This study systematically investigated the effects of NbC, TaC, and (Ta,Nb)C additives on the microstructure, mechanical properties, and tribological properties of WC-based composites. The specimens with different additive contents were prepared via ball milling, pressing, and sintering, and were subsequently characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), hardness testing, friction and wear experiments. The results demonstrated that all additives refined WC grains, with NbC exhibiting the most pronounced refinement (a 31.3 % reduction in grain size at 0.8 wt%). In terms of mechanical properties, TaC and (Ta,Nb)C enhanced hardness but significantly reduced fracture toughness, whereas NbC improved hardness with a slower decline in toughness at 0.8 wt%. Wear tests revealed that the wear rate decreased from 1.05 x 10-5 to 8.96 x 10-6 mm3/(N & sdot;m) as the NbC content increased from 0 to 0.8 wt%. The composite (Ta,Nb)C additive exhibited weaker synergistic effects compared to the individual additives. The mechanisms for improving wear resistance involved grain refinement and hardness enhancement, providing theoretical guidance for the design of cemented carbides under extreme conditions.

To enhance the adsorption capacity and recoverablity of MXenes, the Ti3C2Tx were hydroxyl (OH) functionalized by a faicle alkalization treatment and the nanocomposite aerogel composed of Ti3C2(OH)0.08 and sodium alginate (SA) were subsequently fabricated. The alkalized Ti3C2Tx exhibited a maximum adsorption capacity (MAC) of 798 mg g-1 for U(VI), marking a 116 % increase over the untreated Ti3C2Tx. The adsorption experiment results were consistent with the Pseudo-second-order kinetics and the Langmuir isotherm model, confirming it is a chemisorption and monolayer adsorption. Aside from electrostatic adsorption (EA), the reduction adsorption (RA) was also found to happen during the adsorption process via a X-ray photoelectron spectroscopy (XPS) analysis, in which the U(VI) is reduced to U(IV) and the Ti(II) is oxidized to Ti(IV). The calculated adsorption energies and electron localization function (ELF) of U(VI) on the functional groups (F, O, OH) of Ti3C2Tx indicate that the OH functional group is most favorable to adsorb U(VI), which theoretically reveals the adsorption mechanism of EA&RA. Additionally, the Ti3C2(OH)0.08@SA aerogels demonstrate an efficient U(VI) adsorption even at an ultra-low concentration of 3.3 mu g/L U(VI) under simulated seawater environment. The advantages of excellent adsorption, easy recovery and good reusability of the MXene-based aerogels make them very beneficial for the future practical applications as U(VI) adsorbent.

Background: To tackle metal corrosion in harsh environments, this study introduces an eco-friendly and highperformance corrosion inhibitor based on nitrogen and phosphorus co-doped carbon dots (N,P-CDs). Methods: N,P-CDs were hydrothermally synthesized from L-histidine and phosphoric acid. FTIR, XPS, and TEM confirmed successful N and P incorporation. Their corrosion protection performance was evaluated electrochemically in 3.5 wt.% NaCl solution. Significant findings: The optimal phosphorus doping ratio of 10 % achieved a maximum inhibition efficiency of 96.57 % for copper at a concentration of 200 mg/L. The adsorption process was found to be spontaneous and to follow the Langmuir adsorption isotherm. Surface analysis, combined with XPS, indicated the formation of a dense protective film composed of copper oxides, chlorides, and coordination bonds involving heteroatoms from the inhibitor. Furthermore, molecular dynamics (MD) and quantum chemical (QC) simulations provided molecular-level insights, demonstrating that the N,P-CDs possessed a narrow energy gap (Delta E = 0.51 eV) and a high adsorption energy (-235.9 kJ/mol). These properties facilitated strong chemisorption onto the copper surface, elucidating the fundamental mechanism behind the effective corrosion protection.

