Integration of surface modified aqueous ink for multi-functional material extrusion

The possibility to construct functional materials with designed shapes via 3d printing involves higher flexibility in the next-generation of our device. In order to formulate stable colloidal suspension with high solid loading, water-based ink allows particles dispersion by tuning surface chemistry. But it has been limited by material solubility in water. Moreover, tailoring ink formulation of different materials will increase the feasibility of wider materials combinations. Here, a facile method of polyvinylpyrrolidone coating of starting functional materials is been utilized, illustrating with zinc oxide as an example. Inks made with surface modified powder shows a typical shear thinning behavior. In addition, the printed samples are employed as adsorbents for removal of gaseous HCHO, and the sample with higher capping agent molecular weight offers better adsorption performance compared to other samples. Furthermore, compared with commercial Co Foam, the Tafel slope of the 3D Co is only 116.1 mV dec−1, exhibiting good hydrogen evolution reaction electrocatalytic kinetics, and demonstrating its wide potential in electrocatalytic field.