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This paper aims to investigate the photocatalytic activity of zinc doped MAO-TiO₂ films under the optimum MAO treatment condition.

The coating was prepared by micro arc oxidation, and the influence of doping on the properties of the coating was also investigated.

The results show that the BET surface area is 78.25±0.03m²/g, total pore area is 76.32 ± 0.04m²/g, and the total pore volume is 0.2135 ± 0.0004cm³/g. The degradation ratio of the film electrode with Zn-doped in methyl orange solution is up to 94%. When the react circles is 10 times, the degradation ratio is up to more than 85% and remains steady. With the different reaction conditions, these kinetics of the reactions show some different formulas.

A kinetic equation for photocatalytic activity is established.

This study aims to investigate the potential of the decorated boron nitride nanocage (BNNc) with transition metals for capturing carbon monoxide (CO) as a toxic gas in the air.

BNNc was modeled in the presence of doping atoms of titanium (Ti), vanadium (V), chromium (Cr), cobalt (Co), copper (Cu) and zinc (Zn) which can increase the gas sensing ability of BNNc. In this research, the calculations have been accomplished by CAM–B3LYP–D3/EPR–3, LANL2DZ level of theory. The trapping of CO molecules by (Ti, V, Cr, Co, Cu, Zn)–BNNc has been successfully incorporated because of binding formation consisting of C → Ti, C → V, C → Cr, C → Co, C → Cu, C → Zn.

Nuclear quadrupole resonance data has indicated that Cu-doped or Co-doped on pristine BNNc has high fluctuations between Bader charge versus electric potential, which can be appropriate options with the highest tendency for electron accepting in the gas adsorption process. Furthermore, nuclear magnetic resonance spectroscopy has explored that the yield of electron accepting for doping atoms on the (Ti, V, Cr, Co, Cu, Zn)–BNNc in CO molecules adsorption can be ordered as follows: Cu > Co >> Cr > Zn ˜ V> Ti that exhibits the strength of the covalent bond between Ti, V, Cr, Co, Cu, Zn and CO. In fact, the adsorption of CO gas molecules can introduce spin polarization on the (Ti, V, Cr, Co, Cu, Zn)–BNNc which specifies that these surfaces may be used as magnetic-scavenging surface as a gas detector. Gibbs free energy based on IR spectroscopy for adsorption of CO molecules adsorption on the (Ti, V, Cr, Co, Cu, Zn)–BNNc have exhibited that for a given number of carbon donor sites in CO, the stabilities of complexes owing to doping atoms of Ti, V, Cr, Co, Cu, Zn can be considered as: CO →Cu–BNNc >> CO → Co–BNNc > CO → Cr–BNNc > CO → V–BNNc > CO → Zn–BNNc > CO → Ti–BNNc.

This study by using materials modeling approaches and decorating of nanomaterials with transition metals is supposed to introduce new efficient nanosensors in applications for selective sensing of carbon monoxide.

This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at different powers. Film structure has been analyzed by X-ray diffraction (XRD); the patterns showed that the films possesses a cubic structure with (111) preferred orientation. Photoluminance (PL) intensity of the films has been related to the crystallinity, which is varied with the power.

Scanning electron microscope (SEM) images have been used to discover the films’ morphology. The stoichiometry has been confirmed by energy dispersive X-ray spectroscopy (EDX) analysis. MicroRaman spectroscopy has been used to validate the film structure. Gas-sensing studies were carried out by means of a static gas chamber to sense acetone, ethanol, methanol, H₂O and NH₃ vapor in air ambient.

ZnS has a stoichiometric and cubic structure. The band gaps and photoluminance intensity of the films are correlated with the crystallinity, which is varied with the power. The EDX analysis approved the stoichiometry of the prepared films. Acetone, ethanol, humidity (H₂O), methanol and NH₃ vapor gases were used to justify the sensing properties at 25°C of the thickest ZnS film.

High-quality ZnS films have been obtained at different powers without annealing. Gases sensing properties at 25°C are justified for deposited ZnS films using acetone, ethanol, humidity (H₂O), methanol and NH₃ vapor gases. It reveals good response for NH₃ and humidity vapors at room temperature; the sensing functioning at this temperature was attractive in recent research.

The purpose of this paper is to review and examine three of the most common corrosion characterization techniques specifically on Sn-Zn solders. The discussion will highlight the configurations and recent developments on each of the compiled characterization techniques of potentiodynamic polarization, potentiostatic polarization and electrochemical impedance spectroscopy (EIS).

The approach will incorporate a literature review of previous works related to the experimental setups and common parameters.

