Interfacial Electronic Interactions in Graphene Quantum Dot/MXene Systems and Their Consequences for Optical Response

Graphene quantum dot (GQD)/MXene heterostructures represent a rapidly emerging class of 0D/2D hybrid materials with exceptional potential in optoelectronics, sensing, and energy conversion. This comprehensive review systematically addresses the fundamental mechanisms of interfacial electronic reconstruction, including atomic-scale contact geometry, orbital hybridization, Fermi-level equilibration, surface terminations, and ground-state charge redistribution, which collectively define the baseline electronic and chemical architecture of these composites. Nonequilibrium photophysical phenomena, such as exciton generation, ultrafast carrier relaxation, energy transfer, and photoluminescence modulation, are discussed in the context of both electronic structure and chemical environment. Key experimental strategies-including in situ spectroscopy, transient absorption, and time-resolved photoluminescence-are analyzed to link microscopic interactions to macroscopic optical and chemical behavior. The review also integrates synthesis strategies, functionalization approaches, and applications, highlighting how interface engineering enables tunable photothermal conversion, optoelectronic sensing, and energy storage performance. By connecting chemical functionalization with electronic and optical responses, this article establishes a unified framework for understanding ground-state reconstruction and ultrafast optical dynamics in GQD/MXene systems, providing a critical foundation for future interface-centric design of next-generation quantum materials.