High-entropy oxide for enhanced supercapacitors and precise electrochemical detection of dopamine at nanomolar levels

The ability to synthesize multi-metal elements into a single-component material at the nanoscale, known as high entropy oxide (HEO) is earning great attention, especially in the field of electrocatalysis. However, the present methods for the synthesis of HEO often involve non-noble, noble, or refractory elements, which require complicated synthesis methods, making the control of shape and size highly challenging. In this regard, a class of six dissimilar elements (Co, Ni, Mn, Mo, V and Zn) with combination of non-noble and refractory elements has been formed a new type of (Co 0.5 Ni 0.5 Mn 0.5 Mo 0.5 V 0.5 Zn 0.5 )O based HEO. The multi-element interaction and carbonization network enhance ion conductivity, boosting specific capacitance to 698.4 F.g⁻¹ , far surpassing conventional metal oxides. In addition, the HEO on screen printed electrode exhibited a notable increase in the oxidation peak current for the oxidation of dopamine, which can detect dopamine at nanomolar levels. • (Co 0.5 Ni 0.5 Mn 0.5 Mo 0.5 V 0.5 Zn 0.5 )O based HEO was successfully synthesized. • HEO offers multi-element interaction and facilitate fast ionic conductivity. • HEO exhibited high specific capacitance (698.4 F/g) in comparison with metal oxides. • HEO on SPE modified electrode improves detection of dopamine in nanomolar levels.