Significant regulation of structure and electrical performance of SiCN ceramics through high‐pressure sintering

Abstract This study was the first to investigate the influence of high‐pressure sintering (HPS) on the electrical conductivity of polymer‐derived SiCN ceramics (PDCs‐SiCN). The results showed that at the same temperature conditions (1000°C), the electrical conductivity of PDCs‐SiCN produced through high‐pressure sintering (SiCN‐HPS) was over 185 times higher than that of produced by conventional sintering (CS) in a furnace. X‐ray diffraction (XRD) patterns confirmed that both samples retained an amorphous structure without noticeable crystallization. Chemical composition, Raman spectroscopy and transmission electron microscopy (TEM) analyses revealed that HPS not only promoted the precipitation of free carbon in PDCs‐SiCN but also significantly increased its ordering. Furthermore, compared to SiCN‐CS, the SiCN‐HPS exhibited a significantly increased density (2.59 g/cm 3 ) and reduced porosity (0.54%). These results demonstrated that HPS effectively regulated the amount, distribution, and structure of free carbon within PDCs‐SiCN, while reducing the formation of insulating pores, which substantially improved conductivity. In addition, the SiCN‐HPS also exhibited excellent temperature‐resistance response, highlighting HPS as a promising strategy for developing high‐performance silicon‐based engineered PDCs.