CTAB assisted in the synthesis of scandium doped-induced oxygen vacancy porous CoMoO4 positive electrode and MoO3-CNTs negative electrode to construct ultra-high performance supercapacitors
Tenghao Ma, Li An, Jian Hao, Tingting Hao, Jing Wang
Abstract
In this paper, we present an effective strategy to significantly enhance the electrochemical performance of CMO (CoMoO 4 ) through doping rare earth elements (Sc) to induce the formation of oxygen-generating vacancies, combined with cetyltrimethylammonium bromide (CTAB)-assisted synthesis. Sc doping improves the conductivity and charge transfer rate of the CMO material while enhancing the permeability and ion transport capacity of the electrolyte by inducing oxygen vacancies . Additionally, the introduction of CTAB promotes the formation of a porous structure in the material, increasing the specific surface area and further enhancing electrochemical performance. Experimental results show that the specific capacitance of the CMO-SC-CTAB electrode reaches 1765 F/g at a current density of 1 A/g, significantly higher than that of unmodified CMO (1052 F/g). After 10,000 cycles, its capacitance retention rate is 99.3 %, indicating excellent cycle stability. Meanwhile, molybdenum trioxide (MoO 3 ) was loaded onto carbon nanotubes (CNTs) as the negative electrode material for supercapacitors (MoO 3 -CNTs). This synergistic effect significantly increased the specific capacitance to 1130 F/g at a current density of 1 A/g, far exceeding that of CNTs alone. Importantly, asymmetric supercapacitors (ASCs) assembled with the optimized CMO-Sc-CTAB positive electrode and MoO 3 -CNTs negative electrode exhibited outstanding performance, achieving an energy density of 52.5 Wh/kg and a power density of 13,000 W/kg. These results underscore the great potential of this strategy for high-energy storage applications.