Advanced Ni(II)-Doped -ZIF-8 Nanoscale crystals: A breakthrough in efficient dihydropyrimidine synthesis and catalyst reusability with comprehensive structural characterization

Abstract

Nickel(II) ions (Ni(II)) doped within the zinc-based metal-organic framework ZIF-8 have been demonstrated as highly effective heterogeneous catalysts for the three-component Biginelli condensation reaction. The Ni(10)-ZIF-8 catalyst achieved impressive yields of 96.16 % in ethanol within 100 min, demonstrating excellent selectivity under mild reaction conditions. The incorporation of Ni(II) ions into the ZIF-8 framework was accomplished via a room-temperature synthesis method, with optimal catalytic performance observed at a 10 % Ni doping level. The catalyst was characterized using XRD, SEM, FTIR, and TGA, confirming its high crystallinity and structural stability. Ni(10)-ZIF-8 displayed remarkable reusability, maintaining its catalytic efficiency over five consecutive cycles, with only a 20 % decrease in activity. These findings indicate that Ni(10)-ZIF-8 is not only a highly efficient and sustainable catalyst but also a promising candidate for large-scale applications in green chemistry. Additionally, the study highlights the impact of Ni doping on the catalytic efficiency and the importance of optimizing doping levels for enhanced performance.