Electron emitter structure, external photoelectric effect emitter, particle collecting device, tunnel surface emitter, semiconductor- based direct emitter and liquid ioniser comprising same, gas sensor comprising an emitter or emitter structure, method for generating free electrons, and method for collecting particles

A particle collection device comprising:

• an external photoelectric effect emitter comprising,
• an electron emitter structure comprising,
• an electron emission layer comprising a mixture of metals so as to be atmospherically stable, the electron emission layer being arranged to have a first side and a second side, and
• an electron accelerating structure arranged on the first side of the electron emission layer, the electron accelerating structure comprising at least one electrode which is electrically insulated from the electron accelerating structure so as to form an acceleration path which is configured to allow electrons which are released from the electron emission layer to be selectively accelerated upon generation of an adjustable electric field,
• wherein,
• the acceleration path has a length 1 of from 10 nm to 1 μm, and
• at least one UV LED which is configured,
• to release electrons from the electron emission layer, and
• to emit electromagnetic radiation at least partially onto the electron emission layer;
• and
• two plates which are electrically chargeable with a different polarity for generating an electric field, the two plates being arranged on the first side of and perpendicular to the electron emission layer and at a distance from each other.

A tunnel surface emitter comprising:

• an electron emitter structure comprising,
• an electron emission layer comprising a mixture of metals so as to be atmospherically stable, the electron emission layer being arranged to have a first side and a second side, and
• an electron accelerating structure arranged on the first side of the electron emission layer, the electron accelerating structure comprising at least one electrode which is electrically insulated from the electron accelerating structure so as to form an acceleration path which is configured to allow electrons which are released from the electron emission layer to be selectively accelerated upon generation of an adjustable electric field,
• wherein,
• the acceleration path has a length 1 of from 10 nm to 1 μm;
• an insulator layer arranged on the second side of the electron emission layer, the insulator layer having a layer thickness of between 0.5 nm and 6 nm;
• and
• a metal layer arranged on the insulator layer on a side which faces away from the electron emission layer, the metal layer having a layer thickness of between 0.5 nm and 6 nm,
• wherein,
• both a layer thickness of the electron emission layer and the layer thickness of the insulator layer is configured to be tunneled through.

A semiconductor based direct emitter for use in a surface chemistry, the semiconductor based direct emitter comprising:

• an electron emitter structure comprising,
• an electron emission layer comprising a mixture of metals so as to be atmospherically stable, the electron emission layer being arranged to have a first side and a second side, and
• an electron accelerating structure arranged on the first side of the electron emission layer, the electron accelerating structure comprising at least one electrode which is electrically insulated from the electron accelerating structure so as to form an acceleration path which is configured to allow electrons which are released from the electron emission layer to be selectively accelerated upon generation of an adjustable electric field,
• wherein,
• the acceleration path has a length 1 of from 10 nm to 1 μm;
• an insulator layer arranged on the second side of the electron emission layer, the insulator layer and having a layer thickness that is configured to be tunneled through;
• and
• a semiconductor arranged on a side of the insulator layer which faces away from the electron emission layer, the semiconductor comprising n doped regions and p doped regions which are arranged to alternate one next to another,
• wherein,
• the n doped regions and the p doped regions have boundary regions which are adjacent to the insulator layer.

A semiconductor based direct emitter comprising:

• an electron emitter structure comprising,
• an electron emission layer comprising a mixture of metals so as to be atmospherically stable, the electron emission layer being arranged to have a first side and a second side, and
• an electron accelerating structure arranged on the first side of the electron emission layer, the electron accelerating structure comprising at least one electrode which is electrically insulated from the electron accelerating structure so as to form an acceleration path which is configured to allow electrons which are released from the electron emission layer to be selectively accelerated upon generation of an adjustable electric field,
• wherein,
• the acceleration path has a length 1 of from 10 nm to 1 μm;
• an insulator layer arranged on a second side of the electron emission layer, the insulator layer having a layer thickness that is configured to be tunneled through;
• and
• a light emitting device selected from a VCSEL, a side emitting semiconductor laser or a light emitting diode, the light emitting device being arranged on a side of the insulator layer which faces away from the electron emission layer.

A method for generating free electrons of a defined low energy, the method comprising:

• providing an external photoelectric effect emitter comprising,
• an electron emitter structure comprising,
• an electron emission layer comprising a mixture of metals so as to be atmospherically stable, the electron emission layer being arranged to have a first side and a second side, and
• an electron accelerating structure arranged on the first side of the electron emission layer, the electron accelerating structure comprising at least one electrode which is electrically insulated from the electron accelerating structure so as to form an acceleration path which is configured to allow electrons which are released from the electron emission layer to be selectively accelerated upon generation of an adjustable electric field,
• wherein,
• the acceleration path has a length 1 of from 10 nm to 1 μm, and
• at least one UV LED which is configured,
• to release electrons from the electron emission layer, and
• to emit electromagnetic radiation at least partially onto the electron emission layer;
• releasing electrons from the electron emission layer using the at least one UV LED;
• and
• accelerating the released electrons via an electric field which is generated by applying a voltage between the electron emission layer and the at least one electrode.

A gas sensor comprising:

• an external photoelectric effect emitter comprising,
• an electron emitter structure comprising,
• an electron emission layer comprising a mixture of metals so as to be atmospherically stable, the electron emission layer being arranged to have a first side and a second side, and
• an electron accelerating structure arranged on the first side of the electron emission layer, the electron accelerating structure comprising at least one electrode which is electrically insulated from the electron accelerating structure so as to form an acceleration path which is configured to allow electrons which are released from the electron emission layer to be selectively accelerated upon generation of an adjustable electric field,
• wherein,
• the acceleration path has a length 1 of from 10 nm to 1 μm, and
• at least one UV LED which is configured,
• to release electrons from the electron emission layer, and
• to emit electromagnetic radiation at least partially onto the electron emission layer;
• an ion detection device;
• and
• a pressure reduction vessel in which the external photoelectric effect emitter and the ion detection device are arranged,
• wherein,
• a pressure in the pressure reduction vessel is reduced relative to an ambient pressure during an operation of the gas sensor.