The intrinsic zinc oxide (ZnO) thin films with controllable crystallographic orientation have been synthesized on Si(100) substrates using plasma-enhanced chemical vapor deposition (PECVD) system without any buffer layer. Based on X-ray diffraction (XRD) results, the evolution of crystallographic orientation of ZnO thin films from polar c-plane (0002), polar c-plane and nonpolar m-plane (101̅0) coexist to nonpolar m-plane and a-plane (112̅0) coexist was achieved by a simple factor of controlling synthesized temperature. The plane-view morphological images exhibited that the surface texture and grain shape of ZnO thin films could have evolved from hexagonal to stripelike grains when the ZnO crystallographic orientation changed from perpendicular to parallel to the substrate. The characterization analysis indicated that the zinc precursor [diethylzinc (DEZn), Zn­(C2H5)2] played a key role on the crystallographic orientation evolution of ZnO thin films during the early stage of the growth process because DEZn not only can serve as Zn precursor but also can be employed as passivating agent to influence the crystal growth under different synthesized temperatures. Room-temperature Hall effect measurement showed that intrinsic ZnO thin film with stripelike grains possessed the lowest value of resistivity ∼7.11 × 102 Ω cm, which had an estimated carrier concentration and mobility of about 5.73 × 1014 cm–3 and 15.34 cm2/V s, respectively. The water contact angle (CA) measurement was also provided to determine the surface wettability and surface free energy of ZnO thin films, indicating that CA could be adjusted via different crystallographic orientation of ZnO thin film.

In the archetypal lithium-rich cathode compound Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 , a major part of the capacity is contributed from the anionic (O 2−/− ) reversible redox couple and is accompanied by the transition metal ions migration with a detrimental voltage fade. A better understanding of these mutual interactions demands for a new model that helps to unfold the occurrences of voltage fade in lithium-rich system. Here we present an alternative approach, a cationic reaction dominated lithium-rich material Li 1.083 Ni 0.333 Co 0.083 Mn 0.5 O 2 , with reduced lithium content to modify the initial band structure, hence~80% and~20% of capacity are contributed by cationic and anionic redox couples, individually. A 400 cycle test with 85% capacity retention depicts the capacity loss mainly arises from the metal ions dissolution. The voltage fade usually from Mn 4+ /Mn 3+ and/or O n− /O 2− reduction at around 2.5/3.0 V seen in the typical lithium-rich materials is completely eliminated in the cationic dominated cathode material.

The energetic particles bombardment can produce large internal stress in the zinc oxide (ZnO) thin film, and it can be used to intentionally modify the surface characteristics of ZnO films. In this article, we observed that the internal stress increased from −1.62 GPa to −0.33 GPa, and the naturally wettability of the textured ZnO nanostructured films changed from hydrophobicity to hydrophilicity. According to analysis of surface chemical states, the naturally controllable wetting behavior can be attributed to hydrocarbon adsorbates on the nanostructured film surface, which is caused by tunable internal stress. On the other hand, the interfacial water molecules near the surface of ZnO nanostructured films have been identified as hydrophobic hydrogen structure by Fourier transform infrared/attenuated total reflection. Moreover, a remarkable near-band-edge emission peak shifting also can be observed in PL spectra due to the transition of internal stress state. Furthermore, our present ZnO nanostructured films also exhibited excellent transparency over 80% with a wise surface wetting switched from hydrophobic to hydrophilic states after exposing in ultraviolet (UV) surroundings. Our work demonstrated that the internal stress of the thin film not only induced natural wettability transition of ZnO nanostructured films, but also in turn affected the surface properties such as surface chemisorption.

When B and V are added to CoFe material, the mechanical strength and spin tunneling polarization of a CoFe alloy can be improved and enhanced by the high tunneling magnetoresistance (TMR) ratio. Based on these reasons, it is worthwhile investigating Co40Fe40V10B10 films. In this work, X-ray diffraction (XRD) showed that Co40Fe40V10B10 thin films have some distinct phases including CoFe (110), CoFe (200), FeB (130), and V (110) diffracted peaks with the strongest diffracted peak for 30 nm. The lowest low-frequency alternate-current magnetic susceptibility (χac) was detected at 30 nm because the large grain distribution inducing that high coercivity (Hc) enhances the spin coupling strength and low χac. The external field (Hext) had difficulty rotating in the spin state, hence, the spin sensitivity was reduced and the χac value decreased due to increased surface roughness. The 20 mm thickness had the highest χac 1.96 × 10−2 value at 50 Hz of an optimal resonance frequency (fres). The surface energy increased from 34.2 mJ/mm2 to 51.5 mJ/mm2 for Co40Fe40V10B10 films. High surface energy had corresponding strong adhesive performance. According to the magnetic and surface energy results, the optimal thickness is 20 nm due as it had the highest χac and strong adhesion.

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