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If the preferred growth planes are ( 105), (103), and (002), the crystal grows at an angle of 0-30° from the substrate. If the preferred growth planes are ( 101), ( 102), (112), and (114), the crystal grows at an angle of 30-70° from the substrate. And if the preferred growth planes are ( 100) and ( 110), the crystal grows at an angle of 70-90° from the substrate. [10] By density functional theory (DFT) calculation, Zhu et al. [11] revealed that the binding energies between Zn atom and the (002), (100), and (101) planes of Zn metal are different. The binding energy of (002) plane is the weakest, while that of (101) plane is the strongest, which means that Zn atoms will preferentially deposit on that crystal plane, allowing (101) plane to preferentially grow, and thus resulting in the formation of Zn dendrites. If crystal planes like (105), (103), and (002) can be induced to preferentially grow, it will make deposition layer smoother and inhibit the formation of Zn dendrites. It is worth noting that the preferential growth of ( 105), (103), and (002) planes can form a compact deposition layer to inhibit corrosion and H 2 evolution to a certain extent. [12,13] Therefore, reasonable manipulation of crystal orientation is of great significance for AZIBs.Up to now, the methods of manipulating crystal orientation in AZIBs mainly include optimizing the separator, [14,15] modifying coating layers, [16][17][18][19][20][21][22] using electrolyte additives, [11,[23][24][25][26][27][28] and processing/heating treatment of the Zn anode. [12,13,29] In the above methods, using electrolyte additives is much attractive because of its convenience and cost-effectiveness. [30][31][32] Electrolyte additives such as Mn 2+ +gelatin, SBT, OTf 2− , H 3 PO 4 , In 2 (SO 4 ) 3 , H 3 BO 3 , CTAB, SDS, TU, and PEG-8000 have been employed to induce preferential growth of specific crystal planes. [11,[23][24][25][26][27][28] Nevertheless, most of these researches require pre-preparation of Zn anodes with specific crystal planes such as (002), [11,[25][26][27][28] which makes the process complicated. And most works only focused on the orientation change of Zn crystals after a single electrodeposition. It is worth noting that almost all of these works were unable to maintain a long cycle life under the condition of high current density and large areal capacity, which may be related to the weakened effect of electrolyte additives due to the structural reconstruction of Zn anode over cycling. [11] Therefore, it is crucial to systematically Uncontrolled growth of Zn dendrites is the main reason for the short-circuit failure of aqueous Zn-ion batteries. Using electrolyte additives to manipulate the crystal growth is one of the most convenient strategies to mitigate the dendrite issue. However, most additives would be unstable during cycling due to the structural reconstruction of the deposition layer. Herein, it is proposed to use 1-butyl-3-methylimidazolium cation (BMIm + ion) as an electrolyte additive, which could steadily induce the preferential ...

It is a tough issue to achieve high electrochemical performance and high sulfur loading simultaneously, which is of important significance for practical Li–S batteries applications. Inspired by the transportation system of the plant root in nature, a biomimetic root-like carbon/titanium nitride (TiN/C) composite nanofiber is designed as a freestanding current collector for the high sulfur loading cathode. Like the plant root which absorbs water and oxygen from soil and transfers them to the trunk and branches, the root-like TiN/C matrix provides high-efficiency polysulfide, electron, and electrolyte transfer for the redox reactions via its three-dimensional-porous interconnected structure. In the meantime, TiN can not only anchor the polysulfides via the polar Ti–S and N–S bond but also further facilitate the redox reaction because of its high catalytic effect. With 4 mg cm–2 sulfur loading, the TiN/C@S cathode delivers a high initial discharge capacity of 983 mA h g–1 at 0.2 C current density; after 300 charge/discharge cycles, the discharge capacity remains 685 mA h g–1, corresponding to a capacity decay rate of ∼0.1%. Even when the sulfur loading is increased to 10.5 mg cm–2, the cell still delivers a high capacity of 790 mA h g–1 and a decent cycle life. We believe that this novel biomimetic root-like structure can provide some inspiration for the rational structure design of the high-energy lithium–sulfur batteries and other composite electrode materials.

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Lithium-sulfur (Li-S) batteries are competitive for the next-generation energy storage applications. However, soluble polysulfides cause severe shuttle effect and electrolyte abuse. Solid-solid and quasi-solid conversions are effective to address the...