Coal-based carbon quantum dots as plant growth promoters for empowering plant productivity: a sustainable nano-solution

Abstract

A plant growth promoter is a substance or microorganism that enhances the growth and development of plants, providing an agricultural solution. These promoters work by improving nutrient uptake, enhancing root and shoot growth, increasing photosynthesis, and helping plants tolerate stress. This work uses coal-derived carbon quantum dots (CQDs) as plant growth promoters (PGPs) due to their unique physicochemical properties. The PGPs (CQDs) are synthesized using an ultrasonic-assisted chemical oxidation technique with coal as a source material. The structure and morphology of the prepared PGPs were examined using HR-TEM, FT-IR, and UV-vis spectrophotometry. XPS analysis of the CQDs showed the presence of nitrogen and sulfur self-co-doped heteroatoms and carbon and oxygen incorporated through various surface and edge functional groups. Phytological and qRT-PCR analyses of Withania somnifera reveal that coal-derived CQDs significantly enhance plant growth and metabolite content. This study demonstrates the potential of coal-based CQDs as sustainable nanotechnology-based plant growth promoters.