Rationally constructed CeO2/Ti3C2Tx-MXene heterostructure for rapid and efficient visible light photocatalytic activity and enhanced supercapacitor performance

Two-dimensional (2D) Ti 3 C 2 T x MXene (MX) benefits from substantial surface area, higher electric conductivity, and abundant surface terminations that can be tightly coupled with other materials, and has found broad application prospects in energy storage and photocatalysis. By this, CeO 2 nanospheres were rationally compounded with MX to obtain nanocomposites (NCs) (CeO 2 /MX1, CeO 2 /MX3, CeO 2 /MX5, and CeO 2 /MX7) via a facile one-step solvothermal method. X-ray diffraction examination discloses the cubic structure of CeO 2, and shrinkage in average crystallite size is noticed up to 5 % of MX. Field emission scanning electron microscopy images show uniform CeO 2 nanospheres decorated on MX 2D matrix, and particle size distribution results are well aligned with crystallite size trends. Optical absorption divulges a progressive red shift in the absorption edge with increasing MX content, demonstrating enhanced light harvesting and effective charge migration through the heterojunction formed at the CeO 2 /MX interface. Electrochemical impedance spectroscopy studies indicate a smaller charge transfer resistance for CeO 2 /MX5, highlighting interfacial conductivity and rapid charge transfer characteristics. Consequently, CeO 2 /MX5 attains a robust photocatalytic tetracycline (TC) degradation surpassing pristine CeO 2 and other CeO 2 /MX NCs. As a supercapacitor electrode, CeO 2 /MX5 delivers a specific capacitance of 522 F g −1 at 0.5 A g −1 and retains 92 % of its initial capacitance after 10000 GCD cycles. This work underscores the effective integration of CeO 2 with 2D MX to achieve a versatile platform for environmental remediation and energy storage applications. • CeO 2 /Ti 3 C 2 nanocomposites were successfully constructed using one-step solvothermal. • CeO 2 /Ti 3 C 2 exhibited superior activity towards tetracycline pollutant. • Hydroxyl radicals play vibrant role in degradation mechanism. • CeO 2 /Ti 3 C 2 delivered a specific capacitance of 522 F/g at 0.5 A/g. • A remarkable cycling stability of 92 % is accomplished after 10000 GCD cycles.