UC Riverside

Crystalline porous metal chalcogenides have attracted extensive attentions due to its integration of highly porous structure and semiconducting property. Our research group has made great contributions to the development of chalcogenide molecular clusters with their three-dimensional (3D) structures.

While most of the previous efforts are devoted to developing new crystal structures, research on the functionalization of this kind of materials are somewhat ignored. As built from well-defined nanoclusters, the metal chalcogenide materials can build a bridge between the molecular clusters and the resulting three-dimensional structures. By controlling the chemical composition on the nano-sized clusters or tuning the host-guest chemistry in the frameworks, custom-design functionalization can be realized.

Among them, zeolitic porous chalcogenide, possessing the zeotype structures, stands out due to its high thermal and chemical stability, high porosity, flexible chemical composition and accessible cation-exchange property.

In the first part of this work, trimetallic zeolitic porous chalcogenides with tunable chemical compositions were successfully developed. The valence and ionic diameter of the metal cations, were found as the key factors affecting the self-assembling process. Through tuning the chemical composition with different atomic ratio in the molecular clusters, tunable band gaps can be successfully realized. The studies here build a bridge between the molecular semiconducting clusters and the resulting frameworks, providing a systematic investigation on the structural retention and alternation of zeolitic porous chalcogenides. The as-synthesized frameworks exhibit the selective photocatalytic properties. By integration of high porosity, semiconductivity and cation-exchange property, a promising platform is well demonstrated for the development of selective photocatalytic materials.

In the second part, functionalization of zeolitic porous chalcogenide through cation exchange are well demonstrated. Because of their unique integration of the chalcogen-soft surface, high porosity, all-inorganic crystalline framework, and the tunable charge-to-volume ratio of exchangeable cations, a special family of porous chalcogenides for CO2 adsorption in terms of extraordinarily high selectivity, large uptake capacity, and robust structure is developed. Moreover, zeolitic porous chalcogenide can serve as the dual hard template for fabricating the heteroatom doped carbon materials for electrocatalytic reactions with high efficiency.