One pot synthesis of klockmannite CuSe nanoparticles for supercapacitors and the electrolyte role.

In this paper, we successfully developed a rapid and straightforward one-pot synthesis method for klockmannite CuSe nanoparticles, demonstrating their potential application in supercapacitors. This synthesis is notably faster and simpler than previously reported methods, requiring no specialized equipment, and can be completed in just 30 min. This process consistently produces 2 nm CuSe nanoparticles with a well-defined hexagonal crystal structure, which is ideal for enhancing supercapacitor electrode performance. In our study, CuSe@SP (Copper selenide supported on SuperP carbon) electrodes exhibited optimal results in TBABF₄ electrolyte, achieving low resistance, high conductivity, and elevated energy density. Furthermore, our findings demonstrate that electrolyte properties-especially ion concentration and the size of negative anions-play a critical role in determining ion transfer rates, with smaller anions significantly enhancing performance. These results not only highlight the potential of our rapid synthesis method but also contribute to a deeper fundamental understanding of electrolyte behavior in advanced supercapacitor systems.