The invention provides a rhodium-doped tin dioxide nano-fiber sensitive material acetone sensor prepared on the basis of an electrospinning technique, and a preparation method and application in acetone steam detection aspect in indoor environment and belongs to the technical field of gas sensors. The rhodium-doped tin dioxide nano-fiber sensitive material acetone sensor prepared on the basis of the electrospinning technique comprises an Al2O3 insulated ceramic plate and rhodium ion-doped tin dioxide semiconductor nano-fiber sensitive material films, wherein two separate L-shaped gold electrodes are arranged on the front face of the Al2O3 insulated ceramic plate, a ruthenium oxide heating layer is arranged on the back face of the Al2O3 insulated ceramic plate and two separate rectangular gold electrodes are arranged on the surface of the ruthenium oxide heating layer; and the L-shaped gold electrodes and the front face of the Al2O3 insulated ceramic plate are coated with the rhodium ion-doped tin dioxide semiconductor nano-fiber sensitive material films. Through doping of rhodium ions, the morphological characteristics of tin dioxide semiconductor nano-fiber are changed on the one hand and the electron concentration in the tin dioxide material is reduced on the other hand, so that the sensitivity of the sensor is improved.

Rhodium-doped tin dioxide nano-fiber sensitive material acetone sensor prepared on the basis of electrospinning technique, and preparation method and application of acetone sensor

The invention discloses a sensitive material for detecting formaldehyde and a preparation method and application of the sensitive material. The sensitive material is a reduction graphene oxide-doped tin oxide nanosheet prepared by the steps of adsorbing a tin ligand to the surface of graphene oxide as a template, and carrying out thermal treatment; a mesoporous structure is arranged on the surfaceof the nanosheet; and the specific surface area of the nanosheet reaches 69.8m .g -105.7m .g by virtue of the ultrathin surface and the mesoporous structure on the surface, and more activesites are located on the surface. Therefore, a gas sensitive element in a gas sensor, prepared from the sensitive material, for detecting formaldehyde has the advantages that the formaldehyde sensitivity is high, the interference gas selectivity is good, the response/recovery capability is strong, the detection limit is low, the performance is stable and the like, so that the sensitivity and selectivity of a formaldehyde gas sensor can be effectively improved when the sensitive material is applied to the formaldehyde gas sensor. The sensitive material can be applied to the evaluation of air quality during the indoor and outdoor formaldehyde concentration detection.

Sensitive material for detecting formaldehyde and preparation method and application of sensitive material

The invention relates to a ferric oxide quantum dot enhanced graphene/tin oxide gas sensor and a preparation method thereof The graphene/tin oxide gas sensor is provided with a substrate, a conducting coating film layer, a tin oxide layer, a graphene layer and a ferric oxide quantum dot layer in sequence from bottom to top; the gas sensor is further provided with a first electrode and a second electrode; the first electrode is arranged on the conducting coating film layer; and the second electrode is arranged on the graphene layer The preparation method thereof comprises the following steps: firstly sedimentating the conducting coating film layer on the substrate, and then sedimentating the tin oxide layer; then transferring graphene onto the tin oxide layer; preparing the ferric oxide quantum dot layer on the graphene layer; and finally manufacturing the electrodes on the graphene layer and the conducting coating film layer respectively so as to obtain the gas sensor According to the ferric oxide quantum dot enhanced graphene/tin oxide gas sensor disclosed by the invention, the graphene/tin oxide gas sensor with high conversion efficiency is obtained by using a doping effect introduced with ferric oxide quantum dots

Ferric oxide quantum dot enhanced gas sensor and preparation method thereof

The invention provides a sensitive material for detecting acetone gas. The sensitive material is prepared by compounding a WO3 nano-sheet with C3N4, wherein the WO3 nano-sheet is used as a matrix, C3N4 is used as sensitizer, and the mass percentage of C3N4 in the sensitive material is between 0.5wt% and 10wt%. The invention also provides a preparation method of the sensitive material, which comprises: preparing an ultra-thin WO3 nano-sheet by a self-assembly method; ultrasonically peeling prepared C3N4 in a solvent to obtain a dispersion liquid; and dropwise adding the dispersion liquid to theWO3 nano-sheet layer according to the mass percentage to form a composite gas sensitive material. According to the invention, the acetone detection performance of the sensitive material is improved by modifying the WO3 nano-sheet with C3N4 with a two-dimensional layered structure. A gas sensitive test result shows that the gas sensitive element has the advantages of high sensitivity to acetone vapor, fast response recovery, good anti-interference ability, good stability and the like, and can be used to selectively detect acetone gas in respiratory gases.

Sensitive material for detecting acetone gas and preparation method thereof

The invention relates to the technical field of preparation methods of light-sensitive detectors and in particular relates to a ZnO nanowall RGO heterojunction photoelectric gas sensor and a preparation method thereof. The preparation method comprises the following steps: 1) preparing porous reduced graphene; 2) growing a ZnO seed layer in situ on the surface of RGO; 3) growing a ZnO nanowall in situ on the surface of RGO; and 4) ageing, so that the finished product is obtained. By realizing the technical scheme, the problems in the prior art that photosensitivity and NO2 sensitivity are low under the normal temperature condition are solved.

