Carbon Dots as Versatile Metal‐Free Carbocatalysts for Organic Transformations

Abstract Nanoparticles with their high surface area to volume ratio, inherent optical and electronic properties substantially different from their bulk counterparts, and the possibility of tuning surface functionality have attracted tremendous attention in the area of catalysis. Carbonaceous nanomaterials have traditionally been used as a support for loading active catalysts to enhance the effective surface area. In recent years, zero‐dimensional carbon dots (CDs) have found tremendous utility in diverse fields such as catalysis, energy storage and conversion, water splitting, sensing, optoelectronics, and others. These multifold applications of CDs emerge from several advantages, such as ease of preparation, high solubility, low toxicity, high chemical stability, tunable optical properties such as absorption and emission, rapid electron transfer properties, etc. In the catalytic area, CDs have emerged as a carbocatalyst for various applications, ranging from environmental remediation, artificial enzymes, organic transformations, photocatalytic activity, etc. In this review, our primary focus has been the application of CDs as a catalyst for a variety of organic transformations, such as chemical catalysis, photocatalysis, and asymmetric synthesis, along with industrial applications such as CO 2 fixation and biodiesel production. The role of surface functionality on CDs and its effect on the catalytic activities have also been described. The advantages of CDs as a replacement for the expensive metal‐based catalysts, leading toward greener and sustainable organic catalysis, and potential future opportunities are also mentioned here.