Toward High Capacity and Stable SnO_(2)Hollow Nanosphere Electrode Materials:A Case Study of Ni-substituted Modification

To develop the urgent requirement for high-rate electrodes in next-generation lithium-ion batteries,SnO_(2)-based negative materials have been spotlighted as potential alternatives.However,the intrinsic problems,such as conspicuous volume variation and unremarkable conductivity,make the rate capability behave badly at a high-current density.Here,to solve these issues,this work demonstrate a new and facile strategy for synergistically enhancing their cyclic stability by combining the advantages of Ni doping and the fabrication of hollow nanosphere.Specifically,the incorporation of Ni^(2+)ions into the tetragonal rutile-type SnO_(2)shellsimproves the charge transfer kinetics effectively,leading to an excellent cycling stability.In addition,the growth of surface grains on the hollow nanospheres are restrained after Ni doping,which also reduces theunexpected polarization of negative electrodes.As a result,the as-prepared Ni doped electrode delivers a remarkable reversible capacity of 712 mAh g^(-1)at 0.1 A g^(-1)and exhibits outstanding capacity of 340 mAh g^(-1)at 1.6 A g^(-1),about 2.58 times higher than that of the pure SnO_(2)hollow sample.

Liquid metal as an efficient protective layer for lithium metal anodes in all-solid-state batteries

Lithium metal batteries with inorganic solid-state electrolytes have emerged as strong and attractive candidates for electrochemical energy storage devices because of their high-energy content and safety.Nonetheless,inherent challenges of deleterious lithium dendrite growth and poor interfacial stability hinder their commercial application.Herein,we report a liquid metal-coated lithium metal(LM@Li)anode strategy to improve the contact between lithium metal and a Li6PS5Cl inorganic electrolyte.The LM@Li symmetric cell shows over 1000 h of stable lithium plating/stripping cycles at 2mA cm^(-2) and a significantly higher critical current density of 9.8 mAcm^(-2) at 25°C.In addition,a full battery assembled with a high-capacity composite LiNbO3@-LiNi_(0.7)Co_(0.2)Mn_(0.1)O_(2)(LNO@NCM721)cathode shows stable cycling performance.Experimental and computational results have demonstrated that dendrite growth tolerance and physical contact in solid-state batteries can be reinforced by using LM interlayers for interfacial modification.

Understanding oxygen vacant hollow structure CeO_(2)@In_(2)O_(3) heterojunction to promote CO_(2) reduction

In order to reduce the impact of greenhouse gases,we have studied a new and efficient photocatalyst to reduce CO_(2).We recombined the hollow CeO_(2) with the In_(2)O_(3) and introduced the oxygen vacancy to obtain the CeO_(2)@In_(2)O_(3) for the hollow structure of the oxygen vacancy.The test results show that CeO_(2)@In_(2)O_(3) with oxygen vacancy hollow structure(hereinafter collectively referred to as H-CeO_(2),H-In_(2)O_(3),and H-CeO_(2-x)@In_(2)O_(3-x))have higher photocatalytic reduction activity of CO_(2) than hollow CeO_(2) and hollow In_(2)O_(3).When the illumination time was 4 h,the yields of carbon dioxide reduction to CO and methane were 38.7 and 7.8 μmol·g^(-1),respectively.Consequently,we explained the photocatalytic reduction mechanism,and carried out the X-ray diffraction(XRD)and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) analysis of H-CeO_(2),H-In_(2)O_(3),and H-CeO_(2-x)@In_(2)O_(3-x).This study summarizes some experience for the study of oxygen vacancy hollow structure photocatalyst,and provides some new ideas in the field of photocatalytic reduction of CO_(2).