.25 ppm. After the concentration gradient change test, a nonlinear increase between concentration and sensitivity (S-C curve) is observed, and it indirectly proves the chemical adsorption between ethanol and ASGA, which exhibits charge transfer and improves electron mobility. In addition, a detailed energy band diagram and sensor response diagram jointly depict the gas-sensitive mechanism. Finally, a conversed calculation explains the feasibility of the nonlinear S-C curve from the atomic level, which further verifies the chemical adsorption during the sensing process.

New type of doping effect via metallization of surface reduction in SnO2

The use of conventional doping methods requires consideration of not only the energy connection with the base material but also the limits of the type and doping range of the dopant. The scope of the physico-chemical change must be determined from the properties of the base material, and when this limit is exceeded, a large energy barrier must be formed between the base material and the dopant as in a heterojunction. Thus, starting from a different viewpoint, we introduce a so-called metallization of surface reduction method, which easily overcomes the disadvantages of existing methods while having the effect of doping the base material. Such new synthetic techniques enable sequential energy arrangements–gradients from the surface to the centre of the material–so that free energy transfer effects can be obtained as per the energies in the semiconducting band, eliminating the energy discontinuity of the heterojunction.