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Suppressing the water activity is challenging to achieve high‐performing aqueous zinc ion batteries (AZIBs), especially for its practical climate adaptability. Reconstructing the H‐bond network and repealing the solvation water can effectively reinforce the covalency inside water molecular. Here, a hydrogel electrolyte formula utilizing ClO4− anions and hydrophilic ─NH2 on polyacrylamide chains is shown to bond with water molecules, while the zincophilic glucose preferentially regulate Zn2+ solvation. The multifunctional hydrogel structure can effectively disrupt the intrinsic H‐bond network and inhibit the interface side‐reactions induced by active water. Finally, the delayed freezing point and expanded voltage stability window are realized, which promotes the ZIBs steady operate in a wide temperature range. When operating at 70 and −30 ˚C, the Zn//NVO battery achieves high specific capacity of 488 and 254 mAh g−1, respectively, surpassing most of the previously reported results. Remarkably, the pouch battery delivers the state‐of‐the‐art specific capacity of 438.1 mAh g−1 and realizes a capacity retention of 76.3% after 400 cycles at 200 mA g−1. [ABSTRACT FROM AUTHOR]

The solution processed FAPbI3 perovskite usually suffers from chaotic orientations. Herein, a template structure of oriented 2D perovskite is used to obtain a high-quality FAPbI3 film with (001) preferred orientation by cation exchange. The highly oriented BA2PbI4 serves as a growth template and promotes the (001) orientation of the 3D perovskite. The dominantly (001) orientated FAPbI3 perovskite exhibits uniform surface morphology and suppressed film defects. [ABSTRACT FROM AUTHOR]

Dendrite‐free Zn anode is the key to avoiding battery failure, which is largely determined by the crystal growth during the electrodeposition process. Therefore, controlling the specific crystal orientation growth of Zn is imperative for high‐performing aqueous zinc ion batteries. Herein, an electrocrystallization orientation regulation strategy is proposed to achieve near‐unity stacked Zn (002) texture growth. Featuring the zincophilic nature and high electronegative carboxylate radical, disodium maleate molecules tend to selectively adsorb on the Zn (002) crystal plane, forming a dynamic protection layer. This adsorption layer regulates Zn2+ diffusion along [100] and [101] orientations with the lowest deposition rate on the (002) plane, homogenizes Zn2+ flux, and keeps away water from Zn surface, constructing the flattened and horizontally arranged Zn deposition layer with dominantly Zn (002) texture and inhibited side‐reaction. Consequently, the Zn anode with near‐unity stacked (002) texture exhibits a 40‐fold enhancement in running lifetime beyond 3200 h and improved coulombic efficiency of 99.81% over 3000 cycles than that with bare ZnSO4 electrolyte. Even at harsh plating/stripping conditions of 30 and 30 mAh cm−2, the Zn anode still sustains state‐of‐the‐art stability over 120 h, enabling a substantial advance in the long‐term stability of the battery. [ABSTRACT FROM AUTHOR]

Realizing efficient FAPbI3-based devices with high open-circuit voltage (VOC) is still challenging, due to severe energy loss between the n-type perovskite and p-type hole-transporting layer (HTL). Here, we developed a strategy involving controlling the formation of iodine vacancies in order to induce formation of p-type perovskite and hence mitigate such energy loss. Post-deposition of n-butylamine iodide was discovered to induce an n-to-p-type transition in the FAPbI3 perovskite and hence form the p-type perovskite/p-type HTL junction. The resultant device realized a VOC of as high as 1.12 V, a value ∼14.3% higher than that of the corresponding n-type FAPbI3 device (0.98 V). [ABSTRACT FROM AUTHOR]

Reversibility, usually evaluated by Coulombic efficiency (CE) and limited by dendrite growth, has become the major roadblock toward the widespread commercialization of zincion batteries. Tailoring the Zn deposition behavior is vital to prevent dendrite growth. In this work, the facet‐terminator serine is introduced to modulate the interface and obstruct the rampant growth of the Zn (100) plane. The serine cation (Ser+) is revealed to preferentially adsorb onto the electrode/electrolyte interface, suppressing the interfacial parasitic reaction. Theoretical analysis and postmortem/operando experimental techniques indicate that the Ser+ bestows (100)‐dominated morphology to zinc anodes, enabling a highly reversible and dendrite‐free Zn anode. These features endow the Zn anode with a long cyclic life of more than 800 h for Zn//Zn batteries and a high average Coulombic efficiency of 99.8% at 5 mA cm−2 and 5 mAh cm−2 for Zn//Cu batteries. When assembling with commercial V2O5, the full battery delivers a high capacity of 345.1 mAh g−1 at 5 A g−1 with a retention of 74.1% over 2000 cycles. [ABSTRACT FROM AUTHOR]