The morphology, microstructure and U(VI) adsorption properties of a new M3X2Tx-type bimetallic Ti2VC2Tx MXene synthesized via a facile etching method were investigated. It is found that Ti2VC2Tx can adsorb U(VI) fast and efficiently, with a maximum adsorption capacity(MAC) of 619 mg/g being able to get at pH 6 within 20 min and excellent ion interference resistance under the simulated seawater environment. This adsorption capacity is exceeding most previously reported MXene- based adsorbents. The U(VI) adsorption on Ti2VC2Tx is a chemical, monolayer and endothermic sorption process, and can be attributed to the synergistic effect of electrostatic interaction between the negatively charged Ti2VC2Tx surface and the positive uranyl (UO22 +) and reduction reaction of U from U(VI) to U(IV). XPS analysis reveal that both Ti and V element provide electrons and participate in the U(VI) reduction reaction, with V enhancing the redox activity and electron donation capacity, which accounts for the better adsorption performance of the bimetallic Ti2VC2Tx than the mono-metallic Ti3C2Tx MXene. These findings provide a guide for further improving the U(VI) adsorption performance of MXene materials though simply optimizing the metal elemental species and ratios in MXenes.

NiFe-layered double hydroxide (NiFe-LDH) and La-, Mo- or W-doped NiFe-LDH microparticles (NiFeX-LDH, X = La, Mo, W) were synthesized via the co-precipitation method. Their adsorption characteristics were evaluated by the removal of methyl orange (MO) and hexavalent chromium (Cr6+). The effects of the metal ion doping type, doping concentration (0–3at%), pH and temperature on the MO adsorption properties were systematically studied. The results show that W-doped NiFe-LDH exhibits superior MO removal capacity compared to undoped or La- or Mo-doped NiFe-LDH at the same 1at% doping level, which is attributed to the increased layer charge density and strong affinity for the π-electron systems of MO molecules. The NiFeW-LDH-1at% sample demonstrated the best MO adsorption performance within the W-doping range of 0–3at%, achieving a superior adsorption capability of 666.67 mg/g with a significantly shorter equilibrium time (10–120 min) compared to the similar LDH. NiFeW-LDH-1at% showed promising reusability, with its adsorption efficiency remaining 78.3% of its initial level after five adsorption–desorption cycles. The MO uptake onto NiFeX-LDH was attributed to the combined effect of anion exchange and the attraction of layer charge. In addition, the adsorption of NiFeW-LDH-1at% matched well with the Langmuir isotherm model and pseudo-second-order kinetic model, indicating a monolayer and chemical adsorption. Furthermore, NiFeW-LDH-1at% effectively adsorbed of Cr2O72− in the aqueous solution, revealing that W doping significantly enhances Cr(VI) removal performance. The maximum theoretical adsorption capacity onto NiFeW-LDH-1at% reached 63.25 mg/g, which was notably higher than that of the pristine NiFe-LDH adsorbent (53.56 mg/g). Overall, the W-doped NiFe-LDH material, as a low-cost and highly efficient adsorbent, shows great potential for wastewater treatment application.

With the increasingly serious industrial pollution, the effective removal of heavy metal ions and organic pollutants from wastewater has become a key issue of environmental protection. In this paper, a new MXene material, TiVCTx, was prepared by in situ etching, and its adsorption capacity of heavy metal anion Cr(VI) and methylene blue (MB) dye cation was studied. The effect of adsorption time, pH values, temperatures, initial concentrations of adsorbent and adsorbate, interfering ions on the Cr(VI) and MB adsorption of TiVCTx was systematically investigated. It is found that TiVCTx has excellent Cr(VI) and MB adsorption property, the adsorption capacity can be as high as 600 mg/g and 1430 mg/g, respectively. The adsorption experiments revealed that the adsorption process of Cr(VI) conformed to the Langmuir isotherm model and the Pseudosecond-order kinetic model, which indicated that the Cr(VI) adsorption was a heat-absorbing monolayer chemisorption. In contrast, the adsorption process of MB is in accordance with the Freundlich isotherm model and the Pseudo-second-order kinetic model, suggesting that the MB adsorption was an exothermic multilayer chemisorption. The results of X-ray electron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis further confirmed that the reductive adsorption and electrostatic adsorption can account for the outstanding Cr(VI) and MB adsorption capacity of TiVCTx, respectively.

