Tailoring surface and structural properties of composite materials by coupling Pt-decorated graphene oxide and ZIF-8-derived carbon

Abstract

Ultrasonication is used to obtain new nanoporous composites consisting of Pt-decorated graphene oxide (Pt-GO) and zeolitic imidazolate framework (ZIF-8)-derived carbon with improved surface and structural properties as evidenced by high hydrogen uptake of 0.44 mmol/g at 25 °C and 1 bar. At the same conditions, the bare ZIF-8-derived carbon (CZIF-8) and ZIF-8 showed hydrogen uptakes of 0.13 mmol/g and 0.05 mmol/g, respectively. This significant enhancement in hydrogen adsorption on Pt-GO/CZIF-8 is attributed to spillover mechanism. Moreover, adsorption affinity of CZIF-8 toward diverse gases is examined. CZIF-8 adsorbed larger amounts of CH4 (1.8 mmol/g at 20 °C), CO2 (5.7 mmol/g at 0 °C) and H2 (9.9 mmol/g at cryogenic temperature) at 1 bar in comparison to those obtained for parent ZIF-8. This study shows that the ultrasonication-assisted coupling of Pt-GO and MOF-derived carbons can be used for fabrication of composites with tailored surface and structural properties for adsorption, catalytic and photocatalytic applications.