Summary: The CsxFA1−xPbI3 perovskites are promising materials for photovoltaic applications owing to their high absorption coefficient and stability. However, the CsxFA1−xPbI3 films contain a high percentage of FA+ suffer from split phase and high trap states, leading to inferior photovoltaic performance. Hence, a template‐assisted technique basing on two‐stage intramolecular exchanges was developed to suppress phase separation as well as get desirable high quality CsxFA1−xPbI3 perovskite film. The as‐prepared colloidal CsI‐PbI2 film is treated with FAI solution before annealing. The obtained CsxFA1−xPbI3 perovskite thin layer displays a superb absorption edge beyond 830 nm and highly uniform enlarged grains with reduced grain boundaries or defects. Meanwhile, the improved morphology attributes to substantially increased photon‐induced electron‐hole pairs and corresponding collection efficiency which was testified by the external quantum efficiency measurements. The perovskite solar cells fabricated by this method presented power conversion efficiency of 18.5%. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid halide perovskites are unstable under ultraviolet (UV) irradiation. To solve this profound issue, an all-inorganic CsPbBr3 perovskite device is used as the top cell to overcome the ultraviolet light instability of the FAPbI3 photovoltaic device (bottom cell). The inorganic CsPbBr3 layer is prepared via an advanced nucleation process to decrease the Gibbs free energy, resulting in more nuclei as well as a dense layer. The prepared CsPbBr3 layer acts as a UV filter to avoid the problem of UV light instability on the bottom cell. When the dense CsPbBr3 layer acts as a top cell in the 4-terminal tandem device, the FAPbI3 based bottom cell exhibits excellent stability during the UV test. [ABSTRACT FROM AUTHOR]

Anatase TiO2 is a promising anode material for lithium‐ion batteries (LIBs) owing to its low cost and stability. However, the intrinsically kinetic limits seriously hindered its lithium‐ion storage capability. Here we present that anatase TiO2 with rich oxygen vacancies can enhance its lithium‐ion storage performance. We synthesize anatase TiO2 with well‐retained hierarchical structure by annealing the H2Ti5O11·3H2O yolk‐shell spheres precursor in nitrogen atmosphere. EPR and XPS data evidence that the oxygen‐deficient environment could generate abundant oxygen vacancies in the as‐derived anatase TiO2, which leads to improved electron conductivity and reduced charge‐transfer resistance. The rich oxygen vacancies and high structural integrity of the hierarchical yolk‐shell spheres enable the as‐derived anatase TiO2 yolk‐shell spheres with a high specific capacity of 280 mAh g−1 at 100 mA g−1 and 71% of capacity retention after 5000 cycles at 2 A g−1. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is a promising electrode material for reversible lithium storage. However, the poor electronic conductivity, sluggish diffusivity, and intrinsic kinetics limit hinder its fast lithium storage capability. Here we present that the oxygen‐deficient TiO2 hierarchical spheres can address the issues for high capacity, long‐term lithium‐ion battery anode. First‐principles calculations show that introducing oxygen vacancies to anatase TiO2 can reduce the bandgap, thus improving the electronic conductivity and further the lithium storage properties of TiO2. By annealing TiO2/H2Ti5O11⋅3H2O hierarchical spheres precursor in nitrogen, accompanying with the phase transfer process, the growth of TiO2 crystallites is restricted due to the generation of residual carbon species, resulting in a well maintained hierarchical spherical structure. Rich oxygen vacancies are generated in the oxygen‐deficient environment and evidenced by EPR, XPS, and UV‐Vis spectra, which enable the TiO2 hierarchical spheres reduced bandgap. The oxygen vacancies in the as‐obtained TiO2 hierarchical spheres together with the high structural integrity of the hierarchical spheres gives rise to superior lithium storage properties including a high specific capacity of 282 mAh g−1 at 200 mA g−1, and long‐term cycling stability with a capacity retention of 85.2 % at 4 A g−1 over 10000 cycles. [ABSTRACT FROM AUTHOR]