Pyrochlore phase (Y,Dy,Ce,Nd,La) 2 Sn 2 O 7 as a superb anode material for lithium-ion batteries

High-entropy pyrochlore oxide (Y,Dy,Ce,Nd,La) 2 Sn 2 O 7 has been synthesized by the co-precipitation method. EDS and XPS analysis demonstrated the high-entropy structure in M 2 Sn 2 O 7 (M = Y, Dy, Ce, Nd, La) ultrafine powders, which is developed as the active material in lithium anode. The effects of different binders on the cycling performance and rate capability were discussed. Benefiting from the synergistic effects of high-entropy system and the strong intermolecular force provided by the sodium carboxymethyl cellulose (CMC) system, the optimized M 2 Sn 2 O 7 /CMC (M = Y, Dy, Ce, Nd, La) delivers a high initial discharge capacity of about 766 mAh g −1 and exhibits excellent cycle stability. A reversible capacity of 396 mAh g −1 and superior delivering retention of ~ 100% can be obtained at 100 mA g −1 after 100 cycles. Meanwhile, the capacity retention rate of 54.5% can still be reached after the cycling at various current densities from 0.05 to 1 A g −1 , demonstrating potential application prospect of the M 2 Sn 2 O 7 /CMC.