On a Composite Obtained by Thermolysis of Cu-Doped Glycine

Abstract

Metal-doped carbonaceous materials have garnered significant attention in recent years due to their versatile applications in various fields, including catalysis, energy storage, environmental remediation, electronics, and sensors, as well as reinforcement. This study investigates the synthesis and characterization of a composite material featuring a carbonaceous matrix doped with copper, focusing on the thermolysis of glycine as a precursor. The synthesis methodology involved utilizing glycine and copper acetate monohydrate in varying ratios, with the mixture subjected to heating in ceramic crucibles at temperatures ranging from 450 to 550 °C, with pyrolysis yields over the 5 to 39% interval. The pristine and Cu-doped samples obtained at 500 °C underwent characterization using a diverse array of techniques, including scanning and transmission electron microscopies, multi-elemental analysis by energy dispersive X-ray spectroscopy, CHNS elemental analysis, X-ray photoelectron spectroscopy, X-ray powder diffraction, infrared and Raman spectroscopies, ultraviolet-visible spectroscopy, and terahertz time-domain spectroscopy, along with conductivity measurements. Under optimized conditions, copper (at 6.5%) was present primarily in the free metallic form, accompanied by traces of tenorite (CuO) and cuprite (Cu2O). The carbonaceous matrix exhibited a 6:1 ratio of graphitic carbon to a carbon-nitrogen compound with the formula C2H2N2O2, such as isomers of diazetidinedione, according to multi-elemental analysis results. Conductivity measurements disclosed a significant increase in conductivity compared to the product of glycine thermolysis, showcasing the enhanced electrical properties of the new composite. Additionally, terahertz measurements showed the potential of the material as a broadband absorber for the fabrication of terahertz devices and provided compelling evidence of a significant improvement in radiation absorption upon copper doping. In conclusion, this research sheds light on the promising properties of copper-doped carbonaceous composites obtained by glycine pyrolysis, offering insights into their potential applications in emerging technological domains.