MXene-based gold nanoparticle catalyst with high activity and stability for 4-nitrophenol reduction

Catalytic reduction is considered an effective method for converting organic compounds. However, a lack of efficient catalysts has hindered its practical application. Herein, the cationic poly(diallyldimethylammonium chloride) (PDDA) was used as a stabilizer to synthesize a novel MXene-supported gold nanoparticles composite by electrostatic interaction and self-reduction methods. As a stabilizer bridging transition metal carbides (MXene, Ti3C2Tx) and gold nanoparticles (AuNPs), the PDDA polymer provided rich binding sites for AuNPs immobilization, resulting in uniform distribution of AuNPs on MXene nanosheet and efficient control over their particle size. The synergistic effects of the composite catalyst improved its catalytic activity towards 4-nitrophenol (4-NP) reduction, and the normalized rate constant (K) was high up to 2.65 x 10-2 s � 1. Notably, the composite catalyst also showed high stability due to the protection of PDDA, and the conversion efficiency for 4-NP was high up to 94.85% after five recycles. Our findings presented here not only are potential for catalytic applications, but also provide a foundation for the development of efficient MXene-based catalysts.