Research On Ethanol Sensors Fabricated With Molybdenum-based Micro-nano Arrays Electrode

With the development of communication electronic and microelectronic, the fabrication and category of sensors are increasing. Molybdenum-based metal material such as Mo O2, Mo O3 and Mo S2 are widely used in sensors, electrochemical capacitors and optoelectronic devices, due to their special molecular structure that leading to unique physical and chemical properties. The research on new type sensors has become a trend, which is based on micro-nano Molybdenum-based metal material.The design of programmable pulse electrochemical etching system based on Lab VIEW is the basic of this paper. The main work of this paper includes three studies such as preparation of metal molybdenum micro-nano arrays sensor substrate, study on the ethanol gas sensor based on Mo O3 micro-nano arrays structure and ethanol electrochemical sensor based on Pd-Mo micro-nano arrays structure. The main content of this paper as follows:1. The device of this system that named as programmable electrochemical pulse micro-nano arrays etching platform is constructing of PCI-6221 data acquisition card, programmable DC regulated power supply PSM-6003, temperature control system and halogen light irradiation, which is on the foundation of Lab VIEW.2. Based on the research of programmable pulse etching platform, with half galvanic battery principle, a molybdenum based micro-nano arrays sensor substrate has been prepared. The physical and chemical properties of the electrodes are characterized in detail.3. To prepare and characterize Mo O3 micro-nano arrays structure. The well Mo O3 micro-nano arrays structure is used as substrate of ethanol gas sensitivity test, and then a semiconductor gas sensing test platform has been built.4. Encapsulate Mo O3 micro-nano arrays structure electrode as semiconductor ethanol gas sensor. Results show that Mo O3 micro-nano arrays electrode semiconductor ethanol gas sensor has lower operating temperature and the optimum operating temperature is 235 ?. The final linear fitting equation is y=0.0184x+0.938, of which R2=0.937, under the ethanol gas concentration of 100~500 ppm. Detection limit is 30 ppm. Range is 30~1000 ppm.5. Objective to fabricate Pd-Mo micro-nano composite electrode, electroplating and annealing under N2 have been adopt in order to make Palladium particles depositing on Mo homogeneously. Study on the application of electrochemical ethanol sensor is launched in 0.1 M KOH with three electrode system. Pd-Mo micro-nano composite electrode is used as working electrode, aiming at discussing its catalytic oxidation characteristics to ethanol. After testing of Cyclic Voltammetry, getting three conclusions as follows: firstly, the linear fitting equation of oxidation peak's current value is y=0.0325x+11.82, of which R2=0.986, under the concentration of ethanol is 10~500 m M; secondly, sensitivity is 1.56 m A mmol-1L cm-2; thirdly, detection limit is 21 ?mol L-1, which is based on tripling signal noise ratio.It explores one method of processing metal micro-nano arrays substrate electrode for sensors, which is based on programmable pulse power supply with low cost. Try to modify metal micro-nano arrays and test sensors' sensitivity. To carry out a more comprehensive study and test of sensitivity with Mo O3 micro-nano arrays electrode based semiconductor ethanol gas sensor and Pd-Mo micro-nano composite electrode based electrochemical ethanol sensor. The research results have great scientific research and engineering application value for the research and development of new type of Molybdenum based micro-nano arrays.