Because the reconstruction of catalysts is generally observed during oxidation reactions, understanding the intrinsic structure-related reconstruction ability of electrocatalysts is highly desirable but challenging. Herein, a controllable hydrolysis strategy is developed to obtain nickel hydroxide electrocatalysts with controllable nickel vacancy (V Ni ) concentrations, as confirmed by advanced spectroscopic characterization. Electrochemical measurements show that the reconstruction can be promoted with the increase of V Ni concentration to generate true active components, thereby boosting activities for both oxygen evolution reaction (OER) and urea oxidation reaction (UOR). Density functional theory calculations confirm that the increased V Ni concentration yields decreased formation energies of the true active components during reactions. This work provides fundamental understanding of the reconstruction ability of electrocatalysts in anodic oxidation reactions from the view of intrinsic defects.

All-solid-state lithium batteries (ASSLBs), which use solid electrolytes instead of liquid ones, have become a hot research topic due to their high energy and power density, ability to solve battery safety issues, and capabilities to fulfill the increasing demand for energy storage in electric vehicles and smart grid applications. Garnet-type solid electrolytes have attracted considerable interest as they meet all the properties of an ideal solid electrolyte for ASSLBs. The garnet-type Li7La3Zr2O12 (LLZO) has excellent environmental stability; experiments and computational analyses showed that this solid electrolyte has a high lithium (Li) ionic conductivity (10−4–10−3 S·cm−1), an electrochemical window as wide as 6 V, stability against Li metal anode, and compatibility with most of the cathode materials. In this review, we present the fundamentals of garnet-type solid electrolytes, preparation methods, air stability, some strategies for improving the conductivity based on experimental and computational results, interfacial issues, and finally applications and challenges for future developments of LLZO solid electrolytes for ASSLBs.

A muon facility—EMuS (Experimental Muon Source)—at China Spallation Neutron Source (CSNS) has been studied since 2007. CSNS, which is designed to deliver a proton beam power of 100 kW at Phase-I, and will serve multidisciplinary research based on neutron scattering techniques, has just completed construction, and is ready to open to general users from September 2018. As an additional platform to CSNS, EMuS aims to provide different muon beams for multiple applications, among which, magnetism study by μSR techniques is a core part. By using innovative designs, such as a long target in conical shape situating in superconducting capture solenoids and forward collection method, EMuS can provide very intense muon beams with a proton beam of 5 kW and 1.6 GeV, from surface muons, decay muons, and high momentum muons to slow muons. In this article, the design aspects of EMuS, including general design, target station, muon beamlines, and μSR spectrometer, as well as prospects for applications on magnetism studies, will be reviewed.

The quantum effect of light nuclei in materials is usually considered as lattice vibration and zeropoint motion (ZPM) from an ab initio perspective. Here we start from full-quantized particles and take the muon as an example, considering the two-body quantized system of the muon and the electrons within Two-Component Density Functional Theory, which can calculate the related twobody wave functions directly and automatically taking into account the quantum effect of the muon. This is an attempt to reveal the quantum effect of light nuclei in materials from a different respect.It is tested in some metallic systems (Fe-bcc, Co-fcc, Co-hcp) and some non-metallic systems(NaF, CaF2, diamond), we finally find this fundamental method agrees better with experiments and shows good potential for further such study.

No abstract