Synthesis of 3-Dimensional Resorcinol-Urea-Formaldehyde Carbon xerogel electrode and its application in benthic microbial fuel cell

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

In energy applications, the use of materials with hierarchical porous structures and large surface areas is essential for efficient charge storage. These structures facilitate rapid electron and ion transport, resulting in high power density and quick charge/discharge capabilities. Carbon-based materials are extensively utilized due to their tunable properties, including pore sizes ranging from ultra- to macropores and surface polarity. Incorporating heteroatoms such as nitrogen, oxygen, sulfur, phosphorus, and boron modifies the carbon structure, enhancing electrocatalytic properties and overall performance. A hierarchical pore structure is necessary for optimal performance, as it ensures efficient access to the material's core. The microstructure of carbon materials significantly impacts energy storage, with factors like polyaromatic condensation, crystallite structure, and interlayer distance playing crucial roles. Carbon aerogels, derived from the carbonization of organic gels, feature a sponge-like structure with large surface area and high porosity, making them suitable for energy storage. Their open pore structure supports fast ion transfer, leading to high energy and power densities. Challenges include maintaining mechanical or structural integrity, multifunctional features, and scalability. This review provides an overview of the current progress in carbon-based aerogels for energy applications, discussing their properties, development strategies, and limitations, and offering significant guidance for future research requirements.

Exploiting a High-Performance "Double-Carbon" Structure Co9S8/GN Bifunctional Catalysts for Rechargeable Zn-Air Batteries

Rational synthesis of bifunctional electrocatalysts with high performance and strong durability is highly demanded rechargeable metal-air battery. In this work, ZIF-derived Co₉S₈/C coated with conductive graphene nanosheet (Co₉S₈/GN) was synthesized by a simple solvothermal method and formed a stable double-carbon structure. As expected, the prepared Co₉S₈/GN catalyst exhibits a high catalytic activity (ΔE: 0.88 V) and long-term durability toward both oxygen reduction reaction and oxygen evolution reaction (ORR and OER), which is even superior to the Pt/C + Ir/C mixture (0.91 V). In addition, the Zn-air battery with the Co₉S₈/GN catalyst showed higher power density (186 mW cm^-2) and more stable charge-discharge cycling performances (2000 cycles) than the Pt/C + Ir/C (118 mW cm^-2). Based on these analysis results, the favorable catalytic performance of ORR/OER should be illustrated by the following reasons: (i) large specific surface area and unique mesoporous structure, providing abundant active sites; (ii) good conductivity, accelerating the electrons transfer; and (iii) the unique stable "double-carbon" structures (metal-S-C-C), preventing the agglomeration of metal sulfide, building new quick transfer pathway, and forming the strong electron coupling ability and synergistic effect.