Comprehensive Insights and Advancements in Gel Catalysts for Electrochemical Energy Conversion

Abstract

Continuous worldwide demands for more clean energy urge researchers and engineers to seek various energy applications, including electrocatalytic processes. Traditional energy-active materials, when combined with conducting materials and non-active polymeric materials, inadvertently leading to reduced interaction between their active and conducting components. This results in a drop in active catalytic sites, sluggish kinetics, and compromised mass and electronic transport properties. Furthermore, interaction between these materials could increase degradation products, impeding the efficiency of the catalytic process. Gels appears to be promising candidates to solve these challenges due to their larger specific surface area, three-dimensional hierarchical accommodative porous frameworks for active particles, self-catalytic properties, tunable electronic and electrochemical properties, as well as their inherent stability and cost-effectiveness. This review delves into the strategic design of catalytic gel materials, focusing on their potential in advanced energy conversion and storage technologies. Specific attention is given to catalytic gel material design strategies, exploring fundamental catalytic approaches for energy conversion processes such as the CO2 reduction reaction (CO2RR), oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and more. This comprehensive review not only addresses current developments but also outlines future research strategies and challenges in the field. Moreover, it provides guidance on overcoming these challenges, ensuring a holistic understanding of catalytic gel materials and their role in advancing energy conversion and storage technologies.

Conductive Gels for Energy Storage, Conversion, and Generation: Materials Design Strategies, Properties, and Applications

“…Aerogel formation involves the replacement of liquid with gas without collapsing the polymer networks. This process occurs in two distinct steps: gel formation and subsequent drying (Figure 3) [42]. The drying phase presents a significant challenge, as the surface tension of the solvent within the gel can promote the destruction of the gel structure during solvent evaporation.…”

Potential of Carbon Aerogels in Energy: Design, Characteristics, and Applications

“…Moreover, low-density gels exhibit low resistance to surface tensions, potentially causing integration issues within the skeleton. Despite its superiority in minimizing the shrinkage of meso–/macro–pores, the industrial–scale implementation of this method remains highly costly [ 33 , 34 , 35 ].…”

“…within the skeleton. Despite its superiority in minimizing the shrinkage of meso-/macropores, the industrial-scale implementation of this method remains highly costly [33][34][35]. Microwave drying operates under electromagnetic fields through dipole reactions among dielectric molecules.…”

Materials Design and Development of Photocatalytic NOx Removal Technology

“…Additionally, morphology engineering plays a pivotal role, ensuring high mass transport and maximizing the exposed surface area of the catalyst. To enhance the light-harvesting capacity within the visible region, molecular-level engineering of the materials is conducted through strain engineering, defect engineering, metal decoration, and innovative heterojunction formation [21,22]. These approaches mechanistically improve charge separation while simultaneously adjusting the band structure of the catalyst, thus enhancing its overall performance.…”