Electrochemical Detection Of Heavy Metal Ions In Water Based On Nickel-baseds Nanomaterials

With the rapid development of industries such as fertilizer and pesticide,heavy metal wastewater is often discharged directly or indirectly into the environment.Ingestion of these substances into the human body can lead to poisoning or cancer,posing a threat to human health.Therefore,researchers use corresponding technologies to detect heavy metal pollutants.Electrochemical technology is undoubtedly a good method.Through doping,defect engineering,and metal synergy,targeted design of nanomaterials has provided inspiration for designing sensitive sensing interfaces for inert pollutants.Nickel based nanomaterials have different valence states on the surface,which are prone to redox reactions,and have large reserves,low prices,and are easy to adsorb heavy metal pollutants.Studying the electrochemical detection sensing mechanism of nickel based nanomaterials has guiding significance for the design and synthesis of efficient electrode modification materials.The following work has been carried out for this purpose:（1）A non-precious metal nanosheet phosphorus doped nickel sulfide/nickel disulfide material was synthesized.The electrochemical sensing interface is constructed by template etching,hydrothermal synthesis,high-temperature calcination to manufacture defects,and chemical vapor deposition doping to obtain materials.We studied the mutual activation between non-metals and revealed the synergistic effect between vacancies and doped heteroatoms.The research shows that the incorporation of P can increase the electron density around the S site,and make the S site from competing with Pb（II）to providing electrons,promoting the reduction of Pb（II）.These findings have shown good electrocatalytic activity by utilizing the synergistic effect between non-metallic elements.The detection sensitivity reaches 83.42μA/μM.The detection limit is 0.048μM.And the material has excellent stability,reproducibility,anti-interference ability,and has the potential for practical testing.（2）NiCoSe₂ nanospheres were prepared by a two-step solvothermal method.Through conducting material conductivity tests,optimizing detection conditions,stability and reproducibility tests,and comparing the corresponding and real water samples of As（III）with different materials,it was found that the Ni（II）/Ni（III）and Co（II）/Co（III）cycles present in the material improved the electrocatalytic performance,and Ni and Co can activate each other to enhance their electron donating ability and promote the reduction of As（III）,The electrocatalytic performance is one order of magnitude higher than that of a single metal.The detection sensitivity is 0.34μA/ppb,with a detection limit of 5.5 ppb,which is lower than the international standard of 10 ppb,has excellent stability and reproducibility.The detection results in real water samples are close to the experimental standard results,indicating that the material has good application prospects in actual sample analysis.