Emerging trends and nanotechnology advances for sustainable biogas production from lignocellulosic waste biomass: A critical review

[Display omitted] •It is possible to generate biogas at a high rate utilizing lignocellulosic (LC) biomass.•Effectiveness of nanotechnology intervention in biogas production from LC biomass has been demonstrated.•LC digestion can be improved by nano-zero-valent metallic nanoparticles.•Adsorption rate and surface-volume ratio enhance the formation of biogas quickly. Biogas production is the most important requirement for substituting fossil fuel in an eco-friendly manner. Though several routes of renewable energy sources are available, biogas generation occupies an irreplaceable position due to huge lignocellulosic biomass availability. Hence, researchers worldwide are attempting on a large scale to develop low-cost and sustainable biogas production for use in transportation, electricity and heat generation. Studies have identified various lignocellulosic resources as raw materials for biogas production. In this context, the nanotechnological intervention and emerging strategies for sustainable biogas production have greater potential to meet the requirements in terms of cost and environmental safety. Biogas generation in oxygen-free digesting processes can be boosted by utilizing customized nanoparticles to dose ions. To maximize biogas generation, it is possible to use unstable nanoparticles, but they can be tailored to provide the ions in a regulated manner. Anaerobic conditions are ideal for nanoparticles dissolution and supply to anaerobic microbes responsible for the organic material breakdown, which is a job that is well-suited to them. However, there exists a large gap in providing up-to-date information on emerging nanotechnology research in biogas generation from enormous uncommitted lignocellulosic resources. To fulfill the lacuna, the present review critically elucidates the existing methods, nanotechnological intervention, emerging and advanced trends in biogas production to benefit society.