Fluorescent carbon nanomaterials from coal and its derivatives: structure, properties, and applications

Coal is a cheap and sustainable precursor for the preparation of fluorescent carbon nanomaterials (FCNMs). Based on the size and morphology, these nanomaterials are classified as carbon quantum dots (CQDs), carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon nanosheets (CNSs), graphene quantum dots (GQDs), carbon polymer dots (CPDs) etc. The FCNMs have sparked interest because of their distinctive fluorescence, effective catalysis, water solubility, biocompatibility, ease of surface functionalization, cost-effective synthesis, photostability, and other potential benefits for various advanced applications. A substantial percentage of the scientific community has been driven by a strong desire to prepare carbon nanomaterials (CNMs) using environmentally acceptable and low-cost synthesis methods. The precursors used in the preparation of carbon-based nanomaterials are critical to the technology’s future success. Most traditional synthesis procedures use high-cost carbon feedstocks like hydrocarbons and graphite, limiting their commercialization. In this review, coal is used as starting material for the synthesis of FCNMs and is applied in various current fields. Highlights • Coal and its derivatives derived fluorescent carbon nanomaterials are discussed. • Different type of methodology basically top-down and bottom-up for the preparation of fluorescent carbon nanomaterials are described. • The physical and optical properties of fluorescent carbon nanomaterials are discussed. • The origin of fluorescence on coal-based nanomaterials have been discussed. • The multifunctional applications of fluorescent carbon nanomaterials are summarized in detail. • The advantage, challenges and future prospects of fluorescent Carbon Nanomaterials from Coal is discussed. Graphical abstract