1 

Interfacial Spinel Local Interlocking Strategy 

Towards Structural Integrity in P3 oxide Cathodes 

Jia-Yang Li a, Hai-Yan Hu b,c, Hong-Wei Li c, Yi-Feng Liu b,c, Yu Su b,c, Xin-Bei Jia b,c, Ling-Fei 

Zhao a, Ya-Meng Fan a, Qin-Fen Gu d, Hang Zhang c, Wei Kong Pang a,*, Yan-Fang Zhu b,c,*, Jia-

Zhao Wang a, Shi-Xue Dou a, Shu-Lei Chou b,c,*, and Yao Xiao b,c,*.  

a Institute for Superconducting and Electronic Materials Australian Institute for Innovative 

Materials University of Wollongong Innovation Campus, Squires Way, North Wollongong NSW 

2522, Australia. 

b College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035 P. R. 

China.  

c Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation 

Institute for Carbon Neutralization, Wenzhou 325035, China. 

d Australian Synchrotron, Clayton, VIC, 3168 Australia 

*Corresponding author. Email: wkpang@uow.edu.au; yanfangzhu@wzu.edu.cn; 

chou@wzu.edu.cn; xiaoyao@wzu.edu.cn. 

This WORD file includes: 

Figures S1 to S20 

Tables S1 to S2 

  



 

 

2 

Results and Discussion 

 

Figure S1 Full XPS sepctrum of NaMCM-600 powder. 

  



 

 

3 

 

Figure S2 Fine XPS sepctrum of a) Na, b) Mn, c) Co, and d) Mg in NaMCM-600 powder. 

  



 

 

4 

 

Figure S3 The results of peak current versus square root of the scan rate at different oxidation 

and reduction peaks of NaMCM-600. 



 

 

5 

 

Figure S4 The typical synchrotron-based XRD pattern selected at different stage of charge during 

the first charge/discharge of NaMCM-600. 

 

  



 

 

6 

 

Figure S5 Full XPS sepctrum of NaMCM-600 electrode after cycling with ion beam etching. 

  



 

 

7 

 

Figure S6 Fine XPS sepctrum of Co metal in NaMCM-600 electrode after cycling with ion beam 

etching. 



 

 

8 

 

Figure S7 Full XPS sepctrum of Na metal in NaMCM-600 cell after 100 cycles. 

 

  



 

 

9 

 

 

Figure S8 Corresponding galvanostatic charge/discharge curves versus specific capacity at 

different rates of NaMCM-650. 

 

  



 

 

10 

 

Figure S9 Corresponding galvanostatic charge/discharge curves versus specific capacity at 

different rates of NaMCM-700.  



 

 

11 

 

Figure S10 The results of peak current versus square root of the scan rate at different oxidation 

and reduction peaks of NaMCM-650. 

 

  



 

 

12 

 

Figure S11 The results of peak current versus square root of the scan rate at different oxidation 

and reduction peaks of NaMCM-700. 

  



 

 

13 

 

Figure S12 The SEM images of the morphlogy of a,b) NaMCM-600 and c,d) NaMCM-700 

cathode electrode after 100 cycles. 

 

  



 

 

14 

 

Figure S13 The electrochemical performance of NaMCM-600 and NaMCM-700 in voltage 1.5-

4.5V. 

 

  



 

 

15 

 

Figure S14 The profile curve of NaMCM-600 and NaMCM-700 at 1st and 2nd cycle. 

 



 

 

16 

 

Figure S15 The energy density-cycle data of NaMCM-700. 

 



 

 

17 

 

Figure S16 The typical synchrotron-based XRD pattern selected at different stage of charge during 

the first charge/discharge of NaMCM-700. 

 

  



 

 

18 

 

 

Figure S17 Full XPS sepctrum of Na metal in NaMCM-700 cell after 100 cycles. 

  



 

 

19 

 

 

Figure S18 Fine XPS sepctrum of Co metal in NaMCM-700 electrode after cycling with ion beam 

etching. 

 

  



 

 

20 

 

Figure S19 Full XPS sepctrum of Na metal in NaMCM-700 cell after 100 cycles. 

 

 

  



 

 

21 

 

Figure S20 Optical photograph of Na metal in NaMCM-600 and NaMCM-700 after 100 cycles. 

  



 

 

22 

 

Table S1 The element composition proportion of NaMCM-600 

Element Peak BE (eV) Atomic (%) 

Na 1071.36 29.65 

O 531.95 17.98 

F 684.35 10.89 

C 285.58 36.13 

Cl 199.56 4.83 

Mn 641.92 0.52 

 

  



 

 

23 

Table S2 The element composition proportion of NaMCM-700 

Element Peak BE (eV) Atomic (%) 

Na 1071.51 23.62 

F 684.79 14.25 

O 533.2 32.35 

C 286.44 26.77 

Cl 200.02 3