Constructing ultrastable electrode/electrolyte interface for rapid potassium ion storage capability via salt chemistry and interfacial engineering

Conversion/alloying anode materials exhibiting high K storage capacities suffer from large volume variations and unstable electrode/electrolyte interfaces upon cycling.Herein,taking SnS/reduced graphene oxide(SnS/rGO)anodes as an example,the electrochemical performance of SnS/rGO could significantly be improved via employing potassium bis(fluorosulfonyl)imide(KFSI)salt in electrolytes and ultrathin TiO_(2) coating.KF-rich inorganic layer was demonstrated to help form robust SEI layer,which could suppress the side reactions to increase the Coulombic efficiency.The formed potassiated K_(x)TiO_(2) coating layer was constructed to boost charge transfer capability and K-ion diffusion kinetics.The as-prepared SnS/rGO@TiO_(2)-20 electrode in KFSI electrolyte delivers the high CE of 99.1%and 424 mAh·g^(−1) after 200 cycles with an ultrahigh capacity retention of 98.5%.

A PROPOSAL FOR DEVELOPING CHEMISTRY AND CHEMICAL ENGINEERING OF CHINA'S SALT LAKES

The author puts forward a proposal for developing chemistry and chemical engineering of China’s salt lakes on the basis of an investigation into exploitation and utilization of salt lake resources all over the world. It contains the subjects of setting up an engineering research center, mainly developing leading products, giving priority to the development of a chemical industry by using Qinghai salt lake resources, actively popularizing results, stressing basic research and systematic management.

Electrochemical codeposition of typical α+β phases Mg-Li alloys from the molten LiCl-KCl-MgCl_2 system

Electrochemical codeposition of Mg-Li alloys on molybdenum electrodes was investigated in LiCl-KCl（50 wt.%：50 wt.%） melts containing different concentrations of MgCl2 at 973 K.Cyclic voltammograms show that the underpotential deposition of lithium on pre-deposited magnesium leads to the formation of liquid Mg-Li alloys.The deposition potentials of Mg（II） and Li（I） ions gradually near each other with MgCl2 concentration decreasing.Mg-Li alloys with typical α ＋ β phases could be obtained by potentiostatic electrolysis from LiCl-KCl melts containing 5 wt.% MgCl2 at -2.25 V vs.Ag/AgCl（cathodic current density 1.70 A·cm-2） for 2.5 h.α phase, α ＋ β phases, and β phase Mg-Li alloys with different lithium contents were obtained by potentiostatic electrolysis from LiCl-KCl melts with the different concentrations of MgCl2.The samples were characterized by X-ray diffraction and scanning electron microscopy.

Modeling heterogeneous chemical processes on aerosol surface

To explore the possible impact of heterogeneous chemical processes on atmospheric trace components, a coupled box model including gas-phase chemical processes, aerosol thermodynamic equilibrium processes, and heterogeneous chemical processes on the surface of dust, black carbon （BC） and sea salt is set up to simulate the effects of heterogeneous chemistry on the aerosol surface, and analyze the primary factors affecting the heterogeneous processes. Results indicate that heterogeneous chemical processes on the aerosol surface in the atmosphere will affect the concentrations of trace gases such as H2O2, HO2, O3, NO2, NO3, HNO3 and SO2, and aerosols such as SO42-, NO3- and NH4＋. Sensitivity tests suggest that the magnitude of the impact of heterogeneous processes strongly depends on aerosol concentration and the surface uptake coefficients used in the box model. However, the impact of temperature on heterogeneous chemical processes is considerably less. The ＂renoxification＂ of HNO3 will affect the components of the troPosPhere such as nitrogen oxide and ozone.