Lotus seedpods biochar decorated molybdenum disulfide for portable, flexible, outdoor and inexpensive sensing of hyperin

Biomass waste, a good candidate for advanced carbon materials for sustainable electrodes, is receiving more and more attention for high value-added materials because of its promising contribution to economic growth and sustainable development. We proposed a green co-hydrothermal approach to prepare lotus seedpods biochar (BC) decorated molybdenum disulfide (MoS 2 ) from waste lotus seedpods and precursors of MoS 2, and a portable, flexible, outdoor and inexpensive sensing platform for hyperin on the integrated flexible three-electrode using U-disk potentiostat with smartphone was successfully developed. Structure and properties of MoS 2 -BC were characterized, it was proved that BC improves microstructure and morphology, electronic conductivity, electrode stability and electrocatalytic properties of MoS 2 . Attributing to these impressive features, the detection signal of hyperin was significantly amplified by the MoS 2 -BC modified glass carbon electrode (GCE) in detection range of 0.01–21 μΜ with detection limit (LOD) of 5 nM. It was worth mentioning that the MoS 2 -BC modified screen-printed electrode (SPE) performs hyperin detection in range of 100 nM - 3 μM with LOD 50 nM (S/N = 3). The practicability of the proposed method confirmed that the portable, on-site, low-cost, and outdoor detection of hyperin was feasible and practical in comparison with traditional both electrochemical sensing and HPLC methods.