ArticleBMC chemistry2026
Synthesis of carbon quantum dots using unutilized low-grade lignite coal.
Article in BMC chemistry, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
1 citing paper in PubMed.
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Authors and funding
6 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The large deposits of unutilized coal in Nigeria present both environmental and economic challenges, including disposal issues and underutilization of a potentially valuable resource. A resource recovery approach, such as converting low-grade coal into high-value products, can offer a sustainable solution with industrial scalability and innovation in nanomaterial synthesis. In this study, carbon quantum dots (CQDs) were synthesized via a one-step oxidation process using lignite coal from Enugu, Nigeria. Elemental analyses (EDX and XPS) confirmed that the CQDs consist of over 90% carbon, containing dopants of sulfur, silicon, nitrogen, and oxygen. These CQDs exhibited direct and indirect allowed band gaps of 2.61 and 2.68 eV, respectively. The produced CQDs exhibited redshifted fluorescence emission spectra at various excitation wavelengths, and an ultraviolet-visible (UV-Vis) absorption maximum around 400 nm. XRD analysis revealed a predominantly amorphous structure (68%) and a crystallite size of 0.650 nm. Structural analyses highlighted quantum confinement effects and significant lattice imperfections, including average microstrain ≈ 0.2. Nitrogen adsorption studies indicated microporous and mesoporous structures with DFT surface area of 52 m
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