Large-scale synthesis and characterization of zeolite-templated carbon for electrochemical application

Abstract

Microporous carbons formed along zeolite pore channels have attracted an attention as catalysts and electrode materials for electrochemical energy conversion- and storage devices. In this thesis, the electrocatalytic performance of N-doped zeolite-templated carbon for oxygen reduction reaction will be addressed. N-doped zeolite-templated carbon exhibited high current capacity and positive onset potential, comparable to those of Pt catalyst due to its large surface area and curved graphene-like structure, which facilitates electron transfer. However, it was difficult to synthesize the zeolite-templated carbon in large-scale with structural regularity and reproducibility. Thereby, systematic studies on the physicochemical properties and electrochemical performance of the carbon was still difficult to be achieved. The major cause of the problems is that carbon precursor is easily deposited on the outer surface of zeolites due to narrow zeolite micropores. In this thesis, catalytic carbonization route within zeolite pores will be addressed to solve this synthetic problem. Calcium ion embedded in zeolite pores catalyzed the carbonization of ethylene, resulting in a pore-selective carbon deposition. This made it possible to obtain high-quality carbon products even in large-scale synthesis using several hundred grams of zeolite. The present synthetic route thus may provide great convenience for further studies on the characterization and electrochemical applications of zeolite-templated carbons.