Thermal diffusion was used to dope Co atoms into ZnO single crystal. Particle-induced x-ray emission combined with channeling technique, x-ray diffraction, and ultraviolet-visible light absorption show that Co-diffused ZnO is pure single-phase alloy. The temperature variation of magnetization can be fitted by a linear combination of the Curie law and the Curie-Weiss law with negative Curie-Weiss temperature (−175K). In the high temperature region, the Co-doped ZnO layer is paramagnetic. In the low temperature region, antiferromagnetism and paramagnetism coexist. Evidence of ferromagnetic hysteresis behavior was not observed down to 5K.
A novel interfacial in situ modification for Li7(Al0.1)La3Zr2O12 is designed and prepared by using a spark plasma sintering method. The modified interface with most grain boundary area exhibits excellent interfacial electrochemical properties. The X‐ray diffraction (XRD) and scanning electron microscope (SEM) data indicate that the interfacial modified specimen (spark plasma sintering method, 1000 °C, 5 min) with 38.2(6) nm grain diameter and 32,134 cm2/g grain boundary specific surface area has the highest ionic conductivity (8.84×10−4 S/cm−1). The lithium‐ion transmission mechanism in grain‐internal and grain boundaries is revealed by ab initio theory, using Materials Studio software. Furthermore, the first‐principles calculation data indicate that the migration barrier of Li+ at the Li7(Al0.1)La3Zr2O12 solid electrolyte grain boundary is 0.21 eV, which is only 2/3 of that in the grain internal (0.33 eV). As a result, SPS interfacial in situ processing technology can increase the grain boundary area, thereby reducing the ion transport barrier and the interfacial impedance of the material.
Uniform silicon films about 500 nm thick for lithium‐ion batteries on copper foil current collectors were prepared using a magnetron sputtering method. We discuss the surface morphology and crystal structure of the silicon films, emphasizing how the current collector affects the performance of the silicon film anode. XRD and Raman analysis demonstrate that both films are amorphous. However, the silicon film deposited onto the matte copper foil shows better cycle behavior, it can be discharged at 0.5 C with 84.1 % capacity retention about 1470 mAhg−1 after 100 cycles.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.