Organic chemical sensor comprising plasma-deposited microporous layer, and method of making and using

A method of making an organic chemical analyte sensing element, comprising,

• providing a substrate with a conductive layer;
• forming a plasma from a gas mixture comprising an organosilane, oxygen, and a hydrocarbon;
• exposing the substrate with conductive layer thereupon to the plasma such that an amorphous random covalent network layer comprising at least about 30% carbon, and further comprising silicon, hydrogen, and oxygen, is formed atop the conductive layer;
• heating the amorphous random covalent network to form an analyte-responsive dielectric layer that comprises a microporous, hydrophobic, amorphous random covalent network having a mean pore size of less than about 10 nm and a porosity of at least about 20%;
• and,
• depositing a second conductive layer atop the analyte-responsive dielectric layer.

A method of making an organic chemical analyte sensing element, comprising,

• providing a substrate with first and second conductive electrodes that are in an interdigitated configuration with spaces in between;
• forming a plasma from a gas mixture comprising an organosilane, oxygen, and a hydrocarbon;
• exposing the substrate with conductive electrodes thereupon to the plasma such that an amorphous random covalent network layer comprising at least about 30% carbon, and further comprising silicon, hydrogen, and oxygen, is formed at least in the spaces in between the interdigitated electrodes;
• heating the amorphous random covalent network to form an analyte-responsive dielectric layer that comprises a microporous, hydrophobic, amorphous random covalent network having a mean pore size of less than about 10 nm and a porosity of at least about 20%.

A method of sensing organic chemical analytes, comprising:

• providing a sensor that comprises;
• a sensing element that comprises a first electrode and a second electrode and a microporous, hydrophobic, analyte-responsive dielectric material disposed at least in proximity to the first and second electrodes, wherein the microporous, hydrophobic analyte-responsive dielectric material comprises an amorphous random covalent network comprising at least about 30% carbon, and having a mean pore size of less than about 10 nm and a porosity of at least about 20%;
• and,
• an operating circuit in electrical communication with the first and second electrodes, wherein the operating circuit is capable of applying a voltage to the first and second electrodes and is capable of detecting a change in an electrical property of the sensing element;
• exposing the sensing element to an environment potentially containing one or more organic chemical analytes;
• applying a voltage to the first and second electrodes;
• and,
• monitoring an electrical property of the sensing element.