Carbon intercalated porous NaTi₂(PO₄)₃ spheres as high-rate and ultralong-life anodes for rechargeable sodium-ion batteries

In this manuscript, a carbon intercalated porous NaTi₂(PO₄)₃ (NTP@C) spherical composite was synthesized through a facile hydrolysis reaction combined with a subsequent hydrothermal and annealing process. Benefiting from the unique mesoporous architecture combined with the conductive carbon layer, the NTP@C composite showed excellent electrochemical properties in terms of both stable cycling performance and good rate capabilities. Evaluated as anodes for sodium-ion batteries, the NTP@C composites presented a high reversible specific capacity (around 134 mA h g^-1 at a current rate of 1C) and an excellent cycling performance (about 81 mA h g^-1 at a high current rate of 50C during the 1000th cycle). The remarkable electrochemical performance can be attributed to the rational design of the hybrid structure, which can ensure fast electron and sodium ion transport in the electrode materials.