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In spite of the excellent electrochemical performance in lithium-ion batteries (LIBs), transition-metal compounds usually show inferior capacity and cyclability in sodium-ion batteries (SIBs), implying different reaction schemes between these two types of systems. Herein, coupling operando magnetometry with electrochemical measurement, we peformed a comprehensive investigation on the intrinsic relationship between the ion-embedding mechanisms and the electrochemical properties of the typical FeS2/Na (Li) cells. Operando magnetometry together with ex-situ transmission electron microscopy (TEM) measurement reveal that only part of FeS2 is involved in the conversion reaction process, while the unreactive parts form "inactive cores" that lead to the low capacity. Through quantification with Langevin fitting, we further show that the size of the iron grains produced by the conversion reaction are much smaller in SIBs than that in LIBs, which may lead to more serious pulverization, thereby resulting in worse cycle performance. The underlying reason for the above two above phenomena in SIBs is the sluggish kinetics caused by the larger Na-ion radius. Our work paves a new way for the investigation of novel SIB materials with high capacity and long durability.

The (002) texture, compactness, and smoothness Ti2AlN thin films render them promising for many potential applications, especially in the surface modification of wear-resistant components. In this study, Ti2AlN thin films were fabricated by the vacuum annealing of Ti/AlN multilayers deposited by high power pulsed magnetron sputtering (HPPMS). The influence of the multilayer modulation ratio and modulation period of Ti/AlN on the microstructure and properties of the Ti2AlN thin film were explored. The results indicate that a Ti/AlN modulation ratio close to 6:4 and period less than 30 nm are appropriate for yielding high-quality crystallized Ti2AlN thin films. The microstructure of the Ti2AlN thin film is (002) textured, nanocrystalline, smooth, and compact, which benefits from the HPPMS technique. The Ti2AlN thin film adheres well to the substrate and has a hardness of 32.5 ± 2.1 GPa and has a friction coefficient of 0.15 while tested with a Si3N4 friction pair.

Ti-Mn-N films were deposited on CoCrMo alloys and Si substrate by reactive magnetron sputtering. The effects of Mn content on the structure, surface composition and surface energy of Ti-Mn-N film were investigated by XRD, SEM, XPS, and contact angle measurements. Primary mouse osteoblasts were cultured on the Ti-Mn-N films for 1 and 3 d to evaluate cell adhesion and cell viability. RAW264.7 macrophages were cultured on the Ti-Mn–N films for 24 h to evaluate the cell activation and inflammatory cytokine release. The results showed that after culturing for 3 days, there were a greater number of osteoblasts on the 2.2%Mn-TiN and 4.4%Mn-TiN films as compared to the other films. When the Mn content was higher than 4.4 at.%, the osteoblasts viability on Ti-Mn-N films was reduced. In addition, the results of the released inflammatory factors showed that Ti-Mn-N films induced a lower inflammatory response than that induced by CoCrMo alloy, while demonstrating the same excellent biocompatibility as that of TiN film. Hence, Ti-Mn–N films with 2.2 at.% and 4.4 at.% Mn have potential application on the surface modification of dental implant.

The influence on the tribological properties in a modified metal‐on‐polymer (CoCrMo/UHMWPE) articulation should be tested with DLC coated or N + ion implanted into artificial hip joint heads. For this a diamond like carbon (DLC) film was deposited on a CoCrMo artificial hip joint head by filtered cathodic vacuum arc technique (FCVA) with a thickness of approximately 600 nm. Alternatively nitrogen ions were implanted into the CoCrMo artificial hip joint head by plasma immersion ion implantation (PIII) technology. Before wear tests, the surface morphology and topography of unmodified, DLC coated and N + implanted CoCrMo heads were investigated by optical microscopy (OM) and stylus profilometry. Then a MTS hip joint simulator was used to characterize the tribological properties of the artificial hip joint implants. The wear loss of UHMWPE cup and wear morphology of both the CoCrMo head and UHMWPE cup were investigated after hip joint simulator wear tests. The results showed that the DLC film deposited on the CoCrMo joint head by FCVA method had excellent tribological properties and didn't fail during two million wear cycles while the N + implanted layer formed on the CoCrMo head was damaged during the wear test. Compared with sliding against unmodified CoCrMo head, the UHMWPE cup had a higher wear rate when sliding against DLC coated or N + implanted CoCrMo head. In our opinion, only applying the surface modification (DLC film or N + implantation) on the CoCrMo head could not improve the wear resistance of metal‐on‐polymer (CoCrMo/UHMWPE) articulation for artificial hip joint implant.

