Recently, in response to the challenges related to energy development and environmental issues, extensive efforts are being made towards the development of supercapacitors based on green and sustainable resources. Aerogel electrodes offer high energy/power autonomy, fast charge-discharge rates, and long charge/discharge cycles over composite film electrodes due to their unique structure, ultra-lightness, high porosity, and large specific surface area. Nanocellulose (NC), a sustainable nanomaterial, has gained popularity as a supercapacitor electrode material owing to its remarkable properties such as biodegradability, tunable surface chemistry, ability to develop 3D aerogel structures, etc. This comprehensive review summarizes the research progress on developing NC-based aerogels for supercapacitor applications. First, the fundamentals of NC extraction from cellulose sources and aerogel processing routes are discussed. An attempt is made to correlate the electrochemical performance of NC-based electrodes with their aerogel structures. Finally, challenges and future prospects for the advancement of NC-based aerogels are addressed.
Key Laboratory of Catalytic Conversion and Clean Energy in Universities of Shandong Province, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165, P. R. China.
Nanostructured Faradaic materials show extraordinary promise for capacitive deionization (CDI) toward the relief of global freshwater scarcity. But at present, there exist at least two shortages for the development of CDI electrode materials. In laboratory studies, evaluating their desalination performance is usually based on low mass loadings (<1 mg cm), which is far behind the practical demand for fabricating high-mass-loading CDI electrodes or devices.
Carbon nanostructures are highly promising materials for applications in a variety of different fields. Besides their interesting performances, the possibility to synthesize them from biowaste makes them an eco-friendly resource widely exploitable within a circular economy context. The present work deals with the green, one-pot synthesis of graphene quantum dots (GQDs) from carbon aerogels (CAs) derived from rice husk (RH).
The hydrogen evolution reaction (HER) efficiency is highly dependent on the electrocatalysts microstructure and the macrostructure of the electrodes. Herein, the graphene aerogel microspheres loaded with well-dispersed ultrafine Ni/Co nanoparticles catalyst is prepared through electro-spraying, in-situ crosslinking, freeze-drying, and pyrolysis, and then is utilized to print the HER electrode via direct ink writing (DIW). The obtained graphene-based aerogel microspheres possess peculiar cabbage-like mesoporous structures which allow ready access of reaction species to active sites, optimal mass transfer, and proton diffusion within the microspheres.
Iridium (Ir) is the most active and durable anode catalyst for the oxygen evolution reaction (OER) for proton exchange membrane water electrolyzers (PEMWEs). However, their large-scale applications are hindered by high costs and scarcity of Ir. Lowering Ir loadings below 1.
Background: Safe implementation and translation of FLASH radiotherapy to the clinic requirehs development of beam monitoring devices capable of high temporal resolution with wide dynamic ranges. Ideal detectors should be able to monitor LINAC pulses, withstand high doses and dose rates, and provide information about the beam output, energy/range, and profile.
Purpose: Two novel detectors have been designed and tested for ultra-high dose-rate (UHDR) monitoring: a multilayer nano-structured 3-layer high-energy-current (HEC3) detector, and a segmented large area, 4-section flat (S4) detector with the goal of exploring their properties for a future combined design.
