Sonochemical synthesis of HKUST-1-based CuO decorated with Pt nanoparticles for formaldehyde gas-sensor applications

This paper proposes a facile and simple method to synthesize composites of copper(II) oxide (CuO) and platinum nanoparticles (N NPs) without altering the original morphology of CuO. The porous CuO derived from metal-organic frameworks of copper benzene-1,3,5-tricarboxylate (HKUST-1, Basolite (R) C 300) was decorated with N NPs of 1-2 nm diameters through a sonochemical synthetic route, and the gas-sensing properties of the CuO decorated with N NPs were investigated. Compared to CuO-based gas sensors, gas sensors based on CuO decorated with 0.06 wt% N NPs showed lower optimal operating temperature and advanced gas response over 82% in detecting formaldehyde gas from 100-1500 ppb at 225 degrees C. Here, the N NPs decorated CuO gas sensors showed improved sensing performances to formaldehyde (2.64 at 100 ppb at the operating temperature of 225 degrees C), and the proposed method could be expandable to the decoration of other noble metals, such as palladium (Pd) and gold (Au). Thus, this method would be very useful for the formation of sensor arrays in a simple and facile manner, for various applications of statistic pattern analysis, using principal component analysis (PCA), neural network or machine learning.