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Aqueous zinc ion batteries (AZIBs) show great prospects in large‐scale energy storage applications, whereas this technology suffers from the lack of cathode materials with high capacity and stability. Here, a cathode material of SbO2 nanoparticles decorated onto the surface of K0.43V6O13 nanobelt is presented. The SbO2 is disclosed as proton‐phile and zinc‐phobic, which thus favors H+ intercalation. In consequence, the increase of H+ intercalation can offset the lattice shrinkage caused by Zn2+ intercalation, and contribute to excellent cyclic stability of the battery. Finally, SbO2/K0.43V6O13 delivers a reversible capacity of 414.2 mAh g−1 at 1 A g−1 after 1000 cycles with a retention of 103%, and 223.5 mAh g−1 at 20 A g−1 after 20 000 cycles with a retention of 89.3%, showing long cycling life at both low current and high current densities. This study provides new insights into the effecting factors for the performance of AZIBs cathode and an effective strategy to improve its stability. [ABSTRACT FROM AUTHOR]

Antimony selenosulfide, Sb2(S,Se)3, has been considered as new‐generation light‐harvesting material for high‐efficiency photovoltaic applications due to its adjustable bandgap, high absorption coefficient, and excellent stability. In terms of device operation, the electron transfer from the electron transporting layer to Sb2(S,Se)3 layer plays a critical role in improving the photovoltaic energy conversion efficiency of solar devices. Intricately manipulating the surface and interface properties has been a great challenge in solar cell fabrications. Herein, an effective approach toward the reconstruction of the CdS interfacial layer, and the following Sb2(S,Se)3 absorber film by utilizing polar ethylenediamine (EDA) solvent annealing at room temperature is developed. It is found that the presence of nitrogen‐containing functional groups of EDA on the CdS surface not only promotes the grain growth and crystallization of CdS, but also induces optimized deposition of Sb2(S,Se)3 films in terms of interfacial contact and defect formation. Finally, the Sb2(S,Se)3 solar cell based on EDA–CdS achieves a top efficiency of 10.10%. This study provides an efficient method and a new understanding of chemically healing inorganic thin films. [ABSTRACT FROM AUTHOR]

Red phosphorus shows great promise as a high‐capacity anode material for Na batteries. Such electrodes that suffered from the fracturing impact of volume change during cycling can be effectively improved by 1D nanomaterials. However, the synthesis of 1D red phosphorus has rarely been studied and employed in sodium batteries. Here, a simple selenium‐induced method to generate fibrous nano red phosphorus is presented. It turns out that a small amount of selenium can not only induce high‐quality fibrous nano red phosphorus from commercial red phosphorus, but also benefit qualitatively to the sodium ionic conductivity. Interestingly, the selenium dopant can also manipulate the chemical state of phosphorus leading to valence tunability which is able to tolerate structural stability under the Na‐rich or Na‐poor condition. As a result, the optimal fibrous nano red phosphorus used as anode outperforms over the traditional red phosphorus ≈6 and ≈10 times in terms of rate performance and cycle stability, respectively. Furthermore, as employed for sodium metal anode protection, the symmetrical cell cycling maintains long stable at a low polarization voltage for over 1000 h. The full cell performs excellent cycling stability of 1500 cycles at 3 C and high‐rate performance up to 30 C. [ABSTRACT FROM AUTHOR]

Sodium (Na) metal has been considered as the most promising anode for achieving next‐generation battery system with high energy density and low cost. Nevertheless, the uncontrolled dendrites growth, infinite volume expansion and unstable solid/electrolyte interphase severely hinder the practical application of Na metal anode. Herein, a functional composite Na anode (Na2Se/Cu@Na) is achieved via infusing molten Na into the porous copper framework modified by cuprous selenide nanosheets. Combining experimental studies and theoretical calculations, the 3D framework and derivatives of Na2Se/Cu can synergistically buffer the volume expansion, redistribute Na+ flux, promote ions migration, and induce uniform Na+ deposition. Benefiting from these merits, the symmetrical cell of Na2Se/Cu@Na demonstrates a stable cycle lifespan over 500 h at 1 mA cm−2 in carbonate electrolyte. And the full battery paired with Na3V2(PO4)3 cathode delivers a stable capacity of 97 mAh g−1 after 800 cycles at 10 C. Furthermore, this structured framework can also be employed to construct composite potassium (K) anode and an outstanding cycle performance is achieved in the symmetrical cell (operating for 1000 h at 0.5 mA cm−2). This study paves a significant way of designing structured Na (K) metal anodes for synergistically improving the electrode stability. [ABSTRACT FROM AUTHOR]