As the typical representative of amorphous oxide semiconductors (AOS), quaternary indium gallium zinc oxide (IGZO) has been applied as the active layer of thin-film transistors (TFTs), but their mobility is still low (usually ~10 cm2/Vs). IGTO is reported to have larger mobility owing to the addition of Tin (Sn) in IZO. So, whether Sn doping can increase the optoelectronic properties of IGZO is a new topic worth studying. In this study, four series of quinary InGaZnSnO (IGZTO) oxide thin films were deposited on glass substrates using a high-purity IGZTO (In:Ga:Zn:Sn:O = 1:0.5:1.5:0.25:x, atomic ratio) ceramic target by RF magnetron sputtering. The effects of fabrication parameters (sputtering power, argon gas flow, and target-to-substrate distance) and film thickness on the microstructure, optical, and electrical properties of IGZTO thin films were investigated. The results show that all IGZTO thin films deposited at room temperature (RT) are amorphous and have a smooth and uniform surface with a low roughness (RMS of 0.441 nm, RA of 0.332 nm). They exhibit good average visible light transmittance (89.02~90.69%) and an optical bandgap of 3.47~3.56 eV. When the sputtering power is 90 W, the argon gas flow rate is 50 sccm, and the target-to-substrate distance is 60 mm, the IGZTO films demonstrate optimal electrical properties: carrier concentration (3.66 × 1019 cm−3), Hall mobility (29.91 cm2/Vs), and resistivity (0.54 × 10−2 Ω·cm). These results provide a valuable reference for the property modulation of IGZTO films and the potential application in optoelectronic devices such as TFTs.

In this study, novel quinary InGaZnSnO indium gallium zinc tin oxide (IGZTO) thin films deposited on glass substrates using a high-purity IGZTO (atomic ratio In:Ga:Zn:Sn:O = 1:0.5:1.5:0.25:x) ceramic target via RF magnetron sputtering were annealed in air at room temperature to 450 degrees C. The effects of annealing temperature on the microstructure, electrical and optical properties of the thin films were systematically investigated. Both the as-deposited and the annealed IGZTO films exhibit amorphous structures. The film annealed at 150 degrees C demonstrated the best electrical performance, with a carrier concentration of 3.06 x 1019 cm-3, a mobility of 35.68 cm2 V-1 s-1 and resistivity of 5.70 x 10-3 Omega cm, while the one annealed at 350 degrees C had a carrier concentration of 3.58 x 1017 cm-3 and the smoothest surface, with the lowest root mean square (RMS) and average roughness (Ra) of 0.384 nm and 0.278 nm, respectively. As the annealing temperature increased from 150 degrees C to 450 degrees C, the optical energy gap (Eg) changed from 3.52 to 3.56 eV, and the Urbach energy (EU) increased from 170 to 274 meV, indicating the increased disorder and more defects generated after annealing. Oxygen vacancies are found to be the main origin of the conductivity of IGZTO films, and their minimum concentration was found in the film annealed at 350 degrees C. Thin-film transistors (TFTs) with 350 degrees C-annealed IGZTO thin film as the active layer exhibit a favorable field-effect mobility of 20.17 cm2 V-1 s-1, which is higher than that of most of the reported indium gallium zinc oxide (IGZO) TFTs. Our films are grown by single-target sputtering and their optoelectronic properties are easily regulated by the annealing temperature, so this work demonstrates a facile and convenient method for obtaining IGZTO films with appropriate electrical properties and high-performance IGZTO TFTs.

