Improved compaction of ZnO nano-powder triggered by the presence of acetate and its effect on sintering

Geologically-inspired strong bulk ceramics made with water at room temperature

Dense ceramic materials can form in nature under mild temperatures in water. By contrast, man-made ceramics often require sintering temperatures in excess of 1,400 °C for densification. Chemical strategies inspired by biomineralization processes have been demonstrated but remain limited to the fabrication of thin films and particles. Besides biomineralization, the formation of dense ceramic-like materials such as limestone also occurs in nature through large-scale geological processes. Inspired by the geological compaction of mineral sediments in nature, we report a room-temperature method to produce dense and strong ceramics within timescales comparable to those of conventional manufacturing processes. Using nanoscale powders and high compaction pressures, we show that such cold sintering process can be realized with water at room temperature to result in centimetre-sized bulk parts with specific strength that is comparable to, and occasionally even higher than, that of traditional structural materials like concrete.

Milder conditions for processing ceramics is of interest for a range of uses. Here authors report room temperature sintering of nanoparticulate powders using a solution-assisted route, yielding parts with centimetre-sized bulk parts with specific strength comparable to and possibly surpassing that of traditional structural materials like concrete.