Transformation study and characterization of Cu-BTC MOF-derived nanoporous copper oxide.

Abstract

This study provides a systematic and comprehensive investigation of the transformation process of copper-based metal-organic frameworks (Cu-BTC MOFs) into nanoporous copper oxides (P-CuO_x) through controlled calcination. While calcination is a well-established method for producing MOF-derived oxides, previous studies have primarily focused on their applications. Most of them often lack detailed exploration of the transformation process and decomposition mechanisms though it is crucial for achieving tunability in MOF-derived structures. Our study addresses this gap by offering valuable insights that can guide the production of various MOF-derived oxides with tunable structural and functional properties. In this report, we have meticulously analysed the combined effects of calcination parameters, including temperature (250-500 °C), heating rate (0.5-10 °C min^-1), and duration (1 and 2 hours) on the phase transformation, morphological features, and optical properties of Cu-BTC during its transformation to P-CuO_x. Results revealed that fine adjustments to these calcination parameters allow precise control over phase purity, surface area, and porosity, achieving a high surface area of 113 m² g^-1 for derived P-CuO. Furthermore, the P-CuO_x materials exhibited strong visible-light absorption, highlighting their potential for solar energy harvesting applications. This approach opens opportunities for designing advanced materials with customized performance characteristics. The findings have broad applicability and enable the research community to fully exploit MOF-derived oxides for designing advanced materials with customized properties for diverse applications, including energy, sensing, and biomedical.