A highly stable zinc anode protected by a corrosion inhibitor for seawater-based zinc-ion batteries

The island-based energy storage is of urgent need for the grid construction combined with renewable energy for offshore operation.The direct use of seawater as a substitute of deionized water shows its great promise for aqueous zinc-ion batteries in such a specific situation.However,the metal corrosion,dendrite growth,and hydrogen evolution stand out in the harsh seawater environment.To address these challenges,we proposed a corrosion inhibitor that was effective in the field of metal anti-corrosion,2-phosphonobutane-1,2,4-tricarboxylic acid(PBTCA),to inhibit anode corrosion caused by Cl-and active H_(2)O molecules by forming a stable solid electrolyte interphase(SEI)film in the seawater-based electrolyte.Besides,PBTCA can chelate with other cations present in seawater,such as Ca^(2+)and Mg^(2+),thereby preventing the aggregation and precipitation of sparingly soluble species.Under a current density of5 mA cm^(-2),the seawater-based zinc-ion battery exhibited an exceptional cycle life exceeding 2000 h and maintained a Coulombic efficiency of over 99.6%after 2000 cycles.Additionally,the performance of the Zn||ZVO full battery was significantly enhanced with the addition of PBTCA.This study provides a simple,low-cost,and efficient approach for making the seawater-based zinc-ion batteries useable.

Enhanced chemical trapping and catalytic conversion of polysulfides by diatomite/MXene hybrid interlayer for stable Li-S batteries

Lithium-Sulfur (Li-S) batteries with high theoretical energy density are promising energy storage systems in the next decades, while the lithium polysulfides (LiPSs) shuttling caused by the sluggish sulfur redox reaction severely lowers the practical performance. The use of interlayer between the cathode and separator has been widely investigated to physically or chemically block the LiPSs, while the introduction of catalytic materials is a more effective strategy to accelerate the conversion of LiPSs. MXene with rich surface chemistry has shown its potential for facilitating the catalytic conversion, however, the aggregation of MXene sheets usually leads to the loss of the catalytic active sites. Herein, we report a diatomite/MXene (DE/MX) hybrid material as the bifunctional interlayer for improving the adsorption/conversion of LiPSs in Li-S batteries. The diatomite with porous structure and rich silica-hydroxyl functional groups could trap LiPSs effectively, while prevent the aggregation of MXene. The DE/MX based interlayer showed bifunctions of enhancing the chemical adsorption and promoting the conversion of LiPSs. The Li-S batteries with the DE/MX interlayer delivered an improved cycling stability with a low capacity decay of 0.059% per cycle over 1000 cycles at 1.0 C. Moreover, stable 200 cycles can be realized with a high sulfur loading electrode up to 6.0 mg cm^(−2). This work provides an effective strategy to construct bifunctional interlayers for hindering the shuttling of LiPSs and boosting the practical application of Li-S batteries.

IHVFL: a privacy-enhanced intention-hiding vertical federated learning framework for medical data

Vertical Federated Learning(VFL)has many applications in the field of smart healthcare with excellent performance.However,current VFL systems usually primarily focus on the privacy protection during model training,while the preparation of training data receives little attention.In real-world applications,like smart healthcare,the process of the training data preparation may involve some participant's intention which could be privacy information for this partici-pant.To protect the privacy of the model training intention,we describe the idea of Intention-Hiding Vertical Feder-ated Learning(IHVFL)and illustrate a framework to achieve this privacy-preserving goal.First,we construct two secure screening protocols to enhance the privacy protection in feature engineering.Second,we implement the work of sample alignment bases on a novel private set intersection protocol.Finally,we use the logistic regression algorithm to demonstrate the process of IHVFL.Experiments show that our model can perform better efficiency(less than 5min)and accuracy(97%)on Breast Cancer medical dataset while maintaining the intention-hiding goal.

