Controllable Preparation And Application Of Silicon Nanowires And Magnesium-aluminum Oxide Nanostructures

In this paper,one-dimensional nanostructured materials of silicon nanowires and magnesium-aluminum oxide（Mg-Al spinel）were investigated.The growth conditions,growth mechanism and morphology control methods of one-dimensional nanostructures prepared by chemical vapor deposition（CVD）were systematically studied.The application of these one-dimensional nanomaterials in the field of electrochemistry were explored.Firstly,the silicon nanowires were prepared by DC arc plasma jet CVD.Silicon wafer was used as the substrate and silicon source,and nickel was used as catalyst to prepare silicon nanowires under the action of hydrogen / argon plasma.The results show that the size and morphology of silicon nanostructures mainly depends on the growth temperature and growth time,when the temperature reached 900 degrees,the growth time reaches 15 minutes,will be formed about 50 nm in diameter and length up to tens of micrometers of silicon nanowires.In addition,the silicon substrate can not only be laterally grown silicon nanowires,but also can form a pattern,which has potential application in the patterning technology.Secondly,Mg-Al spinel nano materials were prepared by the DC arc plasma jet CVD technology,aluminum sheet as the substrate and the source of aluminum,magnesium nitrate and nickel nitrate as a source of magnesium and nickel catalyst precursor.Mg-Al spinel nanostructures of diffrrent shapes were successfully prepared by adjusting the process parameters such as gas flow,power,and catalyst precursor content.The results show that the Mg-Al spinel nanostructures with Mg_0.36Al_2.44O₄ molecular formula,which is an one-dimensional nano material.Preparation of Mg-Al spinel using CVD is seldom reported in the literature,is a novel technology of preparation of magnesia alumina spinel.Finally,Mg_0.36Al_2.44O₄ nanowires-modified GCE(Mg_0.36Al_2.44O₄/GCE)was fabricasted via electrodeposition.The Mg_0.36Al_2.44O₄/GCE sensing electrode was constructed to explore the application of Mg-Al spinel in electrochemical sensor.Mg_0.36Al_2.44O₄/GCE-based electrochemical sensing system was developed for the detection of hydroquinone（HQ）,catechol（CC）,and resorcinol（RC）.The simultaneous detection of three dihydroxybenzene isomers was realized by adjusting the detection parameters such as the ionic strength and pH value of the electrolyte.The experimental results show that the resolution ability of the Mg_0.36Al_2.44O₄/GCE sensing electrode is the strongest when the electrodepostion time is 10 minutes.The Mg_0.36Al_2.44O₄/GCE sensing electrode for detecting three dihydroxybenzene isomers,has the advantages of high selectivity,low detection limit,high resolution and strong anti-interference ability,so the electrochemical detection method based on Mg_0.36Al_2.44O₄/GCE has a broad application prospect.