Plasma-induced chemical etching generating Ni_(3)S_(2) for formaldehyde detection

摘要

In this paper,Ni_(3)S_(2)nanosheet(NS)was generated by chemical etching with sodium sulfide directly on the nickel foam(NF),which was induced by dielectric barrier discharge plasma in liquid.Compared with other chemical etching methods of nickel-based nanomaterials,this method was not only rapid(40 min)and mild(at room temperature and atmospheric pressure),but also showed consistent stability and good reproducibility.The Ni_(3)S_(2)NS/NF electrode showed excellent performance in the electrochemical detection of formaldehyde under alkaline conditions.It had a good linear relationship with the concentration of formaldehyde in the range of 0.002-5.45 mmol/L(R^(2)=0.9957)and the limit of detection(LOD)was 1.23μmol/L(S/N=3).The sensitivity was 1286.9μA L mmol^(–1)cm^(–2),and the response time was about 5 s.The plasma-induced chemical etching strategy provides a simple and stable electrode preparation method,which has great application prospects in nonenzymatic electrochemical sensors.