Facile Synthesis of High Surface Area Zeolite-Templated Carbon from Sugars and Propylene

Abstract

Zeolite-templated carbons (ZTCs) with high surface areas of ≥3750 m2 g–1 are facilely synthesized from sugars and propylene as carbon sources using NaY zeolite as a template. The zeolite need not be previously dried to remove adsorbed water and can be directly mixed with sugars. The mixture is subject to chemical vapor deposition (CVD) of propylene at 700 °C and subsequent heat treatment at 900 °C, followed by HF etching for zeolite removal. In this study, α-d-glucose, β-d-glucose, d-xylose, d-fructose, and d-sucrose are examined, and a necessary amount of all the sugars per 1 g of the zeolite is reduced to only 0.32 cm3, which corresponds to the total pore volume of the zeolite, for maximizing the surface area and structural regularity of ZTC. Upon heating, adsorbed water desorbs from the zeolite, and the sugars are adsorbed inside the micropores of the zeolite below 300 °C. The adsorbed sugars are carbonized into nanographenes, and the nanographenes are extended and interconnected together via a graphene growth reaction during the CVD. Consequently, the three-dimensionally ordered and interconnected pore structure with a uniform pore size of 1.2 nm is recovered by HF etching, yielding 0.3 g of ZTC per 1 g of the zeolite. The present synthetic method does not require any solvents for adsorption of sugars, and therefore, high surface area ZTCs would become widely and readily available as adsorbents and electrodes for practical applications and fundamental studies.