Gas sensor and gas analysis multisensor chip based on graphene functionalized with carbonyl groups Russian patent published in 2021 - IPC G01N27/12 

FIELD: sensor technology; nanotechnology.

SUBSTANCE: invention relates to the field of sensor technology and nanotechnology, in particular to the development of gas sensors and multi-sensor lines of the chemoresistive type used for gas detection. The gas detector includes a dielectric substrate on which there are coplanar strip electrodes made of noble metal, thermistors and heaters, while a layer of graphene functionalized with carbonyl groups is used as a gas-sensitive material, which at the first stage is synthesized by using the method of liquid-phase modification of graphene oxide suspension by adding a weighed portion of powder sodium silicate in the ratio of 1.3-3.3 g/l in water or organic suspension of graphene oxide in the concentration of 1-5 weight. %, thoroughly stirring the mixture until the hydrogen index in the suspension reaches pH 9-9. 5 and heating the resulting suspension for 48-52 hours at a temperature of 75-85C, at the second stage, to purify the suspension from the reaction by-products, it is centrifuged at a speed of 12000-12500 rpm for 15-20 minutes, the supernatant is removed, the resulting precipitate is diluted with a solution of HCl in a concentration of 0.05-0.1% in a ratio of 10-70 g/l,is removed, the resulting precipitate is diluted with a solution of HCl, of a concentration of 0.05-0.1% in a ratio of 10-70 g/l, stirred for 2-5 minutes, and centrifuged at a speed of 12,000-12,500 rpm for 15-20 minutes; the supernatant is then removed, the resulting precipitate is diluted with deionized water to a concentration of 0.1-0.4 wt. % and setting the pH value of 5.5-6, resulting in a suspension, containing graphene functionalized with carbonyl groups, at the third stage, a suspension containing graphene functionalized with carbonyl groups is applied in the form of a thin film, up to 120 nm thick, to the surface of the sensor or chip substrate, after which that is air dried at room temperature for 10-12 hours and heated to 70-80C for 1-2 hours.

EFFECT: technical result is the creation of a chemoresistive gas sensor with high selectivity.

5 cl, 11 dwg