In this study, a novel quinary transparent conductive oxide (TCO) IGZTO thin films were fabricated using magnetron sputtering. The effects of sputtering power, argon gas flow, and target‐to‐substrate distance (ToSD) on the electrical properties of IGZTO thin films were systematically analyzed and compared. The results provide valuable insights for enhancing the electrical performance of IGZTO TFTs. It was observed that with increasing sputtering power, argon gas flow, and ToSD, the Hall mobility of the IGZTO films exhibited a trend of first increasing and then decreasing. At a sputtering power of 90 W, the IGZTO film possesses the highest Hall mobility of 26.83 cm 2 /V·s, whereas at 100 W, the highest carrier concentration of 20.53 × 10¹⁸ cm⁻³ is achieved. The Hall mobility of IGZTO films also showed a trend of first increasing and then decreasing with increasing argon gas flow, with optimal performance observed at 50 sccm, where the mobility reached 29.91 cm 2 /V·s. Additionally, the Hall mobility of the IGZTO films showed a similar trend with varying ToSD, with the best performance obtained at a ToSD of 60 mm. The study of IGZTO thin film properties under different process conditions is beneficial for the mass production and large‐scale application of IGZTO TFTs in the display industry.

MXenes are widely recognized as excellent dye adsorption materials. However, their propensity to oxidize will greatly reduce their stability and performance. In the present work, a simple antioxidation treatment was applied to TiVCTx using three acid antioxidants (oxalic acid (OA), sodium citrate (SC), and tartaric acid (TA)) and their effects on the stability and methylene blue adsorption performance were investigated. The stability of TiVCTx stored in an aqueous solution within 14 days was assessed using XRD and XPS. The antioxidant-treated TiVCTx showed a significant improvement in both long-term stability and MB adsorption properties, with TA-TiVCTx demonstrating the best performance. The MB adsorption of the as-prepared TiVCTx was physical and multilayer, but it became a multilayer process where physical and chemical adsorptions coexist after antioxidation treatment. The maximum adsorption capacity of TA-TiVCTx reached 8061.03 mg g-1 and remained at 3887.28 mg g-1 after 14 days of storage, far exceeding the performance of other reported adsorbents. It is found that the enhanced stability is attributed to the dense protective layer formed by the chelation between the antioxidant and TiVCTx, and the improved MB adsorption performance is ascribed to the synergistic effect of electrostatic adsorption between TiVCTx and MB and the Bloch reaction between the antioxidants and the MB molecules. The differences in the enhancement effects of the various antioxidants are related to the number of carboxyl and hydroxyl groups in the antioxidant molecules. This work provides useful reference and guidance for obtaining MXenes with better stability and adsorption performance.

The application of two-dimensional (2D) materials in the construction of van der Waals heterostructures (vdWHs) has proven to be an effective approach for generating superior optoelectronic performance. In this study, SnTe/InBr vdWHs are constructed from SnTe and InBr monolayers, and a detailed investigation is conducted on three configurations: SnTe/InBr-AA, SnTe/InBr-AB, and SnTe/InBr-AC. The influence of interlayer distance and biaxial strain on the electronic and optical properties of the 2D SnTe/InBr vdWHs is systematically investigated using density functional theory (DFT). It is found that all three configurations are type I heterojunctions. Notably, the type I heterojunction in the AC configuration can be transformed into a type II heterojunction by adjusting the interlayer distance. This transformation is expected to enhance charge separation efficiency and transport processes. Furthermore, the photovoltaic conversion efficiency (PCE) of the type II heterostructures can reach up to 17.06 %. Additionally, all three configurations exhibit exceptionally high light absorption coefficients, approximately 105cm-1. Moreover, these properties can be effectively modulated by introducing strain, where compressive stress induces a redshift and tensile stress induces a blueshift. This demonstrates that SnTe/InBr vdWHs have the potential to be ideal materials for designing 2D photodetectors and solar cells in the future.