The potentiostatic polarization, potentiodynamic polarization and EIS were found to provide crucial and vital information on the corrosion properties of Sn-Zn solders. Accordingly, this solder relies heavily on the amount of Zn available because of the inability to produce the intermetallic compound in between the elements. Further, the excellent mechanical properties and low melting temperature of the Sn-Zn solder is undeniable, however, the limitations regarding corrosion resistance present opportunities in furthering research in this field to identify improvements. This is to ensure that the corrosion performance can be aligned with the outstanding mechanical properties. The review also identified and summarized the advantages, recent trends and important findings in this field.

The unique challenges and future research directions regarding corrosion measurement in Sn-Zn solders were shown to highlight the rarely discussed risks and problems in the reliability of lead-free soldering. Many prior reviews have been undertaken of the Sn-Zn system, but limited studies have investigated the corrosive properties. Therefore, this review focuses on the corrosive characterizations of the Sn-Zn alloy system.

The purpose of this paper is to investigate the ability of transition metals (TMs) of iron-, nickel- and zinc-doped graphene nanosheet for adsorption of toxic gas of nitric oxide (NO). The results of this paper have provided a favorable understanding of the interaction between TM-doped graphene nanosheet and NO molecule.

A high performance of TM-doped graphene nanosheet as a gas sensor is demonstrated by modeling the material’s transport characteristics by means of the Langmuir adsorption and three-layered ONIOM/ density functional theory method. The Langmuir adsorption model has been done with a three-layered ONIOM using CAM-B3LYP functional and LANL2DZ and 6–311G (d, p) basis sets by Gaussian 16 revision C.01 program towards the formation of of NO→TM(Mn, Co, Cu)-doped on the Gr nanosheet.

The changes of charge density for Langmuir adsorption of NO on Mn-, Co- and Cu-doped graphene nanosheet orderly have been achieved as: ΔQ_Co-doped = +0.309 >> ΔQ_Mn-doped = −0.074 > ΔQ_Cu-doped = −0.051. Therefore, the number of changes of charge density have concluded a more remarkable charge transfer for Mn-doped graphene nanosheet. However, based on nuclear magnetic resonance spectroscopy, the sharp peaks around Cu doped on the surface of graphene nanosheet and C19 close to junction of N2 and Co17 have been observed. In addition, Cu-doped graphene sheet has a large effect on bond orbitals of C8–Cu 17, C15–Cu 17 and C16–Cu17 in the adsorption of NO on the Cu-doped/Gr which has shown the maximum occupancy. The amounts of ΔGads,NO→Mn−Co through IR computations based on polarizability have exhibited that ΔGads,NO→Mn−Co has indicated the most energy gap because of charge density transfer from the nitrogen atom in NO to Mn-doped graphene nanosheet, though ΔG(NO→Cu−C)0> ΔG(NO→Co−C)0>ΔG(NO→Mn−C)0.

This research aims to explore the adsorption of hazardous pollutant gas of “NO” by using carbon nanostructure doped by “TM” of iron, nickel and zinc to evaluate the effectiveness of adsorption parameters of various TM-doped graphene nanosheets.

Aqueous zinc-ion battery has broad application prospects in smart grid energy storage, power tools and other fields. Co₃O₄ is one of the ideal cathode materials for water zinc-ion batteries due to their high theoretical capacity, simple synthesis, low cost and environmental friendliness. Many studies were concentrated on the synthesis, design and doping of cathodes, but the effect of process parameters on morphology and performance was rarely reported.

Herein, Co₃O₄ cathode material based on carbon cloth (Co₃O₄/CC) was prepared by different temperatures hydrothermal synthesis method. The temperatures of hydrothermal reaction are 100°C, 120°C, 130°C and 140°C, respectively. The influence of temperatures on the microstructures of the cathodes and electrochemical performance of zinc ion batteries were investigated by X-ray diffraction analysis, scanning electron microscopy, cyclic voltammetry curve, electrochemical charging and discharging behavior and electrochemical impedance spectroscopy test.

The results show that the Co₃O₄/CC material synthesized at 120°C has good performance. Co₃O₄/CC nanowire has a uniform distribution, regular surface and small size on carbon cloth. The zinc-ion battery has excellent rate performance and low reaction resistance. In the voltage range of 0.01–2.2 V, when the current density is 1 A/g, the specific capacity of the battery is 108.2 mAh/g for the first discharge and the specific capacity of the battery is 142.6 mAh/g after 60 charge and discharge cycles.

The study aims to investigate the effect of process parameters on the performance of zinc-ion batteries systematically and optimized applicable reaction temperature.

The purpose of this paper is to study the effects of voltage on microstructure and properties of micro-arc oxidation (MAO) ceramic coatings formed on AZ31B magnesium alloy under the constant current–constant voltage operation mode.

The wear and corrosion resistance of MAO coating on AZ31B magnesium alloy was studied by MAO in silicate electrolyte under constant current and constant voltage.

