Rocking-chair ammonium ion battery with high rate and long-cycle life

Aqueous rechargeable ammonium-ion batteries(AIBs)have drew considerable attention because of their capacity for high rates,low cost,and high safety.However,developing desired electrodes requiring stable structure in the aqueous fast ammoniation/de-ammoniation becomes urgent.Herein,an ammonium ion full battery using Cu_(3)[Fe(CN)_(6)]_(2)(CuHCF)acting to be a cathode and barium vanadate(BVO)acting to be an anode is described.Its excellent electrochemical behavior of Prussian blue analogs and the perfectly matched lattice structure of NH_(4)^(+)is expected.And the open structure of vanadium compounds satisfies the fast ammoniation/de-ammoniation of NH4+is also achieved.As a result of these synergistic effects,the BVO//CuHCF full cell retains 80.5 percent of its capacity following 1000 cycling.These achievements provide new ideas for developing low-cost and long-life AIBs.

Highly robust zinc metal anode directed by organic–inorganic synergistic interfaces for wearable aqueous zinc battery

Flexible aqueous zinc batteries(FAZBs)with high safety and environmental friendliness are promising smart power sources for smart wearable electronics.However,the bare zinc anode usually suffers from damnable dendrite growth and rampant side reaction on the surface,greatly impeding practical applications in FAZBs.Herein,a composite polymer interface layer is artificially self‐assembled on the surface of the zinc anode by graft‐modified fluorinated monomer(polyacrylic acid‐2‐(Trifluoromethyl)propenoic acid,PAA‐TFPA),on which an organic–inorganic hybrid(PAA‐Zn/ZnF2)solid electrolyte interface(SEI)with excellent ionic conductivity is formed by interacting with Zn2+.Both the pouch cell and fiber zinc anode exhibit excellent plating/stripping reversibility after protecting by this organic–inorganic SEI,which can be stably cycled more than 3000 h in symmetric Zn||Zn cells or 550 h in fiber Zn||Zn cells.Additionally,this interface layer preserves zinc anode with excellent mechanical durability under various mechanical deformation(stably working for another 1200 h after bending 100 h).The corresponding PAA‐Zn/ZnF2@Zn||MnO2 full cell displays an ultra‐long life span(79%capacity retention after 3000 cycles)and mechanical robustness(85%of the initial capacity for another 3000 cycles after bending 100 times).More importantly,the as‐assembled cells can easily power smart wearable devices to monitor the user's health condition.

金属有机框架衍生的氮掺杂碳包覆空心管In_(2)O_(3)/CdZnS异质结用于高效光催化析氢

光催化析氢(PHE)技术是解决当前能源短缺问题的有力途径之一.本文采用简单的油浴加热方法原位合成了六方空心管状氮掺杂碳包覆的In_(2)O_(3)/CdZnS异质结光催化剂.结果表明,N-C/In_(2)O_(3)/CdZnS(~22.87μmol h-1)的光催化析氢速率是原始CdZnS(~9.49μmol h-1)的~2.4倍,是原始In_(2)O_(3)(~0.42μmol h-1)的~54.5倍.经过4个循环后,光催化析氢量仍能达到原来的90%以上.其优异的光催化性能主要归功于以下几个方面:(1)氮掺杂碳层作为电子传输桥梁,保证了光催化反应的高效电子转移;(2)中空管状结构增强了光的反射,增强了光吸收性能;(3)形成N-C/In_(2)O_(3)/CdZnS异质结构,改善了载流子复合和光腐蚀问题;(4)大的比表面积和介孔结构提供了大量的反应位点.因此,本研究为设计可见光型异质结催化剂提供了新思路.

