Strongly tribocatalytic dye degradation of high-entropy powder through harvesting friction

The omnipresent friction can be harvested to generate electricity, thereby facilitating redox reactions to degrade dye wastewater, which can be named as tribocatalysis. Here, it's experimentally found that the high-entropy CoCrFeMnNi powder synthesized via the Vacuum Induction Gas Atomization (VIGA) technique, can behave the obvious tribocatalytic Rhodamine B (RhB) dye degradation performance. In the tribocatalysis dye degradation process, friction occurs at the interface between the catalyst's surface and the stirring Teflon rod. The tribocatalytic RhB dye degradation ratios of the high-entropy CoCrFeMnNi powder catalysts at stirring speeds of 200 rpm, 400 rpm, 800 rpm, 1000 rpm, and 1200 rpm are 14.7 %, 70.3 %, 93.2 %, 99.4 %, and 99.8 %, respectively. It's also found that the RhB dye degradation ratio can be slightly enhanced under an external DC magnetic field provided by a commercial NdFeB magnet, which may be attributed to the magnetically-induced enhancement of separation efficiency of these positive and negative carriers. After being recycled for 3 times, the CoCrFeMnNi powder can still degrade 90.8 % RhB dye. The CoCrFeMnNi powder with the excellent tribocatalytic activity is potential for application in dye wastewater treatment through utilizing the friction energy in the environment.