Spark ablation device
A spark ablation device for generating nanoparticles comprising a spark generator; the spark generator comprising first and second electrodes, wherein the spark generator further comprises at least one power source which is arranged to be operative at a first energy level for maintaining a discharge between the first and second electrodes, which power source is arranged for repetitively increasing the energy of the discharge to a predetermined secondary level that is higher than the first energy level for ablating a portion of the electrodes.
1. A spark ablation device for generating nanoparticles comprising:
an outlet for the generated nanoparticles; and
a spark generator comprising first and second electrodes, the spark generator comprising at least one power source which is arranged to be operative for maintaining a discharge between the first and second electrodes, wherein the at least one power source comprises a continuous DC or AC power source and a source for pulsed power, and wherein the at least one power source is configured for repetitively and intermittently varying its power output between a first energy level and a second energy level, wherein the first energy level maintains the discharge substantially continuously between the electrodes of the spark ablation device and the first energy level is insufficient to cause ablation of the electrodes, and the second energy level is higher than the first energy level and sufficient to cause ablation of the electrodes.
2. A spark ablation device according to claim 1 , wherein the source for pulsed power comprises a pulse generator for repetitively increasing the energy of the discharge.
3. A spark ablation device according to claim 1 , wherein the first energy level is selected at a level insufficient to generate the nanoparticles.
4. A spark ablation device according to claim 1 , wherein the second energy level is selected at a level to unavoidably generate the nanoparticles.
5. A spark ablation device according to claim 1 , wherein the at least one power source comprises (a) a current source, or (b) a voltage source.
6. A spark ablation device according to claim 1 , wherein the spark ablation device comprises an ignition circuit for initial ignition of the discharge.
7. A spark ablation device according to claim 1 , wherein the first and/or second electrodes are hollow.
8. A spark ablation device according to claim 7 , wherein the first and/or second electrode(s) are connected or connectable to a gas supply.
9. A spark ablation device according to claim 1 , wherein the spark generator further comprises means to provide a magnetic field in a discharge area between the first and second electrodes, wherein the means to provide a magnetic field provide a magnetic field with field lines substantially perpendicular to the electrical field lines causing the discharge between the electrodes so as to influence the location on the first and second electrodes at which the discharge occurs.
10. A spark ablation device according to claim 9 , wherein the electrodes are provided with magnets or electrical coils to provide the magnetic field lines.