Potassium–selenium (K‐Se) batteries have attracted increasing attention for their potential as stationary energy storage systems due to their high theoretical energy density and low cost. The major challenges of these batteries are the low utilization of active selenium, sluggish kinetics, and the volume change during cycling. Herein, a N and O dual‐doped porous carbon nanocage anchored with carbon nanotubes (CNTs) (denoted as NO‐nanocage/CNT) is designed as a host for Se. This material combines multiple advantages, such as abundant N/O active sites and excellent electrical conductivity, to realize highly efficient immobilization of Se and polyselenide and fast redox kinetics. The hollow carbon skeleton, with abundant micro and mesoporous structures, shortens the diffusion distances between the ions/electrons and accommodates the volume expansion of the active materials. Density functional theory calculations further confirm that the NO‐nanocage/CNT exhibits strong chemical affinity to K2Se, which is in agreement with the experimental results. The Se@NO‐nanocage/CNT cathode displays a remarkable reversible capacity (623 mAh g−1 at 0.1 A g−1) and an ultra‐long cycle life (274 mAh g−1 after 3500 cycles at 1.0 A g−1). The design presented in this paper offers a new approach for the design of multifunctional Se hosts for advanced alkali metal‐chalcogen batteries. [ABSTRACT FROM AUTHOR]

Constructing artificial solid‐electrolyte interphase (SEI) on the surface of Li metal is an effective approach to improve ionic conductivity of surface SEI and buffer Li dendrite growth of Li metal anode. However, constructing of homogenous ideal artificial SEI is still a great challenge. Here, a mixed lithium‐ion conductive Li2S/Li2Se (denoted as LSSe) protection layer, fabricated by a facile and inexpensive gas–solid reaction, is employed to construct stable surface SEI with high ionic conductivity. The Li2S/Li2Se‐protected Li metal (denoted as LSSe@Li) exhibits a stable dendrite‐free cycling behavior over 900 h with a high lithium stripping/plating capacity of 3 mAh cm−2 at 1.5 mA cm−2 in the symmetrical cell. Compared to bare Li anode, full batteries paired with LiFePO4, sulfur/carbon, and LiNi0.6Co0.2Mn0.2O2 cathodes all present better battery cycling and rate performance when LSSe@Li anode is used. Moreover, Li2Se exhibits a lower lithium‐ion migration energy barrier in comparison with Li2S which is proved by density functional theory calculation. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries with potentially high specific energy are viewed as very promising candidates for next‐generation lightweight and low‐cost rechargeable batteries. However, sulfur‐based cathodes suffer from dissolution of polysulfides causing shuttle effects. Here, in order to confine elemental sulfur and anchor the polysulfides, a novel host that is an inexpensive natural clay mineral, viz., vermiculite is proposed. When compared to regular carbon–sulfur composites, vermiculite–sulfur composites offer promising rate capability and much better cycling stabilities, displaying capacity retentions of ≈89 and ≈93% within 200 cycles at C/2 and 1 C, respectively, and ≈60 % at C/5 within 1000 cycles. Postmortem studies, advanced adsorption tests, density functional theory calculations, and zeta potential measurements in combination with intrinsic characteristics of the natural vermiculite provide insights into the new mechanism. The vermiculite contains naturally present surface cations which show a strong tendency to adsorb Sn2− anions, hence protecting them from dissolution. The excess surface charge is most probably compensated by excess Li+ in the space charge zones which is beneficial for charge transfer and local conductivity. The reported results show that natural clay‐minerals are promising sulfur hosts being able to fixate sulfides via electrical double layer effects, thus enabling high‐performance in lithium–chalcogen batteries. [ABSTRACT FROM AUTHOR]

The organic–inorganic halide CH3NH3PbI3 (MAPbI3) has been the most commonly used light absorber layer of perovskite solar cells (PSCs); however, solution‐processed MAPbI3 films usually suffer from random crystal orientation and high trap density, resulting in inferior power conversion efficiency (PCE) with open circuit voltage (Voc) being typically below 1.2 V for PSC devices. Herein, for the first time an imidazole sulfonate zwitterion, 4‐(1H‐imidazol‐3‐ium‐3‐yl)butane‐1‐sulfonate (IMS), is applied as a bifunctional additive in regular‐structure planar heterojunction PSC devices to regulate the crystal orientation, yielding highly ordered MAPbI3 film and passivating the trap states of the film. Such a dual effect of IMS is fulfilled via coordination interactions between the sulfonate moiety of IMS with the Pb2+ ion and the electrostatic interaction between the imidazole of IMS with the I– ion of MAPbI3. As a result, under a optimized IMS doping ratio of 0.5 wt%, the PSC device exhibits a significant increase in PCE from 18.77% to 20.84%, with suppressed current–voltage hysteresis and promoted ambient stability. Moreover, a high Voc of 1.208 V is achieved under a higher IMS doping ratio of 1.2 wt%, which is the highest Voc for regular‐structure MAPbI3 planar PSC devices based on TiO2 electron transport layer. [ABSTRACT FROM AUTHOR]