Quantum dots (QDs) represent a well-known class of semiconducting nanomaterials that are roughly spherical, possessing unique electronic properties arising from their size-dependent band gap (band gap engineering), tunable solubility due to surface functionalization, stable fluorescence, and biocompatibility facilitating important diagnostic applications. Among them, carbon nitride exists in different phases, namely α-C3N4, β-C3N4, cubic C3N4, pseudocubic C3N4, and graphitic C3N4 (g-C3N4), although the enhanced thermodynamic stability makes the last one more interesting specifically to be utilized as a supplement of carbon in aforementioned applications. Consequentially, g-C3N4 quantum dots receive special attention since their method of preparation plays a significant role in regulating their electron-rich properties, especially morphological features, toxicity, size distribution, catalytic/electrocatalytic properties, and photostability. This is primarily because g-C3N4 QDs have structural similarity to that of graphite with carbon and nitrogen atoms arranged in a hexagonal lattice and are comprised of tri-s-triazine (heptazine) units connected with planar amino groups, with the inplanar distance of nitride pores at the centre of heptazine units of 7.11 Å and a minor bond distortion can have dramatic consequences. These QDs are environment-friendly and act as effective heterogeneous catalysts for broad chemical reactions, such as water splitting, catalytic oxidation of alkanes and alcohols, photodegradation of pollutants, and NO decomposition and various other applications, including sensing, bio-imaging, photodynamic therapy, and energy conversion. Furthermore, these QDs are important for improving the catalytic converters in fuel cells, supercapacitors, and metal-air batteries. Among these, fuel cells have garnered significant attention for their eco-friendly operation. Fuel cells generate electricity through the electrochemical oxidation of fuels like ethanol, hydrogen, or methanol at the anode. The efficiency of fuel cells hinges on the oxygen reduction reaction (ORR), making the choice of catalyst pivotal. While noble metals like platinum (Pt) have been extensively researched (from Table ) for ORR catalysis, their high cost, limited availability, and susceptibility to degradation pose significant challenges for practical applications. Additionally, Pt-based catalysts face issues such as particle dissolution, surface oxide formation, and aggregation in alkaline electrolytes . In contrast, non-precious transition metals, metal oxides, chalcogenides, carbides, nitrides, phosphides, MXenes and their composites with carbon materials offer promising alternatives with improved stability and reduced fuel crossover effects. However, metal-based electrode materials still exhibit drawbacks such as poor durability in extreme pH environments, relatively high cost, and environmental concerns. Therefore, there is a pressing need to develop stable, metal-free ORR catalysts that are both cost-effective and environmentally benign to realize the full potential of fuel cells. The quest for highperformance catalysts devoid of noble metals remains critical in advancing fuel cell technology.