RGO-Modified paper supported Globe Thistles-Like NiCo2S4 flexible electrodes enhancing H2O2 sensing

Abstract

The Globe Thistles-Like (GTL) NiCo2S4 nanostructures were supported on reduced graphene oxide modified filter paper (FP). The prepared GTL NiCo2S4/rGO/FP is investigated as a disposable and flexible electrode for the electrochemical detection of H2O2 in alkaline media. Owing to the rich redox active sites, the synergistic effect between Co3+ and Ni2+, and the rapid electron transportation of substituting sulfur (S) for oxygen (O) in NiCo2O4, the GTL NiCo2S4/rGO/FP exhibits considerable enzyme-free H2O2 sensing performance with wide linear H2O2 ranging from 38.8 to 37306.8 μM, high sensitivity of 2.4326 mA mM−1 cm−2, and low detection limit of 0.08 μM. The GTL NiCo2S4/rGO/FP electrode has stable sensing performance and is highly selective toward analyte for physiological interfering species. The excellent electrochemical performance of GTL NiCo2S4/rGO/FP composite is attributed to the GTL structure of NiCo2S4. By studying the hydrothermal reaction time, electrochemical active surface area, and hydrophilic-hydrophobic surfaces of GTL NiCo2S4/rGO/FP composite, the relationship between the microstructure and sensing performance of the composite was elucidated. Surely this study opens up new possibilities for the application of low-cost, biodegradable flexible electrode materials in wearable sensors in the near future.