ZnO nanowall RGO heterojunction photoelectric gas sensor and preparation method thereof

The invention discloses a gas sensitive material for detecting low-concentration acetone and belongs to the technical field of gas sensitive materials. The gas sensitive material is composed of graphene quantum dot-SnO2, wherein the mass of graphene quantum dots is 5-15% of the total mass of the gas sensitive material. The sensitivity (the ratio of element resistance in the air to element resistance in gas to be detected), to acetone of 0.1 ppm, of an indirectly heated gas sensor prepared with the gas sensitive material as a sensitive material is 1.2-1.5 at the working temperature of 270 DEG C, and the sensitivity to acetone of 1000 ppm is 100-140. Response recovery time is smaller than 50 s. The sensitivity, to methanol, ethanol, methylbenzene, benzene and trimethylamine gas of 1000 ppm, of the element is lower than 4.1 at the same working temperature, and therefore quick detection of low-concentration acetone in the air can be achieved.

Gas sensitive material for detecting low-concentration acetone

The invention discloses a composite gas-sensitive material with high sensitivity and high selectivity on acetic acid gas, and belongs to the technical field of gas-sensitive materials. The composite gas-sensitive material consists of C3N4-SnO2, wherein the mass of C3N4 accounts for 8-12% of the total mass of the material; a heater type gas-sensitive sensor is prepared by taking the material as a sensitive material; when the sensor works at a working temperature of 185 DEG C, the sensitivity to 0.1ppm acetic acid is 1.1-1.3; the sensitivity of an element to 1,000ppm of the acetic acid reaches 35-90, while the sensitivity to 1,000ppm of acetone, formaldehyde, ethanol, acetaldehyde and ammonia gas is 8 or below, thereby proving that sensitivity and the gas sensitivity selectivity of tin dioxide to the acetic acid gas are improved by virtue of C3N4; and in addition, the working temperature of the detection acetic acid gas sensor is reduced, the concentration of acetic acid in air can be rapidly detected, and gas interference such as acetone, formaldehyde, ethanol, acetaldehyde, ammonia gas and the like can be eliminated.

Composite gas-sensitive material with high sensitivity and high selectivity on acetic acid gas

The invention discloses a graphene quantum dot-ZnO composite gas-sensitive material with high sensitivity to acetic acid gas and belongs to the technical field of gas-sensitive materials. The gas-sensitive material is prepared from ZnO and graphene quantum dots, wherein the mass of the graphene quantum dots accounts for 10% to 20% the total mass of the gas-sensitive material. A heater type gas sensor made by using the material as a sensitive material has the sensitivity (the ratio of element resistance in air to element resistance in detected gas) of 2 to 2.6 to 0.01ppm acetic acid at the working temperature of 300 DEG C and the sensitivity of 590 to 620 to 1,000ppm acetic acid, has the average response recovery time shorter than 45 seconds and can achieve rapid detection on concentration of the acetic acid in the air.

Graphene quantum dot-ZnO composite gas-sensitive material with high sensitivity to acetic acid gas

The invention discloses a high selectivity composite gas sensitive material used for detection of acetic acid gas in the air, and belongs to the technical field of gas sensitive material. The high selectivity composite gas sensitive material is C3N4-ZnO, the mass amount of C3N4 accounts for 5 to 20% of the total material mass; a side-heating gas-sensitive sensor is prepared from the high selectivity composite gas sensitive material, at 300 DEG C working temperature, the sensitivity on 0.1ppm acetic acid ranges from 1.2 to 1.4, the sensitivity on 1000ppm acetic acid ranges from 290 to 350, thesensitivity on 1000ppm acetone, formaldehyde, ethanol, acetaldehyde, and ammonia gas is lower than 31, it is shown that C3N4 is capable of increasing the sensitivity of zinc oxide on acetic acid gas,and increasing gas sensitive selectivity of zinc oxide on acetic acid gas, so that rapid detection of the concentration of acetic acid in the air is realized, and influences of acetone, formaldehyde,ethanol, acetaldehyde, and ammonia gas are eliminated.

High selectivity composite gas sensitive material used for detection of acetic acid gas in air

The invention discloses a tungsten oxide composite gas sensitive material used for detecting low concentration acetone gas, and belongs to the field of gas sensitive material. The tungsten oxide composite gas sensitive material used for detecting low concentration acetone gas is composed of WO3 and C3N4; the mass amount of C3N4 accounts for 1 to 5% of the total material mass; C3N4 in the tungstenoxide composite gas sensitive material is capable of increasing the sensitivity of tungsten oxide on acetone gas, reducing sensitivity of tungsten oxide on interface gas such as formaldehyde, and improving the gas sensitivity of the tungsten oxide composite gas sensitive material on acetone. A side-heating gas-sensitive element is prepared from the tungsten oxide composite gas sensitive material,at a working temperature of 310 DEG C, the sensitivity of the element on 1000ppm acetone ranges from 61 to 83, the sensitivity on 0.1ppm acetone gas ranges from 1.2 to 1.6, the response time and the recovery time on 0.1 to 1000ppm acetone gas are shorter than 60s, and the response time on 0.1ppm acetone is shorter than 10s. At a same working temperature, the sensitivity of the side-heating gas-sensitive element on 1000ppm formaldehyde is lower than 7, so that it is confirmed that the side-heating gas-sensitive element is high in gas sensitivity on acetone.

Dong Yongping

Papers

Gas sensitive material for detecting low-concentration acetone

Composite gas-sensitive material with high sensitivity and high selectivity on acetic acid gas

Graphene quantum dot-ZnO composite gas-sensitive material with high sensitivity to acetic acid gas

High selectivity composite gas sensitive material used for detection of acetic acid gas in air

Tungsten oxide composite gas sensitive material used for detecting low concentration acetone gas