High-entropy spinel oxide: Synthesis and photo-responsivity of Mn0.68Cr0.8Rh0.64Co0.87O4

Recently, there has been extensive research on modulating band structures using MnCr2O4, which has gained significant attention as a photocatalyst. However, due to thermodynamic constraints, conventional modulation of band structures using two compositions poses challenges. Therefore, we utilized a high-entropy approach to easily modulate band structures by forming multi-composition systems (three-composition oxides or higher). The spinel structure of Mn0.68Cr0.8Rh0.64Co0.87O4 produced via electrospinning enabled the fabrication of nano fibers with an average diameter of 160 nm at a calcination temperature of 900 °C, and these nano fibers were crystallized through various analytical instruments. Furthermore, nanofibers calcined at 900 °C exhibited high responsivity and fast rise, decay times under a light source with a wavelength of 635 nm. Thus, with such high reactivity, fast response time, and clear selectivity, Mn0.68Cr0.8Rh0.64Co0.87O4 indicates promising potential as a material for future photo-catalytic research. •This study presents a high-entropy spinel oxide, Mn0.68Cr0.8Rh0.64Co0.87O4, synthesized via electrospinning.•Exhibit high crystallinity, uniform distribution, and thermal stability from increased mixing entropy.•Devices show high responsivity, fast response, and wavelength selectivity, making them ideal for photocatalysis.