Pd/Ti3C2 nanohybrids as heterogeneous catalyst for efficient catalytic reduction of hazardous water pollutants at ambient conditions

Nitrophenols are toxic priority pollutants that pose significant environmental and health risks, necessitating efficient strategies for their removal from wastewater. Catalytic transfer hydrogenation (CTH) using formic acid (FA) as a green hydrogen source represents a promising approach. This study reports the development of MXene (Ti 3 C 2 T x )-supported palladium nanoparticle catalysts (Pd/Ti 3 C 2 T x ) for the efficient reduction of 4-nitrophenol (4-NP) under ambient conditions. The catalysts, with nominal Pd loadings of 2%, 3%, and 5% (designated as TP2, TP3, and TP5), were synthesized by immobilizing Pd nanoparticles onto MXene, which was derived from the Ti 3 AlC 2 MAX phase via HF etching. Comprehensive characterization using XRD, FE-SEM, TEM, BET, EDX, and ICP-OES confirmed the successful etching of Al, the layered structure of MXene, and the dispersion of Pd nanoparticles with an average size of ~ 8 nm. The catalytic performance was evaluated in the CTH of 4-NP using a formic acid/sodium formate system. The reaction kinetics followed a pseudo-first-order model. The apparent rate constant (k app ) exhibited a direct correlation with Pd loading, with TP5 demonstrating the highest activity (k app = 0.1072 min − 1 under optimal conditions). Optimization studies revealed that a 0.4:0.2 molar ratio of FA to sodium formate and a catalyst concentration of 3 mg mL − 1 were optimal. Spectroscopic characterization (UV‑Vis, FTIR, NMR) confirmed the formation of 4‑hydroxyphenylformamide, with no trace of 4‑aminophenol indicating that FA acts as both a hydrogen donor and a formylating agent. This work underscores the potential of MXene/Pd nanocomposites as highly active and stable catalysts for the remediation of nitrophenol-contaminated water, offering valuable insights for future industrial applications.