耦合无枝晶锌负极和可逆脱嵌钙离子的磷酸钒钠正极实现先进钙锌混合离子电池

混合离子电池综合了单一离子电池的优点,为开发高性能二次电池提供了新的见解.本文合成了一种有无定形活性碳和还原氧化石墨烯包覆的NASICON型正极材料(NVP@AC@rGO)用于钙离子的可逆脱嵌,并组装了一种与锌金属负极和水系混合电解质耦合的Ca/Zn离子混合电池.这种完美的结合不仅充分发挥了钙离子在NASICON结构中优异的扩散动力学,而且巧妙利用钙离子的低还原电位,形成静电屏蔽效应,从而抑制了锌枝晶的形成.因此,该混合电池具有超高的比容量,出色的倍率性能以及循环稳定性.这种巧妙的组合平衡了单一多价离子电池的优缺点,为设计高性能的水性多价离子电池提供了一种新的可行途径.

Amorphous nickel borate nanosheets as cathode material with high capacity and better cycling performance for zinc ion battery

Zinc-ion batteries are under current research focus because of their uniqueness in low cost and high safety.However,the pursuing of high-performance cathode materials of aqueous Zinc ion batteries(AZBs)with low cost,high energy density and long cycle life has become the key problem to be solved.Herein we synthesized a series of amorphous nickel borate(AM-NiBO)nanosheets by varying corrosion time with in-situ electrochemical corrosion method.The AM-NiBO-T13 as electrode material possesses a high areal capacity of 0.65 m Ah/cm^(2) with the capacity retention of 95.1%after 2000 cycles.In addition,the assembled AM-NiBO-T13//Zn provides high energy density(0.77 m Wh/cm^(2) at 1.76 m W/cm^(2)).The high areal capacity and better cycling performance can be owing to the amorphous nanosheets structure and the stable coordination characteristics of boron and oxygen in borate materials.It shows that amorphous nickel borate nanosheets have great prospects in the field of energy storage.

Defect engineering in Co-doped Ni_(3)S_(2) nanosheets as cathode for high-performance aqueous zinc ion battery

With the merits of low cost,environmental benignity,and high safety,aqueous zinc ion batteries(AZIBs)have great potential in the field of energy storage.In this paper,we craft a Co-doped Ni3 S2 with abundant sulfur vacancies as effective cathode materials(Co-Ni_(3) S_(2-x)) for AZIBs by hydrothermal and chemical reduction method.Notably,cobalt doping and abundant sulfur vacancies can effectively increase the conductivity and the number of active sites for electrochemical reactions,which gives the Co-Ni_(3) S_(2-x) electrode the outstanding capability to energy storage.By coupling Co-Ni_(3) S_(2-x) cathode with Zn anodes to assemble alkaline AZIBs,the Co-Ni_(3) S_(2-x)//Zn full battery exhibits excellent specific capacity(183.9 mAh g^(-1) at 1 A g^(-1),based on cathode mass) and extraordinary cycling durability(72.9% capacity retention after 6000 cycles).First-principles calculations based on density functional theory(DFT) confirm that the Co-Ni_(3) S_(2-x) electrode has strong energy storage capacity and electrochemical stability.The results provide an extremely significant reference in designs of self-supported bimetallic sulfide nanosheets,which have promising applications in high-performance energy storage devices.

Amorphous Ni-Co-S nanocages assembled with nanosheet arrays as cathode for high-performance zinc ion battery

The selection and development of cathode of alkaline zinc batteries(AZBs)is still hindered and often leads to poor rate capability and short cycle life.Here,amorphous hollow nickel-cobalt-based sulfides nanocages with nanosheet arrays(AM-NCS)are designed and constructed with ZIF-67 as the selftemplate to exchange with Ni^(2+) and S^(2-) by using a two-step ion exchange method.The synthesized AM-NCS possess the high specific capacity(160 m Ah/g at 2 A/g),and the assembled battery has excellent rate performance(146 m Ah/g reversible capacity at 5 A/g).The assembled device has excellent rate performance(155 m Ah/g at 2 A/g)and long cycling stability(7000 cycles,62.5%of initial capacity).The excellent electrochemical properties of the electrode materials are mainly attributed to the unique structure,in particular,polyhedron structure with hollow structure can improve the cyclic stability,and the amorphous structure can expose more reactive sites on the surfaces of nickel,cobalt and sulfur.This work provides a new strategy for the design and fabrication of high performance cathode materials for AZBs.