The electrodes of thin film transistors (TFTs) have evolved from conventional single Cu layers to multi-layered structures formed by Cu and other metals or alloys. Different etching rates of various metals and galvanic corrosion between distinct metals may cause etching defects such as rough or uneven cross-sectional surfaces of stacked electrodes. Therefore, the etching of stacked electrodes faces new challenges. CD Bias and profile angle (PA) are two main performance indicators for the wet etching of TFT electrodes. Adjusting CD Bias and PAs quantitatively and evaluating their stability accurately is crucial to ensure the performance and yield of TFTs. In this work, the bilayer MoNb/Cu-stacked electrodes with different MoNb thicknesses and the MoNb/Cu/MTD triple-layered electrodes were prepared, and the influence of MoNb thickness and stacked structure on the CD Bias and PAs was investigated. It is found that in the H2O2-based etchant, the order of corrosion potential is EMTD < EMoNb < ECu; both MoNb/Cu and Cu/MTD will form a primary cell with MoNb or MTD as the anodes. The CD Bias and PAs of the MoNb/Cu bilayer structure also increase with MoNb thickness, but those of the MoNb/Cu/MTD triple-layered structure decrease with the introduction of the top MTD film. Finally, regression equations between CD Bias or PA and etching parameters were established based on the results of uniform experiments, and the 95% confidence intervals for CD Bias and PA were proposed after the Monte Carlo simulation. These obtained results provide a basis for quantitative adjustment of CD Bias and PA and precise control of etching stability.

MXenes are a group of novel two-dimensional (2D) materials with merits such as large specific surface area, abundant surface-functional groups, high chemical activity, excellent mechanical properties, high hydrophilicity, and good compatibility with various polymers. In recent years, many novel high-performance organic anticorrosion coatings using MXenes as nanofillers have been reported and have attracted widespread attention. As the first successfully prepared MXene material, Ti3C2Tx is the most extensively studied and typical member of the MXene family. Therefore, it is taken as the representative of its family, and the status of Ti3C2Tx MXene/epoxy resin (EP) and MXene/waterborne polyurethane (WPU) polymer anticorrosive composite coatings is reviewed. Firstly, the structure, characteristics, and main synthesis methods of MXenes are briefly introduced. Then, the latest progress of four surface-modification strategies to improve the dispersion, compatibility, stability, and anti-aggregation properties of MXenes, namely functionalization grafting, orientation regulation, heterostructure nanocomposite design, and stabilization and greening treatment, are analyzed and summarized. Finally, the current challenges and future opportunities regarding MXene-based corrosion-resistant organic composite coatings are discussed prospectively.

Spherical and flaky Ti3C2Tx were prepared successfully by adjusting the concentration of Ti3C2Tx solution in a freeze-drying method. The flaky Ti3C2Tx sample has a very high adsorption capacity and fast adsorption rate for Cr(vi).

Magnesium alloys, which are the lightest metal construction materials used in industry, play a vital role in future development. Magnesium alloys exhibit outstanding qualities such as low density, efficient electromagnetic shielding, and dimensional stability, making them highly valuable across a wide range of applications in automotive, medical, and electronic communication sectors, among others. However, Mg alloys are highly active and readily corrode in aqueous solutions or humid atmospheres. These alloys have limited applications because of their poor corrosion resistance. Composite coatings can improve the defects of a single coating to achieve better substrate protection. To improve the corrosion resistance of magnesium alloys, a micro -arc oxidation (MAO) / self -assembly (SAM) / nickel composite coating was fabricated on the surface of a magnesium alloy (AZ91D), via MAO, self -assembly by ethyl acetate (C4H8O2), and chemical plating with nickel. SEM and EDS were used to characterize the surface morphology and corrosion product content of the corrosion -processed samples. XRD and XPS tests were employed to analyze the changes in the surface material of the sample during corrosion. AFM was used to characterize the surface roughness of the sample during corrosion. Polarization curve and electrochemical impedance spectroscopy was used to assess the corrosion resistance of samples at various corrosion durations. The corrosion behavior of the composite coating in 3.5 wt.% NaCl environment was studied by morphological structure analysis, electrochemical tests, and corrosion product analysis, and the corrosion process model of the composite coating was established. The results show that the presence of Cl- accelerates the onset of corrosion. Polarization curves and impedance tests showed that the corrosion resistance of the MAO / SAM / Ni composite coating was significantly improved compared with that of the magnesium alloy matrix. The corrosion current density of the composite coating decreased by three orders of magnitude compared with that of the magnesium alloy. After 120 h of corrosion, the corrosion current density of the composite coating was still one order of magnitude lower than that of the magnesium alloy substrate, and the electrochemical impedance reached 1.16x10(4) Omega center dot cm(2). The results indicate that the composite coating significantly improved the corrosion resistance of the Mg alloy. The Mg alloy matrix corrodes within 24 h and generates corrosion products, including MgO and MgCl2, in an environment of 3.5 wt.% NaCl. The corrosion of the MAO / SAM / Ni composite coatings can be divided into three stages, namely early, middle, and late stages. The surface structure of the Ni layer remained dense when the composite coating was exposed to a salt -spray environment for 0-96 h. In the early stages of corrosion, the corrosion resistance of the coating improved, mainly owing to the formation of the corrosion product NiO, on the surface of the coating. As the corrosion time increased, trivalent NiOOH formed on the surface of the coating, and the coating gradually deteriorated. When the composite coating was exposed to a corrosive environment for 120 h, the Ni layer started deteriorating, and the corrosive ions penetrated and formed channels. Subsequently, the protection capabilities of the SAM and MAO layers diminished. After 144 h, the corrosive ions directly penetrated the composite coating, rendering the substrate coating ineffective. Once the outer layer of the electroless nickel plating was compromised, corrosion ions easily penetrated the composite coating, forming MgCl2 corrosion products. The results provide an experimental basis and theoretical foundation for the development, preparation, and application of such coatings.

