Regulation of TS-1 zeolite morphology by crystallization modifiers to boost the oxidative reactions

Abstract

TS-1 zeolite is a heterogeneous catalyst renowned for its remarkable catalytic performance in oxidation processes. Thus, tailoring its morphology is crucial for targeted reactions. Herein, we presented a facile and versatile method to regulate the orientation-dependent growth behavior of TS-1 zeolite by utilizing crystal growth modifiers (CGMs). Nanosheet TS-1 zeolites with a short b-axis dimension were synthesized using N,N-dimethylformamide (DMF) as a CGM, while thin-layer assemblies along the c-axis dimension with a hierarchical structure were prepared in the presence of N,N-dimethylacetamide (DMA) or N,N-dimethylpropionamide (DMP) as CGMs. The directional adsorption of different CGMs on specific crystal facets of zeolite was found to be the core reason for modulating the morphology of TS-1. Diverse TS-1 morphologies were suitable for different oxidation reactions: nanosheets enhanced selectivity in 1-hexene epoxidation, while thin-layer assemblies showed excellent activity and stability in dibenzothiophene oxidative desulfurization. This work offers further insights into customizing zeolite properties and optimizing their catalytic performance.