Towards an advanced 3D-printed catalyst for hydrogen peroxide decomposition: Development and characterisation

The propellant form of hydrogen peroxide is a non-toxic alternative to hydrazine. However, catalysts used to induce hydrogen peroxide decomposition are often plagued by low melting point, high pressure drop and poor activity. 3D-printing may offer solutions to many of these issues, through the realisation of complex geometries such as triply-periodic minimal surfaces (TPMS). In this work, methods to print and coat such ceramic catalyst supports were developed. A flow reactor was used to quickly screen the catalysts and assess the influence of the chosen active phase, precursor, and support sintering temperature on their intrinsic activity. Platinum prepared from H2PtCl6 emerged as the most active catalyst, with a support sintering temperature of 1200 degrees C yielding the highest BET surface area. The latter was strongly correlated to catalytic activity. On a per weight basis, the printed Pt catalyst outperformed conventional silver screens and also matched the performance of Pt on a high surface area commercial support, due to its egg-shell distribution. These findings have laid the groundwork for future testing in a thruster configuration, where the proposed advantages of the 3D-printed structures will be evaluated.