Nanoplotter for printing of High Surface Area Catalysts
For the analysis of High Surface Area Catalysts in the Scanning Flow Cell Setup a special preparation of the catalyst suspensions is necessary to enable defined and clean performance testing. To address this problem we are using a Nano-Plotter (Gesim, NP2.1, Fig.1), which is able to print nanoparticle suspensions with volumes down to hundreds of picoliters and therefore creates small spots of catalyst onto variable substrates (Fig.2). The Nano-Plotter includes basic components as the mobile dispensing system, a sample uptake station, a washing system and a stroboscope test. Additional features can be added if necessary.
The printing is done with piezopipettes, where a pressure pulse is generated to release a droplet from the printing nozzle (drop-on-demand). The size and velocity of the droplets can be adjusted by changing the voltage curve applied to the piezoelectric crystal. The performance of each individual suspension can be checked in the stroboscope camera. The printing procedure is programmed beforehand, so that the printing process of several suspensions is conducted automatically and with high reproducibility.
The printed catalyst locations have a diameter in the range of 500 µm and are well suited for the use with the SFC setup.