Suchergebnisse

Hierarchical 1D carbon structures are attractive due to their mechanical, chemical and electrochemical properties however the synthesis of these materials can be costly and complicated. Here, through the combination of inexpensive acetylacetonate salts of Ni, Co and Fe with a solution of polyacrylonitrile (PAN), self-assembling carbon-metal fabrics (CMFs) containing unique 1D hierarchical structures can be created via easy and low-cost heat treatment without the need for costly catalyst deposition nor a dangerous hydrocarbon atmosphere. Microscopic and spectroscopic measurements show that the CMFs form through the decomposition and exsolution of metal nanoparticle domains which then catalyze the formation of carbon nanotubes through the decomposition by-products of the PAN. These weakly bound nanoparticles form structures similar to trichomes found in plants, with a combination of base-growth, tip-growth and peapod-like structures, where the metal domain exhibits a core(graphitic)-shell(disorder) carbon coating where the thickness is in-line with the metal-carbon binding energy. These CMFs were used as a cathode in a flexible zinc-air battery which exhibited superior performance to pure electrospun carbon fibers, with their metallic nanoparticle domains acting as bifunctional catalysts. This work therefore unlocks a potentially new category of composite metal-carbon fiber based structures for energy storage applications and beyond. ; This work was kindly supported by the EPSRC energy storage for low carbon grids project (EP/K002252/1), the EPSRC Joint UK-India Clean Energy Centre (JUICE) (EP/P003605/1), the EPSRC Multi-Scale Modelling project (EP/S003053/1), and the Innovate UK for Advanced Battery Lifetime Extension (ABLE) project, Soft Science Research Project of Guangdong Province (No. 2017B030301013), Shenzhen Science and Technology Research Grant (ZDSYS201707281026184). Swansea University College of Engineering Advanced Imaging of Materials (AIM) Facility, which was funded by the EPSRC (EP/M028267/1), the European Regional Development Fund through the Welsh Government (80708), and the Ser Solar project via Welsh Government. CG acknowledges The Royal Society of London for an URF.