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To optimize the potential window and maximize the utilization of the capacity of both negative and positive electrodes, rational design of electrode materials are critically important in full-cell construction of rechargeable batteries. In this work, we propose and fabricate a carbon-confined V2O3/Ni2P/C composite structure for excellent performance lithium ion batteries by taking advantage of the high capacity of V2O3 and low potential of Ni2P. The full cell constructed with V2O3/Ni2P/C as anode and commercial LiMn2O4 as cathode offers a record high energy density of 361.5 Wh kg–1 and excellent cycle stability, outperforming the state-of-the-art work reported in literature.

An ultrathin MnO2 sheet assembled three-dimensional flower microsphere grown on nitrogen-doped graphene is synthesized through a hydrothermal treatment method. When tested as an anode in a lithium-ion battery, the obtained material exhibits a high discharge capacity of 993 mAh g–1 in the second cycle at 0.1 A g–1, which goes up to 2243 mAh g–1 gradually after 135 charge/discharge cycles. This phenomenon turns out to be related to the deep coupling between nitrogen-doped graphene and MnO2 caused by morphology evolution of the composite upon cycling. Also, kinetics analysis reveals the elevated capacitive contribution after cyclic reaction, indicating the ever enhanced phase interface charge storage mechanism associated with the morphology evolution. Otherwise, the first-principles calculations also indicate the electronic structure of MnO2 can be efficiently modulated by coupling with a conductive graphene substrate, through a covalent C–Mn or N–Mn bond; thus, the deep coupling between nitrogen-doped graph...

A multihierarchical structure with (NH4)(Ni, Co)PO4·0.67H2O microplatelets and (Ni, Co)3(PO4)2·8H2O ultrathin nanopieces anchored on reduced graphene oxide (NCNP/RGO) is synthesized via a mild hydrothermal approach. This unique interface-rich structure is suitable for a high power energy storage device by providing efficient pathways for both electronic conduction and ionic transportation, which are effective ways to improve the electrochemical performance. Specifically, a specific capacity of 993 F g–1 is obtained in the three-electrode measurement, with ultrahigh capacity retention of 81.2% (807 F g–1) from 0.5 to 32 A g–1. The hybrid device constructed with the as-prepared NCNP/RGO as anode and a hierarchical porous carbon (HPC) as cathode offers a very superior energy density of 42.1 Wh kg–1 at a power density of 73 W kg–1, which remains 32 Wh kg–1 at 14 kW kg–1. Meanwhile, the as-prepared hybrid capacitor exhibits a remarkable cycling stability (96.5% capacitance retention after 10 000 cycles). The c...

In this work, we propose a one-step process to realize the in situ evolution of molybdenum carbide (Mo2C) nanoflakes into ordered mesoporous carbon with few-layered graphene walls (OMG) by chloridization and self-organization, and simultaneously the Cl-doping of OMG (OMG-Cl) by modulating chloridization and annealing processes is fulfilled. Benefiting from the improvement of electroconductivity induced by Cl-doping, together with large specific surface area (1882 cm2 g–1) and homogeneous pore structures, as anode of lithium ion batteries, OMG-Cl shows remarkable charge capacity of 1305 mA h g–1 at current rate of 50 mA g–1 and fast charge–discharge rate within dozens of seconds (a charge time of 46 s), as well as retains a charge capacity of 733 mA h g–1 at a current rate of 0.5 mA g–1 after 100 cycles. Furthermore, as a promising electrode material for supercapacitors, OMG-Cl holds the specific capacitances of 250 F g–1 in 1 M H2SO4 solution and 220 F g–1 at a current density of 0.5 A g–1 in 6 M KOH solu...