A high strength and conductivity bulk Magneli phase Ti4O7 with superior electrochemical performance

Here we report for the first time that Magneli phase Ti4O7 electrode with super performance is successfully prepared by hot-pressed sintering of single-phase submicron Ti4O7 powders. The microstructure, mechanical properties, electrical conductivity and electrochemical performance of the Ti4O7 electrodes were also investigated. Results show that the compact and homogeneous bulk Ti4O7 without evident defects such as pores and cracks is achieved when the submicmn Ti4O7 powder was sintered at 1200 degrees C for 0.5 h. As a result, the bulk density of the Ti4O7 reaches its theoretical value (4.323 g cm(-3)). Additionally, it has excellent physical and chemical properties, including the mean values of hardness and Young's modulus of 15.20 +/- 0.42 and 247.40 +/- 6.70 GPa, respectively, the Vickers-hardness of 1165.5 +/- 9.5 HV, the highest known conductivity of 1252.5 S cm(-1), and the widest known electrochemical stability window of 4.19 V in 1 M NaCl solution.