Ion beam generator (10, 110, 210), comprising: - an emission electrode (12, 212) comprising a first main surface; - an extraction electrode (14, 114, 214) comprising a second main surface arranged substantially facing the first main surface, said first and second main surfaces being separated by a gap; and - an electrical generator capable of applying a potential difference between the emission electrode and the extraction electrode; the emission electrode comprising an ionic liquid ion source, said emission electrode thus being capable of sending at least one beam of ions originating from said ionic liquid to the extraction electrode; characterized in that: - the emission electrode comprises a substrate and a plurality of nanowires extending from said substrate, substantially in the direction of the extraction electrode, each of said nanowires having a length comprised between 50 nm and 50 μm, preferentially comprised between 100 nm and 1 μm, each of said nanowires having a diameter comprised between 50 nm and 200 nm, a minimum distance between two adjacent nanowires on the substrate being comprised between 50 nm and 200 nm and preferentially equal to approximately 150 nm; - the ionic liquid ion source comprises a layer of ionic liquid formed on the substrate and at least partially immersing the nanowires, said layer of ionic liquid thus at least partially forming the first main surface; and - the plurality of nanowires and the substrate are electrically insulating, the electrical generator being connected to the layer of ionic liquid. - an emission electrode (12, 212) comprising a first main surface; - an extraction electrode (14, 114, 214) comprising a second main surface arranged substantially facing the first main surface, said first and second main surfaces being separated by a gap; and - an electrical generator capable of applying a potential difference between the emission electrode and the extraction electrode; the emission electrode comprising an ionic liquid ion source, said emission electrode thus being capable of sending at least one beam of ions originating from said ionic liquid to the extraction electrode; characterized in that: - the emission electrode comprises a substrate and a plurality of nanowires extending from said substrate, substantially in the direction of the extraction electrode, each of said nanowires having a length comprised between 50 nm and 50 μm, preferentially comprised between 100 nm and 1 μm, each of said nanowires having a diameter comprised between 50 nm and 200 nm, a minimum distance between two adjacent nanowires on the substrate being comprised between 50 nm and 200 nm and preferentially equal to approximately 150 nm; - the ionic liquid ion source comprises a layer of ionic liquid formed on the substrate and at least partially immersing the nanowires, said layer of ionic liquid thus at least partially forming the first main surface; and - the plurality of nanowires and the substrate are electrically insulating, the electrical generator being connected to the layer of ionic liquid. the emission electrode comprising an ionic liquid ion source, said emission electrode thus being capable of sending at least one beam of ions originating from said ionic liquid to the extraction electrode; characterized in that: - the emission electrode comprises a substrate and a plurality of nanowires extending from said substrate, substantially in the direction of the extraction electrode, each of said nanowires having a length comprised between 50 nm and 50 μm, preferentially comprised between 100 nm and 1 μm, each of said nanowires having a diameter comprised between 50 nm and 200 nm, a minimum distance between two adjacent nanowires on the substrate being comprised between 50 nm and 200 nm and preferentially equal to approximately 150 nm; - the ionic liquid ion source comprises a layer of ionic liquid formed on the substrate and at least partially immersing the nanowires, said layer of ionic liquid thus at least partially forming the first main surface; and - the plurality of nanowires and the substrate are electrically insulating, the electrical generator being connected to the layer of ionic liquid. - the emission electrode comprises a substrate and a plurality of nanowires extending from said substrate, substantially in the direction of the extraction electrode, each of said nanowires having a length comprised between 50 nm and 50 μm, preferentially comprised between 100 nm and 1 μm, each of said nanowires having a diameter comprised between 50 nm and 200 nm, a minimum distance between two adjacent nanowires on the substrate being comprised between 50 nm and 200 nm and preferentially equal to approximately 150 nm; - the ionic liquid ion source comprises a layer of ionic liquid formed on the substrate and at least partially immersing the nanowires, said layer of ionic liquid thus at least partially forming the first main surface; and - the plurality of nanowires and the substrate are electrically insulating, the electrical generator being connected to the layer of ionic liquid.