Publication date: 15th December 2025
The transition to sustainable energy is urgent, and, in this context, metal-air batteries arise as a promising technology for achieving high efficiency and zero emissions. However, these systems relay on the oxygen reactions, which necessitate the use of efficient electrocatalysts due to its slow kinetics.[1-3] Although Pt-based catalysts are benchmark materials for this application, they suffer from high cost and poor durability, driving the need for earth-abundant, stable alternatives.[4] On the other hand, air cathodes require effective operation in a solid–liquid–gas environment, where gas diffusion, electrolyte transport, and electron conduction must be balanced to ensure optimal performance. Structural degradation of the carbon matrix during cycling can weaken the interfacial contact, leading to performance decay.[5] Thus, beyond intrinsic activity, it is essential to build robust, hierarchically porous carbon frameworks with high surface area. Mesopores enhance electrolyte infiltration, expand the active interface, and reduce transport resistance, while multi-scale porosity helps relieve mechanical stress over cycling.[6] Interconnected micro/mesopores around 4–6 nm are particularly desirable for durable oxygen catalysis.
In this work, the use of Co-doped ZIF-8 as the precursor is proposed. Its N-rich imidazolate ligands facilitate the formation of Co–Nx sites embedded in a conductive carbon matrix after pyrolysis. The framework also ensures molecular-level metal dispersion and allows easy Co incorporation, creating numerous accessible catalytic sites. Moreover, Zn volatilization during pyrolysis generates a self-templating effect, producing extra porosity and improves site exposure. Compared with hard-template or multi-step methods, Co-ZIF-8 routes are simpler, more economical, and sustainable, yet still deliver high surface area and optimized pore structure. By leveraging in-situ assembly of Co/ZIF-8 on a biomass-derived substrate (e.g., CNC) followed by pyrolysis and post-treatment, it is possible to obtain hierarchical carbons with pronounced mesoporosity, rapid transport pathways, and good oxygen catalysis performance in alkaline electrolyte, approaching Pt/C while maintaining good cycling stability.
The authors would like to acknowledge the financial support provided by Ministerio de Ciencia y Innovacion (MCIIN), the Agencia Estatal de Investigacion (AEI) and the European Regional Development Fund (FEDER) (grants PID2024-157199OB-C21) and the Severo Ochoa Centres of Excellence programme, Grant CEX2021–001214-S, for this research activities. S.Y.Chen also acknowledges his scholarship (No. 202308610050) under China Scholarship Council.
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.