A cation chelation and reassembly route to synthesize P2-type Na0.67Ni0.26Mn0.67Mg0.07O2 cathode material for high performance sodium storage
【Abstract】
P2-type Na 2/3 Ni 1/3 Mn 2/3 O 2 (Na-NM) is an appealing cathode candidate for sodium-ion batteries (SIBs) but still suffers a fast capacity decay. Mg doping on the Ni-site in Na-NM cathode is an effective way to maintain structural stability, but how to achieve the uniform Mg dopant distribution is still a problem. Here, we report a facile cation chelation and reassembly route to prepare one-dimensional Na 0.67 Ni 0.26 Mn 0.67 Mg 0.07 O 2 (Na-NMM) cathode material with uniform element distribution. When evaluated as a cathode material for SIBs, the lower cut-off voltage could be set to 1.35 V so that an extra reversible capacity of 61 mAh g -1 is contributed from the Mn 4+ /Mn 3+ couple between 2 and 1.35 V, and a total reversible capacity of 173 mAh g -1 is achieved between 4.25 and 1.35 V at 0.1 C. Moreover, Na-NMM cathode shows good cycling performance with a reversible capacity of 83 mAh g –1 after 100 cycles at 1 C.
【Author】
Chouwei Xie, Xudong Ma, Ruimei Xu, Donghai Wang, Xiao Yu, Yong Liu
【Keywords】
sodium ion batteries, cathode, chelate, one dimensional structure, uniform element distribution 
【Journal】
ChemNanoMat(IF：3.4) Time：2021-09-18