CuO/tetrapod-like ZnO whisker (T-ZnOw) nanocomposites were successfully synthesized using a simple photo-deposition method. Some nanocomposites exhibit remarkably improved photocatalytic property, while the extents of the improvements vary with different Cu/Zn molar ratios and polyethylene glycol (PEG) concentrations. Moreover, it is found that excessively high Cu/Zn molar ratio or PEG concentration would reduce the photocatalytic property of the nanocomposites. A direct relationship between the morphology and the photocatalytic property of CuO/T-ZnOw was established and then analyzed by discussing the photocatalytic mechanism of the CuO/T-ZnOw nanocomposites.

In this work, ultrahigh molecular weight polyethylene (UHMWPE) was modified with oxygen plasma generated by microwave electron cyclotron resonance (ECR). Surface microstructure and properties of UHMWPE were studied by means of water contact angle measurement, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy, scratch test and wear test. The results showed that O 2 plasma treatment could effectively improve the wettability, anti-scratch and tribological properties of UHMWPE. Many oxygen-based functional groups generated on the surface of the O 2 plasma modified UHMWPE, which resulted in the improvement of wettability. The plasma treatment process increased the crosslinking of UHMWPE molecular chains, which further enhanced the action force between the molecular chains and finally increased the surface hardness, anti-scratch capacity and tribological properties of UHMWPE.

The paper presents the investigation of the effect of the process parameters on the structure of hydrogenated amorphous carbon (a-C:H) films deposited on Si(100) substrate by electron cyclotron resonance microwave plasma chemical vapor deposition method (ECR-PCVD). The investigation is based on an orthogonal experimental design and analysis method. Both the carbon sp3/sp2 bonding ratio and hydrogen content are evaluated from the visible Raman spectra deconvolution. The statistical results indicate that the sp3/sp2 bonding ratio is mainly affected by microwave power, and it decreases as the microwave power increases. The hydrogen content in a-C:H films is mainly affected by the substrate bias voltage, and it decreases with increasing the bias voltage. The effect of other parameters on the structure of a-C:H films is relatively not significant, but is also discussed in the paper.

In this work, argon (Ar) plasma generated by microwave electron cyclotron resonance (MWECR) has been used to modify the UHMWPE in order to increase the wear resistance. The results showed that the wettability, anti-scratch and wear resistance of UHMWPE treated by the Ar plasma had been improved, comparing with native UHMWPE. The FTIR and XPS spectra indicated the improvement of wettability should come from the oxygen based functional groups generated on the surface of UHMWPE. The improvement of anti-scratch and wear resistance may come from the enhancement of crosslinking of UHMWPE by Ar plasma treatment.

In prosthetic hip replacements, ultrahigh molecular weight polyethylene (UHMWPE) wear debris is identified as the main factor limiting the lifetime of the artificial joints. Especially UHMWPE debris from the joint can induce tissue reactions and bone resorption that may lead to the joint loosening. The diamond like carbon (DLC) film has attracted a great deal of interest in recent years mainly because of its excellent tribological property, biocompatibility and chemically inert property. In order to improve the wear-resistance of UHMWPE, a-C:H films were deposited on UHMWPE substrate by electron cyclotron resonance microwave plasma chemical vapor deposition (ECR-PECVD) technology. During deposition, the working gases were argon and acetylene, the microwave power was set to 800 W, the biased pulsed voltage was set to −200 V (frequency 15 kHz, duty ratio 20%), the pressure in vacuum chamber was set to 0.5 Pa, and the process time was 60 min. The films were analysed by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, nano-indentation, anti-scratch and wear test. The results showed that a typical amorphous hydrogenated carbon (a-C:H) film was successfully deposited on UHMWPE with thickness up to 2 μm. The nano-hardness of the UHMWPE coated with a-C:H films, measured at an applied load of 200 μN, was increased from 10 MPa (untreated UHMWPE) to 139 MPa. The wear test was carried out using a ball (O 6 mm, SiC) on disk tribometer with an applied load of 1 N for 10000 cycles, and the results showed a reduction of worn cross-sectional area from 193 μm 2 of untreated UHMWPE to 26 μm 2 of DLC coated sample. In addition the influence of argon/acetylene gas flow ratio on the growth of a-C:H films was studied.