Chitosan and chitosan oligosaccharide: Advanced carbon sources are used for preparation of N-doped carbon-coated Li2ZnTi3O8 anode material

Novel N-doped carbon coated Li 2 ZnTi 3 O 8 anode active materials are synthesized via one step high temperature calcination solid state reaction method using chitosan and chitosan oligosaccharide as advanced carbon sources. Coating a nano-thickness conductive N-doped carbon layer between particles is beneficial to enhance the electronic transmission speed. Physical characterization results show that all as-prepared samples have a cubic spinel structure with a P4 3 32 space group without any impurities, and the Li 2 ZnTi 3 O 8 with chitosan additive (molecular weight: 5000) has the best dispersity and smallest particle size in all as-prepared electrode materials . The length of organic compound molecular chain has a direct impact on the agglomeration of particles and reversible lithium intercalation capacity. When tested as the anode for lithium ion batteries , the optimal electrode material shows the largest discharge capacities and remarkable long-term cycling stability at a current density of 1.0, 2.0, and 5.0 A g − 1 over 500 cycles, respectively. Combining structural characterization with electrochemical performance, N-doped carbon layer, high degree of particle dispersibility and larger interface contact area are contributed to the enhancement of both electronic and ionic conductivities and of Li 2 ZnTi 3 O 8 .