Spark ablation is a highly effective and versatile method for producing nanoparticles from bulk conductive electrode materials. For a number of applications, however, the production throughput of the process needs to be increased with respect to the current state of the art. Here we show that this can be achieved by decreasing the diameter of the employed bulk-material electrodes from ca. 12 to 0.15 mm, corroborating previous observations, and demonstrate that the throughput is associated with the ablation efficiency (i.e., the energy spent to produce nanoparticles per total input energy) that respectively increases by a factor of 10. It is also shown that the commonly used theory for predicting the mass of nanoparticles produced by spark ablation cannot capture this effect, and thus we extend it to account for heat losses that affect the process when electrode diameter reduces below ca. 2 mm. Through this exercise we also show that reduced heat losses associated with thinner electrodes provide an effective recipe to increase the ablation efficiency, also referred as the nanoparticle production yield. The new extended theory for estimating spark ablation nanoparticle mass production throughput is also accompanied by an empirical equation predicting its dependence on electrode diameter.

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Porous layers composed of nanoparticles (NPs) have a wide range of (potential) applications including catalysts, (chemical) sensors, thermoelectric materials and electronics. These application domains will profit strongly from our NP printing process which is flexible with respect to i) the composition of the NPs and ii) the possibility of composing arbitrary mixtures of different NPs (external mixtures). Our printer is a combination of a spark ablation NP generator supplying unagglomerated 5 nm particles with a hypersonic impactor equipped with an xyz stage. The profiles of printed lines are measured, and the impact velocity is described by theory. Printed gold lines on a polymer contact lens are sufficiently sintered by the impact energy to show the plasmon mode of gold (“golden“ color).@en