Multifarious applications of nanoparticles in microalgae for bioenergy generation: State-of-the-art review

Nanoparticles have been discerned to improve the productivity and bioprocessing of microalgae for bioenergy generation. In recent years, the application of nanoparticles has been examined in different aspects of microalgal biofuel production, coupled CO2 bio-fixation, and phycoremediation. The present review discusses various nanoparticles, such as Fe2O3, ZnO, TiO2, that manifest advancement to improve microalgal biofuel production, phycoremediation, and overall plant economics. Different vertices of nanoparticles in the microalgal biofuel system and the possible underlying mechanisms and hypotheses were discussed. The effect of nanoparticles was observed to be dependent on the type, size, and dose of nanoparticles and microalgae species. Cost-benefit analysis revealed nanoparticle usage has the potential to cut down the overall microalgae biofuel production cost by 2.5-4 times. Future perspectives were presented to improve the commercial viability of the nanotechnology-based microalgal biofuel system. Multistage application of nanoparticles is suggested to increase the microalgal biofuel yield and make the overall process efficient, cost-effective and environmentally friendly.