Copper Indium Sulfide Enables Li-CO_(2)Batteries with Boosted Reaction Kinetics and Cycling Stability

High energy density Li-CO_(2)batteries have attracted much attention owing to the"two birds with one stone"feature in fixing greenhouse gas CO_(2)and providing renewable energy.However,poor reversibility of the discharge product Li_(2)CO_(3)is one of the main problems that limit its application,resulting in poor cycling stability and severe polarization.Herein,copper indium sulfide(CIS),a semiconducting non-precious metal sulfide,is fabricated as cathode catalysts for high-performance Li-CO_(2)batteries.Combined with the synergistic effect of bimetallic valence bonding and coordinated electron transfer,Li-CO_(2)batteries using CIS cathodes exhibit high full specific discharge capacity,excellent rate capability and cycle stability,namely it delivers a high specific full discharge capacity of 8878μAh cm^(-2),runs steadily from 10 to 100μA cm^(-2),and performs a stable long-term cycling behavior(>1050 h)under a high energy efficiency of 84%and a low charge voltage of approximately 3.4 V at 20μA cm^(-2)within 100μAh cm^(-2).In addition,a flexible Li-CO_(2)pouch cell is constructed to reveal the potential of employing CIS to fabricate flexible high energy storage devices in practical applications.This work shows a promising development pathway toward next-generation sustainable energy storage devices.

Solvothermal Synthesis and Characterization of Zinc Indium Sulfide Microspheres

ZnIn2S4 microspheres have been solvothermally prepared at 160℃ for 12 h with ZnCl2.2H2O,InCl3,and thiourea as the starting reagents in ethanol.The morphology,structure,and phase composition of the asprepared product were characterized by means of X-ray powder diffraction（XRD）,field-emission scanning electron microscopy（FE-SEM）,X-ray photoelectron spectra（XPS）,transmission electron microscopy（TEM）,high-resolution TEM（HRTEM）,and selected area electron diffraction（SAED）.Results revealed that the prepared ZnIn2S4 microspheres were composed of sheetlike nanocrystals.The average diameter of the microspheres and the thickness of the nanosheets are about 1-6 μm and 10-50 nm,respectively.A possible growth mechanism of the ZnIn2S4 nanosheet-built microspheres was proposed and briefly discussed.

Template synthesis of silver indium sulfide based nanocrystals performed through cation exchange in organic and aqueous media

Heavy-metal-free silver based I-III-VI semiconductor nanocrystals(NCs),including ternary silver indium sulfide(AgInS_(2))and derivative quaternary silver indium zinc sulfide(i.e.,AgInZn_(2)S_(4))NCs,possess advantages of low toxicity,and size-tunable band gaps approaching near-infrared spectral range,which make them candidates for use in optoelectronic and biological devices.Herein,we report syntheses of AgInS_(2) based NCs starting from In_(2)S_(3) template,which have been performed both in organic and aqueous phase through cation exchange.As a result,ternary silver indium sulfide and quaternary silver indium zinc sulfide NCs are obtained in both organic and aqueous media,and confirmed to be orthorhombic AgInS_(2) NCs and hexagonal AgInZn_(2)S_(4) NCs,respectively.Furthermore,the aqueous AgInZn_(2)S_(4) NCs with red emission and low cytotoxicity are explored for the cancer cell imaging.

Rationally designed synthesis of bright AgInS2/ZnS quantum dots with emission control

In the blossoming field of Cd-free semiconductor quantum dots(QDs),ternary Ⅰ-Ⅲ-VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water,their high photoluminescence(PL)quantum yields(QYs)in the red and near infrared(NIR)region,and their inherently low toxicity.Moreover,their oxygen-insensitive long PL lifetimes of up to several hundreds of nanoseconds close a gap for applications exploiting the compound-specific parameter PL lifetime.To overcome the lack of reproducible synthetic methodologies and to enable a design-based control of their PL properties,we assessed and modelled the synthesis of high-quality MPA-capped AglnS2/ZnS(AlS/ZnS)QDs.Systematically refined parameters included reaction time,temperature,Ag:In ratio,S:In ratio,Zn:In ratio,MPA:ln ratio,and pH using a design-of-experiment approach.Guidance for the optimization was provided by mathematical models developed for the application-relevant PL parameters,maximum PL wavelength,QY,and PL lifetime as well as the elemental composition in terms of Ag:ln:Zn ratio.With these experimental data-based models,MPA:ln and Ag:ln ratios and pH values were identified as the most important synthesis parameters for PL control and an insight into the connection of these parameters could be gained.Subsequently,the experimental conditions to synthetize QDs with tunable emission and high QY were predicted.The excellent agreement between the predicted and experimentally found PL features confirmed the reliability of our methodology for the rational design of high quality AlS/ZnS QDs with defined PL features.This approach can be straightforwardly extended to other ternary and quaternary QDs and to doped QDs.

Breakdown of Valence Shell Electron Pair Repulsion Theory in an H-Bond-Stabilized Linear sp-Hybridized Sulfur

Exploring the unusual orbital hybridization types of atoms and their new connection modes contributes to the development of chemical bond theory and can inspire compounds with unique molecular configurations.Dicoordinated sulfur(S)atoms(or anions)with sp3 hybridization in a bent-bridging mode are commonly observed in many inorganic and organic compounds.However,sp-hybridized S species have,thus far,been extremely rare,and the linearly bridging mode has only been“forcibly”achieved with the aid of metal–S multiple bonds and/or significant steric hindrance from the surrounding organic ligands.