Madhulika Dutta, Sumit Kumar, Rajasekhar Bhimireddi, Madhulata Shukla, Anil Koparkar, Krishna Prasad Sharma, Rajender S. Varma, Ravi Kr. Gupta, Rajeev Kumar, Laxman Singh
Micro- and nano-plastics (M/NPs) are omnipresent in oceanic and terrestrial ecosystems, posing massive environmental and human health risks. The overview of their types, life cycle, and laser spectroscopic detection is followed by a critical evaluation of degradation pathways, including photocatalytic, thermal, mechanical, microbial, catalytic, ozone-induced, and laser-assisted pathways. Recent advances on semiconducting photocatalysts-metal oxides, metal chalcogenides, and carbon-based nanomaterials-are discussed with particular emphasis on the structural modification for enhanced activity. Green synthesis routes via plant extract, bacteria, algae, and fungi are shown as sustainable approaches for large-scale remediation of M/NPs. Mechanistic insights into light–matter interactions as well as degradation processes are offered, emphasizing the necessity for cost-effective and eco-friendly alternatives to mitigate M/NP pollution.