Solid polymer electrolytes (SPEs) have attracted considerable attention due to the rapid development of the need for more safety and powerful lithium ion batteries. The prime requirements of solid polymer electrolytes are high ion conductivity, low glass transition temperature, excellent solubility to the conductive lithium salt, and good interface stability against Li anode, which makes PEO and its derivatives potential candidate polymer matrixes. This review mainly encompasses on the synthetic development of PEO-based SPEs (PSPEs), and the potential application of the resulting PSPEs for high performance, all-solid-state lithium ion batteries.

Stable water-suspendable Cu+-doped ZnS nanocrystals (NCs) have been synthesized with mercaptopropionic acid (MPA) as a capping molecule. The nanocrystals have been characterized using a combination of experimental techniques including UV-vis and photoluminescence (PL) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma (ICP), and extended X-ray absorption fine structure (EXAFS). The UV-vis electronic absorption spectrum shows an excitonic peak at 310 nm, characteristic of quantum-confined ZnS NCs. This excitonic peak does not change noticeably with Cu+ doping. XRD confirms the formation of ZnS nanocrystals, and the average size of the NCs has been determined to be around 6 nm by TEM. The incorporation of Cu+ into the ZnS is manifested as a substantial red-shift of the emission band in the PL spectra upon addition of Cu2+ that was reduced into Cu+ during the synthesis reaction. EXAFS data were obtained to confirm copper doping as well as determine the local structure about Cu+ and Zn2+ in the NCs. Fitting to the EXAFS data for Cu+ suggests that most Cu+ ions are located near the surface within the ZnS NCs and that a significant fraction may be in the form of CuS as found in bulk material. These combined optical and structural studies have provided important new insight into the relevant electronic energy levels and their correlation to the optical and structural properties of ZnS:Cu,Cl NCs. This has important implications in potential applications of this phosphor material for solid state lighting, imaging, and other photonic devices.

Uranium and plutonium's 5f electrons are tenuously poised between strongly bonding with ligand spd-states and residing close to the nucleus. The unusual properties of these elements and their compounds (e.g., the six different allotropes of elemental plutonium) are widely believed to depend on the related attributes of f-orbital occupancy and delocalization for which a quantitative measure is lacking. By employing resonant X-ray emission spectroscopy (RXES) and X-ray absorption near-edge structure (XANES) spectroscopy and making comparisons to specific heat measurements, we demonstrate the presence of multiconfigurational f-orbital states in the actinide elements U and Pu and in a wide range of uranium and plutonium intermetallic compounds. These results provide a robust experimental basis for a new framework toward understanding the strongly-correlated behavior of actinide materials.

A composite electrode composed of Fe3O4 microspheres encapsulated in hollow graphene shells exhibits high electrochemical performance when used as an anode in a lithium ion battery.

In operando Raman spectroscopy was used to monitor the origin of the pseudocapacitive behavior of Mn3O4 electrodes during charging/discharging processes.

Manganese oxides of different structures, especially α-MnO 2 , have been extensively studied as electrodes for pseudocapacitors. However, the poor stability associated with intercalation of proton has been the main obstacle to their commercial applications. To effectively mitigate this problem, it is necessary to fully understand the energy storage mechanism of the MnO 2 phases. In this study, δ phase MnO 2 has been synthesized through controllable electroplating on architectural Ga-doped ZnO (GZO) bones, demonstrating a high specific capacitance of 1,068 F g -1 and high stability (slight performance drop focus on the first 2,000 cycles and then remained relatively constant in the subsequent 13,000 cycles). The charge storage mechanism of the δ-MnO 2 coated GZO has been carefully investigated at this limiting reaction 2 condition. Results suggest that the amount of charge stored in the electrode material correlates well with the amount of Na + inserted into the electrode material from the electrolyte. It is also noted that no spectral features corresponding to H + insertion were detected during cycling when the sample was probed using in operando Raman spectroscopy. Therefore, for layered δ-MnO 2 , a charge storage mechanism of Na + intercalation/deintercalation dominated, accompanied by interlayer spacing expansion/contraction, is proposed. Moreover, theoretical calculations also confirmed that the insertion of Na + is more energetically favorable than H + at all sites of the interlayer in δ-MnO 2 , offering a rational explanation of the proposed mechanism and the observed excellent stability.

Co2P and CoxN nanoparticles embedded nitrogen-rich nanocarbons were fabricated, serving as high-performance bifunctional electrocatalysts for oxygen reduction and evolution.

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