Bamboo derived cellulose nanofibers for high-performance Ni-Zn batteries: Enhancing rate capability by cobalt-doping

Suffering from sluggish kinetics and unstable architectures, the unsatisfied rate capability and poor cycling stability of nickel-based cathode hindered the widespread utilization of Ni-Zn batteries in fields of energy storage. Herein, we introduce suitable Co content to the nickel–carbon composite electrode materials and prepare a nickel-based cathode with 3D network structure using a carbon framework derived from bamboo cellulose nanofibers to anchor cobalt-doped nickel/nickel oxides (denoted as Co-Ni/NiO@C). Due to interlaced networks and abundant nanoscale metal sites, the Co-Ni/NiO@C owns abilities of fast electrons/ions transfer and efficient reversible reaction, which displays a high specific capacity of 241 mAh/g and excellent rate performance (78.1% retention after 20-folder current increase). When the Co-Ni/NiO@C was used as the cathode for a Ni-Zn battery, the battery exhibited a specific capacity of 321 mAh/g and retained 77.8% retention after a 20-folder current increase, indicating its good rate capability. Moreover, the Co-Ni/NiO@C//Zn battery also delivers an outstanding cycling performance (94.2% retention after 2500 cycles). Therefore, this work broadens the way to develop superior performance electrode materials derived from biomass carbon resources for large scale energy storage systems.