Mmabatho Martina Matlaila
Department of Chemistry, Sefako Makgatho Health Science University, P.O. Box 94,
Medunsa 0204, South Africa
Nduduzo Lungisani Khumalo
Department of Chemistry, University of Zululand, KwaDlangezwa 3886, South Africa
Samson Masulubanye Mohomane
Department of Chemistry, University of Zululand, KwaDlangezwa 3886, South Africa
Cebisa Linganizo-Dziike
Department of Chemistry, Sefako Makgatho Health Science University, P.O. Box 94,
Medunsa 0204, South Africa
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa
Institute for Catalysis & Energy Solutions (ICES), Florida Campus, University of South Africa, Johannesburg 1709, South Africa
Thembinkosi Donald Malevu
Department of Physical and Chemical Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
Tshwafo Elias Motaung
Department of Chemistry, Sefako Makgatho Health Science University, P.O. Box 94,
Medunsa 0204, South Africa
Synthetic dyes, particularly azo dyes, pose significant environmental and health risks due to their persistence, toxicity, and potential carcinogenicity. Zinc oxide (ZnO) is a promising photocatalyst for wastewater remediation, but its wide bandgap and rapid charge recombination limit its practical efficacy. Furthermore, conventional doping methods often rely on hazardous chemical precursors, undermining the sustainability of the overall approach. This review introduces a novel and sustainable paradigm: the utilization of biomass-derived precursors as green reagents for the in-situ synthesis and simultaneous phosphorus-nitrogen (P-N) co-doping of ZnO nanoparticles. We critically analyze how the intrinsic biochemical composition of biomass, rich in P, N, and other heteroatoms, facilitates this one-pot, eco-friendly functionalization. This integrated strategy merges the performance enhancement offered by advanced co-doping, such as extended visible-light absorption and suppressed charge recombination, with the core principles of green chemistry and circular economy. It offers a dual benefit: creating highly effective photocatalysts for the degradation of persistent pollutants and valorizing abundant agricultural or biological waste streams. Our comprehensive evaluation goes beyond description to critically assess the underlying mechanisms, comparative efficacy, scalability challenges, and future research directions of this emerging field. This review underscores the unique contribution of biomass-mediated synthesis to advancing sustainable nanotechnology for environmental applications.
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Copyright © 2025 Mmabatho Martina Matlaila, Nduduzo Lungisani Khumalo, Samson Masulubanye Mohomane, Cebisa Linganizo-Dziike, Thembinkosi Donald Malevu, Tshwafo Elias Motaung
This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.
