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CN-121994883-A - Pd modified SnO2Preparation method of sensitive material of hydrogen sensor

CN121994883ACN 121994883 ACN121994883 ACN 121994883ACN-121994883-A

Abstract

The invention discloses a preparation method of a Pd-modified-based SnO 2 hydrogen sensor sensitive material, which comprises the steps of dissolving a certain proportion of stannous chloride dihydrate and polyvinylpyrrolidone in a solvent to obtain a uniform mixed solution, carrying out solvothermal reaction, washing, drying and calcining on the mixed solution to obtain pure SnO 2 nano powder, then carrying out ultrasonic dispersion on the obtained nano SnO 2 powder in ethanol, adding PdCl 2 solution for uniform dispersion, and drying and calcining at a high temperature to obtain the nano SnO 2 nano powder. The sensitive material of the hydrogen sensor has good response to low-concentration hydrogen, and can be used for leakage detection of low-concentration hydrogen.

Inventors

  • WANG YINGYUE
  • ZHANG GUOJIAN
  • HUANG JINYANG

Assignees

  • 中国民航大学

Dates

Publication Date
20260508
Application Date
20241101

Claims (5)

  1. 1. A preparation method of Pd modified SnO 2 hydrogen sensor sensitive material comprises the following steps: a) Dissolving stannous chloride dihydrate and polyvinylpyrrolidone into a solvent to obtain a mixed solution, transferring the solution into a reaction kettle for hydrothermal reaction, and washing, drying and calcining the obtained precipitate to obtain pure SnO 2 powder; b) Ultrasonically dispersing the SnO 2 prepared in the previous step into ethanol, adding a quantitative PdCl 2 solution, uniformly mixing and drying; c) Calcining the dried product in a muffle furnace to prepare a Pd modified SnO 2 hydrogen sensor sensitive material;
  2. 2. The preparation method of the hydrogen sensor sensitive material according to claim 1, wherein the mass ratio of stannous chloride dihydrate to polyvinylpyrrolidone in step a) is 3:7-1:1, and the dissolution is a mixed solution of ethanol and DMF, wherein the volume ratio of ethanol to DMF is 1:2-2:1;
  3. 3. The method for preparing a hydrogen sensor sensitive material according to claim 1, wherein the hydrothermal reaction temperature in step a) is 100-180 ℃, the reaction time is 10-18 hours, and the calcination temperature of the obtained precipitate is 300-500 ℃;
  4. 4. The method for preparing a hydrogen sensor sensitive material according to claim 1, wherein the adding amount of PdCl 2 in the step b) is 0.5wt.% to 2.0wt.% of Pd/Sn, and the drying temperature of the mixed solution is 60 ℃ to 90 ℃;
  5. 5. the method for preparing a hydrogen sensor sensitive material according to claim 1, wherein the calcination temperature of the product in step C) is 300 ℃ to 500 ℃.

Description

Preparation method of Pd modified SnO 2 hydrogen sensor sensitive material Technical Field The invention relates to the technical field of gas sensors, in particular to a preparation method and application of a Pd modified SnO 2 hydrogen sensor sensitive material. Background As one of the new generation clean energy sources, the hydrogen energy has obvious advantages and wide application. But the hydrogen has small molecule, low ignition energy and wide flammable range, is extremely easy to leak and cause deflagration in the production, transportation, storage and application processes, and causes casualties and property loss. Therefore, developing a fast, sensitive and reliable hydrogen sensor to monitor the leaked hydrogen in the environment in real time is particularly important to ensure the safety of the hydrogen energy related industry. The semiconductor hydrogen sensor has high sensitivity, good stability and low cost, but the practical application in the field of hydrogen safety is restricted by the excessively high working temperature. The noble metal doping is a very effective method for improving the semiconductor hydrogen sensor, and the traditional noble metal loading method is a method for reducing by using reducing agents such as traps, sodium borohydride and the like, so that the process is complicated, the time consumption is long, and therefore, a simple and easy noble metal modification method is urgently needed to improve the gas sensitivity performance of the semiconductor hydrogen sensor. Disclosure of Invention The invention aims to provide a preparation method of a Pd modified SnO 2 hydrogen sensor sensitive material, which has certain universality for modification of metal oxide sensor sensitive materials. The invention provides a preparation method of a Pd modified SnO 2 hydrogen sensor sensitive material, which comprises the following steps: a) Dissolving stannous chloride dihydrate and polyvinylpyrrolidone into a solvent to obtain a mixed solution, transferring the solution into a reaction kettle for hydrothermal reaction, and washing, drying and calcining the obtained precipitate to obtain pure SnO 2 powder; b) Ultrasonically dispersing the SnO 2 prepared in the previous step into ethanol, adding a quantitative PdCl 2 solution, uniformly mixing and drying; c) Calcining the dried product in a muffle furnace to prepare a Pd modified SnO 2 hydrogen sensor sensitive material; Preferably, the mass ratio of stannous chloride dihydrate to polyvinylpyrrolidone in the step a) is 3:7, and the solution is a mixed solution of ethanol and DMF, wherein the volume ratio of ethanol to DMF is 1:1; Preferably, the hydrothermal reaction temperature in step a) is 150 ℃, the reaction time is 12 hours, the calcination temperature of the obtained precipitate is 400 ℃, and the calcination time is 2 hours; The addition amount of the PdCl 2 solution in the step b) is 0.75wt.% Pd/SnO 2, and the drying temperature of the mixed solution is 80 ℃. Preferably the calcination temperature of the product of step C) is 400 ℃ and the calcination time is 2 hours. The invention provides a preparation method of a Pd modified SnO 2 hydrogen sensor sensitive material, which can be prepared by adopting the scheme. Compared with the prior art, the invention provides a preparation method of a Pd modified SnO 2 hydrogen sensor sensitive material, which comprises the following steps of a) dissolving stannous chloride dihydrate and polyvinylpyrrolidone into a solvent to obtain a mixed solution, transferring the solution into a reaction kettle to perform hydrothermal reaction, washing, drying and calcining the obtained precipitate to obtain pure SnO 2 powder, b) ultrasonically dispersing the SnO 2 prepared in the previous step into ethanol, adding a quantitative PdCl 2 solution, uniformly mixing and drying, and c) calcining the dried product in a muffle furnace to obtain the Pd modified SnO 2 hydrogen sensor sensitive material. The hydrogen sensor prepared by the sensitive material has effective response to 50ppm hydrogen, so that the hydrogen sensor has certain application value in the field of low-concentration hydrogen detection. Drawings FIG. 1 is an SEM image and an EDS image of 0.75wt.% Pd doped SnO 2 obtained in example 1 FIG. 2 is a comparison of the response of pure SnO 2 and 1wt.% Pd-doped SnO 2 sensitive material to 50ppm hydrogen in example 2 Detailed Description In order to make the implementation of the present invention more clear, the following detailed description will be given with reference to the accompanying drawings. Embodiment 1 is a preparation method of a Pd-modified SnO 2 hydrogen sensor sensitive material, and a solution impregnation method is adopted to prepare a Pd-SnO 2 nano material with uniform morphology and particles. In this embodiment, the following steps are mainly performed: a) Dissolving 0.5g of tin dichloride dihydrate and 0.7g of polyvinylpyrrolidone in a mixed solution of 20ml of ethan