Converting rice husk biomass into value-added materials for low-carbon economies: Current progress and prospect toward more sustainable practices
Ngoc N. Nguyen, Anh V. Nguyen, Muxina Konarova
Abstract
The abundant rice husk agrowaste possesses a silicon-rich composition in the form of natural biogenic silicon/carbon blend. This unique property of rice husk (RH) enables the preparation of nanohybrid materials with particular properties which are otherwise difficult to achieve via synthetic means. RH-derived nanostructured materials show promising applications in low-carbon economies such as heterogeneous catalysts for hydrogen generation and decarbonisation, battery anodes, supercapacitors, drug carriers, quantum dots, solar grade silicon, and adsorbents. Here, we discuss the latest advances in converting RH into such value-added materials and highlight the drawbacks of the current methods which are unsustainable due to high consumptions of energy and harsh chemicals. We elaborate a distinctive forward-looking perspective on the transition toward more sustainable practices via enzymatic processing, microwave- or ultrasound-assisted conversion, and the use of eco-friendly chemicals, for more energy- and cost-efficient productions of RH-derived products. Insights provided by this paper promote the progress in agrowaste recycling toward a circular decarbonised world. • Abundant rice husk (RH) biomas is a precious resource for synthesis of energy materials. • Naturally-blended biogenic silicon/carbon in RH is a unqiue advantage. • RH-derived materials show promising applications in energy and environment sectors. • Current RH processing is unsustainable due to high consumptions of energy and harsh reagents. • Future sustainable practices utilise enzymes, microwave, ultrasound and eco-friendly reagents.