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The development of lithium-sulfur batteries (LSBs) is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect. Herein, an N, O co-doped graphene layered block (NOGB) with many dents on the graphene sheets is designed as effective sulfur host for high-performance LSBs. The sulfur platelets are physically confined into the dents and closely contacted with the graphene scaffold, ensuring structural stability and high conductivity. The highly doped N and O atoms can prevent the shuttle effect of sulfur species by strong chemical adsorption. Moreover, the micropores on the graphene sheets enable fast Li + transport through the blocks. As a result, the obtained NOGB/S composite with 76 wt% sulfur content shows a high capacity of 1413 mAh g -1 at 0.1 C, good rate performance of 433 mAh g -1 at 10 C, and remarkable stability with 526 mAh g -1 at after 1000 cycles at 1 C (average decay rate: 0.038% per cycle). Our design provides a comprehensive route for simultaneously improving the conductivity, ion transport kinetics, and preventing the shuttle effect in LSBs.

The cost-efficient ZnMnO 3 has attracted increasing attention as a prospective anode candidate for advanced lithium-ion batteries (LIBs) owing to its resourceful abundance, large lithium storage capacity and low operating voltage. However, its practical application is still seriously limited by the modest cycling and rate performances. Herein, a facile design to scalable synthesize unique one-dimensional (1D) mesoporous ZnMnO 3 nanorods (ZMO-NRs) composed of nanoscale particles (≈11 nm) is reported. The 1D mesoporous structure and nanoscale building blocks of the ZMO-NRs effectively promote the transport of ions/electrons, accommodate severe volume changes, and expose more active sites for lithium storage. Benefiting from these appealing structural merits, the obtained ZMO-NRs anode exhibits excellent rate behavior (≈454 mAh g -1 at 2 A g -1 ) and ultra-long term cyclic performance (≈949.7 mAh g -1 even over 500 cycles at 0.5 A g -1 ) for efficient lithium storage. Additionally, the LiNi 0.8 Co 0.1 Mn 0.1 O 2 //ZMO-NRs full cell presents a practical energy density (≈192.2 Wh kg -1 ) and impressive cyclability with approximately 91 % capacity retention over 110 cycles. This highlights that the ZMO-NRs product is a highly promising high-rate and stable electrode candidate towards advanced LIBs in electronic devices and sustainable energy storage applications., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Perovskite oxides have attracted much attention for enabling the oxygen-evolution reaction (OER) over the past decades. Nevertheless, their poor conductivity is still a barrier hindering their use. Herein, we report a catalyst prototype of Co-based antiperovskite nitrides CuNCo 3- x V x (0 ≤ x ≤ 1) to be a highly effective OER electrocatalyst. The synthesized CuNCo 3- x V x exhibits greatly enhanced activity and stability toward the OER in alkaline medium. The CuNCo 2.4 V 0.6 shows a mere 235 mV of overpotential to reach 10 mA cm -2 , which is comparable to that of Ir/C (232 mV). More importantly, the CuNCo 2.4 V 0.6 is more durable than the conventional Ir/C catalyst. The CuNCo 2.4 V 0.6 catalyst enabled a Zn-air battery to exhibit a cycle life of 143 h with a much higher cell efficiency. The V-substituted CuNCo 2.4 V 0.6 provides a higher content of the desirable Co 3+ species in the post-OER catalyst, which ensures a high activity over a long-term operation. With these enhanced effects enabled by the compositional flexibility of CuNCo 3- x V x antiperovskite nitride, a feasible strategy for optimizing an electrocatalyst with tunable properties is provided.

To optimize the cycle life and rate performance of lithium-ion batteries (LIBs), ultra-fine Fe 2 O 3 nanowires with a diameter of approximately 2 nm uniformly anchored on a cross-linked graphene ribbon network are fabricated. The unique three-dimensional structure can effectively improve the electrical conductivity and facilitate ion diffusion, especially cross-plane diffusion. Moreover, Fe 2 O 3 nanowires on graphene ribbons (Fe 2 O 3 /GR) are easily accessible for lithium ions compared with the traditional graphene sheets (Fe 2 O 3 /GS). In addition, the well-developed elastic network can not only undergo the drastic volume expansion during repetitive cycling, but also protect the bulk electrode from further pulverization. As a result, the Fe 2 O 3 /GR hybrid exhibits high rate and long cycle life Li storage performance (632 mAh g -1 at 5 A g -1 , and 471 mAh g -1 capacity maintained even after 3000 cycles). Especially at high mass loading (≈4 mg cm -2 ), the Fe 2 O 3 /GR can still deliver higher reversible capacity (223 mAh g -1 even at 2 A g -1 ) compared with the Fe 2 O 3 /GS (37 mAh g -1 ) for LIBs., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, we put forward a facile yet efficient room-temperature synthetic methodology for the smart fabrication of mesoporous nanocrystalline ZnMn2O4 in macro-quality from the birnessite-type MnO2 phase. A plausible reduction/ion exchange/re-crystallization mechanism is tentatively proposed herein for the scalable synthesis of the spinel phase ZnMn2O4. When utilized as a high-performance anode for advanced Li-ion battery (LIB) application, the as-synthesized nanocrystalline ZnMn2O4 delivered an excellent discharge capacity of approximately 1288 mAh g(-1) on the first cycle at a current density of 400 mA g(-1), and exhibited an outstanding cycling durability, rate capability, and coulombic efficiency, benefiting from its mesoporous and nanoscale structure, which strongly highlighted its great potential in next-generation LIBs. Furthermore, the strategy developed here is very simple and of great importance for large-scale industrial production., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)