Biomass-derived Carbon Quantum Dots – A Review. Part 1: Preparation and Characterization

The preparation of nanostructured carbon materials from chosen biomass through hydrothermal carbonization and pyrolysis processes by optimizing the reaction conditions is one of the bases for applying the product in certain of the development activities. The finished product more or less reflects the raw material and the way of preparation. Among the many products, carbon quantum dots (CQDs) have gained importance due to their bolstered characteristics and facile preparation. CQDs are zero-dimensional (0D) nanomaterials which attracted attention in the recent past due to their excellent water solubility, unique optical properties, good electrical conductivity, eco-friendliness, and biocompatibility. Small-sized CQDs offer high surface area per unit volume, strong tunable fluorescence, photo-luminescent emissions, and semiconducting properties. In this paper, identification of ideal raw materials, process parameters being followed in the preparation of CQDs through hydrothermal carbonization and pyrolysis techniques, and the properties of the resultant CQDs commensurate with the nature of process are reviewed.