Comparative techno-economic analysis of large-scale renewable energy storage technologies

Energy storage is an effective way to address the instability of renewable energy generation modes,such as wind and solar,which are projected to play an important role in the sustainable and low-carbon society.Economics and carbon emissions are important indicators that should be thoroughly considered for evaluating the feasibility of energy storage technologies(ESTs).In this study,we study two promising routes for large-scale renewable energy storage,electrochemical energy storage(EES)and hydrogen energy storage(HES),via technical analysis of the ESTs.The levelized cost of storage(LCOS),carbon emissions and uncertainty assessments for EESs and HESs over the life cycle are conducted with full consideration of the critical links for these routes.In order to reduce the evaluation error,we use the Monte Carlo method to derive a large number of data for estimating the economy and carbon emission level of ESTs based on the collected data.The results show that lithium ion(Li-ion)batteries show the lowest LCOS and carbon emissions,at 0.314 US$kWh-1 and 72.76 g CO_(2) e kWh^(-1),compared with other batteries for EES.Different HES routes,meaning different combinations of hydrogen production,delivery and refueling methods,show substantial differences in economics,and the lowest LCOS and carbon emissions,at 0.227 US$kWh^(-1) and 61.63 gCO_(2) e kWh^(-1),are achieved using HES routes that involve hydrogen production by alkaline electrolyzer(AE),delivery by hydrogen pipeline and corresponding refueling.The findings of this study suggest that HES and EES have comparable levels of economics and carbon emissions that should be both considered for large-scale renewable energy storage to achieve future decarbonization goals.

电子轴向拉伸提升贫氧环境海水电池性能

长寿命溶解氧海水电池是深远海观测能源网络的重要组成单元,但海水贫氧复杂环境对设计高性能氧还原催化剂提出了重要挑战.本文以酞菁铁为模型催化剂,通过理论计算与实验验证,提出了活性位点电子轴向拉伸可大幅提升催化剂在极端贫氧环境中的氧还原活性和稳定性.该研究为构建高性能海水电池提供了材料学解决方案,同时为极端环境下催化剂的变革性设计提供了新的思路.

Capillary shrinkage of graphene oxide hydrogels

Conventional carbon materials cannot combine high density and high porosity,which are required in many applications,typically for energy storage under a limited space.A novel highly dense yet porous carbon has previously been produced from a three-dimensional(3D)reduced graphene oxide(r-GO)hydrogel by evaporation-induced drying.Here the mechanism of such a network shrinkage in r-GO hydrogel is specifically illustrated by the use of water and 1,4-dioxane,which have a sole difference in surface tension.As a result,the surface tension of the evaporating solvent determines the capillary forces in the nanochannels,which causes shrinkage of the r-GO network.More promisingly,the selection of a solvent with a known surface tension can precisely tune the microstructure associated with the density and porosity of the resulting porous carbon,rendering the porous carbon materials great potential in practical devices with high volumetric performance.

Demystifying the catalysis in lithium–sulfur batteries:Characterizationmethods and techniques

Lithium–sulfur(Li-S)batteries are promising next-generation energy storage systems with ultrahigh energy density.However,the intrinsic sluggish“solid–liquid–solid”reaction between S8 and Li2S causes unavoidable shuttling of polysulfides,severely limiting the practical energy density and cycling performance.Recently,the catalysis process has been introduced for the sulfur redox reaction to accelerate the conversion of polysulfides,providing a positive remedy for the polysulfides shuttling.Nevertheless,in-depth understanding of the catalyst evaluation criteria and catalytic mechanism still lies in the“black box”,and precise characterization technique is the key to unlock this puzzle.In this review,we provide a comprehensive overview of characterization techniques on the catalyst in Li-S batteries from two aspects of catalytic performance and catalytic mechanism,highlighting their significance and calling for more efforts to develop precise and fast techniques for Li-S catalysis.Moreover,we envision the future development of characterization for better understanding the catalysis toward practical Li-S battery.