Pd, Ni And Pd-Ni Alloy Nanostructure Electrodepositing

Nanowires have great applicational prospects as functional materials,magnetic materials,electronic materials and sensors etc. Compared with other sensor,nanowire sensors have more advantage,such as a short response time,high sensitivity and high selectivity etc,so they have broad applications in chemistry and biology. Pd nanowire sensors have unique strongpoint compared with conventional Pd sensor,so it is a ideal material used in hydrogen sensors. Pd—Ni nanowire hydrogen sensors can overcome all the limitations of hydrogen sensors at present,and have unexampled advantages,so they will become the most promising hydrogen sensors. Means of synthesizing nanowire such as template,or resembling to template,need to depend on templates or special substrates. These approachs cost highly,and make the preparing ptocess more complicated,and can not prepare nanowires in large area. An ideal approach for practical application of nanowires would circumvent technical and economic constraints of templating. Idea of low cost and facility to electrodeposit preparing nanowires in lage area,attracts many scientists to study.This Thesis focused on the synthesis of Pd, Ni and Pd-Ni nanowie arrays. Electrodeposit substrates ,electrolysing solution and electrode were selected according to experiment. Nanowires arrays of different forms and size were electrodeposited growth employing equipment describing in the paper. Concentration,PH value, electrodepositing potential and state of ice,which affects groth of nanowires,were studied. By lots time of experiment,looking for the best condition of fabricating nanowires , these electrodepositing conclusion were summed up. Optic microscope and scanning electron microscope(SEM)were employed to characterize the images. The research results are summarized as follows: 1,Nanowire arrays are fabricated in large area employing the experiment method in this paper. Groth conditions should be adjust in time,base on watching through optic microscope. Different patterns and size nanowire arrays are achieved. Experiment shows that , different material have different groth condition,different patterns and different difficulty.2,Experiment gained ,under this experiment method,Pd naonowire DC groth potential is near 1.6V,Ni nanowire DC groth potential is near 1.2V,Pd-Ni alloy nanowire DC groth potential is near 2.0V. They have one minimum value,nanowire can not be received below this value. Maybe this potential can not offer enough power to groth nanowire. Different kind of potential can fabricates nanowire of fferent patterns and diameter size,and decides groth rate and nanowre density in arrays. The condition including centration,PH value, electrodepositing potential and state of ice,is main factor,and determines that whether nanowres are gained or not,and nanowire property.3,Diameter of naonowire is from 100nm to several microns, and length is at the micron magnitude. Nanowire has a branch structure,so it has a big surface. If these materials are used in the sensor, sensitivity and response wiil be improved. Nanowires have a better mechanisim, it is able to bear rinsing from alcohol and water. Optic microscope and scanning electron microscope ( SEM ) were employed to characterize the images of nanowire. From SEM images, order nanowire arrays and diameter can be received. At big zoom SEM image, particle that consists nanowire can be saw, it diameter is about 100nm. These grains are close to each other.Pd nanowire arrays are a kind of excellent nano—materials used to assemble hydrogen sensors, Pd-Ni nanowire arrays can improve Pd hydrogen sensors. Pd-Ni nanowire hydrogen sensors will be the most promising and perfect sensors used in hydrogen environment, which can insure the safety and reliability of broad applications of hydrogen energy.