When the voltage is 360 V, the wear and corrosion resistance of AZ31B magnesium alloy is the best.

The wear and corrosion resistance of MAO coating on AZ31B magnesium alloy was studied by friction wear and electrochemical workstation.

This paper aims to analyze the effect of cerium addition on the microstructure and the mechanical properties of Tin-Silver-Copper (SAC) alloy. The mechanical properties and refined microstructure of a solder joint are vital for the reliability and performance of electronics. SAC305 alloys are potential choices to use as lead-free solders because of their good properties as compared to the conventional Tin-Lead solder alloys. However, the presence of bulk intermetallic compounds (IMCs) in the microstructure of SAC305 alloys affects their overall performance. Therefore, addition of cerium restrains the growth of IMCs and refines the microstructure, hence improving the mechanical performance.

SAC305 alloy is doped with various composition of xCerium (x = 0.15, 0.35, 0.55, 0.75, 0.95) % by weight. Pure elements in powdered form were melted in the presence of argon with periodic stirring to ensure a uniform melted alloy. The molten alloy is then poured into a pre-heated die to obtain a tensile specimen. The yield strength and universal tensile strength were determined using a fixed strain rate of 10 mm per minute or 0.1667 mm s^(−1). The IMCs are identified using X-ray diffraction, whereas the elemental phase composition and microstructure evolution are, respectively, examined by using electron dispersive spectroscopy and scanning electron microscopy.

Improvement in the microstructure and mechanical properties is observed with 0.15% of cerium additions. The tensile test also showed that SAC305-0.15% cerium exhibits more stress-bearing capacity than other compositions. The 0.75% cerium doped alloy indicated some improvement because of a decrease in fracture dislocation regions, but microstructure refinement and the arrangement of IMCs are not those of 0.15% Ce. Different phases of Cu_6 Sn_5, Ag_3 Sn and CeSn_3 and ß-Sn are identified. Therefore, the addition of cerium in lower concentrations and presence of Ce-Sn IMCs improved the grain boundary structure and resulted refinement in the microstructure of the alloy, as well as an enhancement in the mechanical properties.

Characterization of microstructure and evaluation of mechanical properties are carried out to investigate the different composition of SAC305-xCerium alloys. Finally, an optimized cerium composition is selected for solder joint in electronics.

This paper aims to review recent advances and applications of abrasive processes for microelectronics fabrications.

More than 80 patents and journal and conference articles published recently are reviewed. The topics covered are chemical mechanical polishing (CMP) for semiconductor devices, key/additional process conditions for CMP, and polishing and grinding for microelectronics fabrications and fan-out wafer level packages (FOWLPs).

Many reviewed articles reported advanced CMP for semiconductor device fabrications and innovative research studies on CMP slurry and abrasives. The surface finish, sub-surface damage and the strength of wafers are important issues. The defects on wafer surfaces induced by grinding/polishing would affect the stability of diced ultra-thin chips. Fracture strengths of wafers are dependent on the damage structure induced during dicing or grinding. Different thinning processes can reduce or enhance the fracture strength of wafers. In the FOWLP technology, grinding or CMP is conducted at several key steps. Challenges come from back-grinding and the wafer warpage. As the Si chips of the over-molded FOWLPs are very thin, wafer grinding becomes critical. The strength of the FOWLPs is significantly affected by grinding.

This paper attempts to provide an introduction to recent developments and the trends in abrasive processes for microelectronics manufacturing. With the references provided, readers may explore more deeply by reading the original articles. Original suggestions for future research work are also provided.

The research on lead-free solder alloys has increased in past decades due to awareness of the environmental impact of lead contents in soldering alloys. This has led to the introduction and development of different grades of lead-free solder alloys in the global market. Tin-silver-copper is a lead-free alloy which has been acknowledged by different consortia as a good alternative to conventional tin-lead alloy. The purpose of this paper is to provide comprehensive knowledge about the tin-silver-copper series.

The approach of this study reviews the microstructure and some other properties of tin-silver-copper series after the addition of indium, titanium, iron, zinc, zirconium, bismuth, nickel, antimony, gallium, aluminium, cerium, lanthanum, yttrium, erbium, praseodymium, neodymium, ytterbium, nanoparticles of nickel, cobalt, silicon carbide, aluminium oxide, zinc oxide, titanium dioxide, cerium oxide, zirconium oxide and titanium diboride, as well as carbon nanotubes, nickel-coated carbon nanotubes, single-walled carbon nanotubes and graphene-nano-sheets.

The current paper presents a comprehensive review of the tin-silver-copper solder series with possible solutions for improving their microstructure, melting point, mechanical properties and wettability through the addition of different elements/nanoparticles and other materials.

This paper summarises the useful findings of the tin-silver-copper series comprehensively. This information will assist in future work for the design and development of novel lead-free solder alloys.