The Cu undercut is a recently discovered new defect generated in the wet stripping process of MoNb/Cu gate stacked electrodes for thin-film transistors (TFTs). The formation mechanism and preventive strategy of this defect were identified and investigated in this paper. The impact of stripper concentration and stripping times on the morphology and the corrosion potential (Ecorr) of Cu and MoNb were studied. It is observed that the undercut is Cu tip-deficient, not the theoretical MoNb indentation, and the undercut becomes severer with the increase in stripping times. The in-depth mechanism analysis revealed that the abnormal Cu undercut was not ascribed to the galvanic corrosion between MoNb and Cu but to the local crevice corrosion caused by the corrosive medium intruding along the MoNb/Cu interface. Based on this newly found knowledge, three possible prevention schemes (MoNiTi (abbreviated as Mo technology development (MTD) layer/Cu), MoNb/Cu/MTD, and MoNb/Cu/MoNb) were proposed. The experimental validation shows that the Cu undercut can only be completely eliminated in the MoNb/Cu/MTD triple-stacked structure with the top MTD layer as a sacrificial anode. This work provides an effective and economical method to avoid the Cu undercut defect. The obtained results can help ensure TFT yield and improve the performance of TFT devices.

MXenes have demonstrated exceptional potential in the adsorption of uranium (U(VI)) from wastewater. However, significant challenges remain in the investigation of its adsorption capacity and mechanism. To enhance the adsorption capacity of Ti2CTx, this study conducted alkalization experiments on Ti2CTx and subsequently prepared Ti2C(OH)(0.13)@SA aerogel spheres by combining alkalized Ti2C(OH)(0.13) with sodium alginate (SA). The results indicated that alkalization effectively increased the proportion of OH functional groups. After alkalization treatment, Ti2C(OH)(0.13) exhibits a significantly enhanced adsorption capacity, reaching up to 951 mg g(- 1), which represents more than a twofold increase compared with untreated Ti2CTx. The adsorption follows pseudo-second-order kinetics and the Langmuir isotherm model, suggesting chemical and monolayer adsorption, respectively. Thermodynamic studies reveal an endothermic adsorption process. DFT calculations demonstrate that the OH functional group forms chemical bonds with U(VI), promoting reductive adsorption. Aside from electrostatic adsorption, XPS analysis confirms Ti(II) oxidation and U(VI) reduction. This study further investigates the adsorption capacity of Ti2C(OH)(0.13)@SA aerogel spheres in simulated seawater environments. It is found that even at an ultra-low concentration of U(VI) as low as 3.3 mu g/L, these aerogel spheres still exhibit significant adsorption performance, with an adsorption capacity reaching up to 3.21 mg g(-1), highlighting their substantial potential for applications.