High-entropy design of transition metal oxide semiconductors with ultra-low thermal conductivity

Metal oxides are used in a broad array of technological applications. However, only a small subset of oxide materials are semiconducting, which limits the range of chemical compositions available for engineering. Here we demonstrate a strategy for driving insulating metal oxides into a semiconducting state with ultra-low thermal conductivity (less than 1 W/m/K) by introducing configurational entropy. This change in electronic character is facilitated by cation mixing in a high-entropy phase, whi