Phase Structure Research Articles

Pressure-induced structural phase transitions and metallization in cuprous oxide under different hydrostatic environments up to 25.3 GPa

High-pressure vibrational and electrical transport behaviors of cuprous oxide were systematically investigated in a diamond anvil cell through in-situ Raman spectroscopy and electrical conductivity measurements under different hydrostatic environments up to 25.3 GPa. Upon compression, Cu2O undergoes a series of structural transformations from Cu2O–I to Cu2O–Ia to Cu2O–Ib to Cu2O–II to Cu2O–III at the respective pressures of 1.7(2), 10.3(2), 12.9(3) and 21.0(2) GPa under non-hydrostatic condition. Meanwhile, the metallization of Cu2O at 19.5(3) GPa is well characterized by the variable-temperature electrical conductivity experiments. Under hydrostatic condition, the pressure delay of 0.6 GPa–1.6 GPa is detected in the phase transitions from Cu2O–Ia to Cu2O–Ib to Cu2O–II to Cu2O–III phases. Upon decompression, one huge discrepancy is observed in the Raman spectra and electrical conductivity before and after the metallization, which indicates the irreversibility of phase transitions under different hydrostatic environments.

Structure and microwave dielectric characteristics of (Ba,Sr,Ca)HfO3 ceramics

In the present work, the structure and microwave dielectric properties of (Ba,Sr,Ca)HfO3 ceramics were systematically investigated to understand the general mechanism of tuning the temperature coefficient of resonant frequency, τf in perovskite ceramics. Ba1–xSrxHfO3 and Sr1–yCayHfO3 could form continuous solid solutions while the solid solubility of Ca in Ba1–yCayHfO3 was about 20% (in mole). τf changed nonlinearly with increasing tolerance factor as the result of competition between the increase in the restoring force on the ions and the increase in polarizability. Under the guidance of three microscopic mechanisms affecting τf, a preliminary attempt was made to explore the suitable parameters to predict the variation trend of τf. Normalized ionic radii and the τf values of the end members were selected as independent variables, and τf was calculated by using multiple linear regression method. For Ba1–xSrxHfO3 and Sr1–yCayHfO3 with orthorhombic structures, the root mean square error between the calculated and measured τf was only 6.8×10–6 °C–1. The good agreement between the calculated τf values and the measured ones in Ba1–x–ySrxCayHfO3 ceramics confirmed its validity where three elements jointly occupy A-site, but it only works when there is no structural phase transition. Progresses in this research field would not only deepen our understanding of mechanism of regulating properties in multi-ion solid solutions, but also boost the developments of closely related fields such as machine learning-assisted design and high-entropy ceramics. Finally, a good combination of microwave dielectric properties was achieved in Sr0.15Ca0.85Hf0.96Ti0.040O3: εr = 27.8, Qf = 36,470 GHz, τf = +5×10–6 °C–1.

Anatase to Rutile Transition in TiO2 Thin Films: Role of Tantalum and Oxygen

The present study discusses the optimal solubility limit of tantalum in anatase TiO2 thin films (dopant solubility limit) and its effect on crystal structure transformation to the rutile phase. The study also focuses on the role of lattice oxygen in this structural phase transition. The detailed chemical composition, constitution, and phase of these sputter-deposited thin films are correlated with their electrical and optical properties to understand the disparity between total impurity concentration in these films and actual impurity substitution into the host lattice sites (dopant content). Reduced oxygen vacancies from the oxygen lattice sites and/or Ta substitution in Ti lattice sites are found to hinder the anatase to rutile phase transformation in TiO2 thin films. Our experimental data indicates the solubility limit of Ta being < 5 at. % in TiO2. Similar behavior is seen when Ta is replaced with Nb in TiO2 thin films. Moreover, an increased oxygen and/or impurity concentration is found to lead to impurity-rich-oxides in these films, degrading the electrical conductivity.

Evolution of magnetization of Bi1-ySmyFe1-xTixO3 ceramics at the morphotropic phase boundary attested by multistep magnetization measurements, time aging and electric field

Bi1-ySmyFe1-xTixO3 ceramics with compositions at the rhombohedral- orthorhombic morphotropic phase boundary (y = 0.1, 0.12, 0 ≤ x ≤ 0.1) were prepared by solid state reaction method. Analysis of the crystal structure of the compounds based on the results of laboratory and synchrotron X-ray diffraction measurements as well as Raman spectroscopy experiments revealed a coexistence of the rhombohedral phase (SG R3c) and the anti-polar orthorhombic phase (SG Pbam) in the compounds Bi0.88Sm0.12Fe1-xTixO3 with 0 ≤ x ≤ 0.1; the compounds Bi0.9Sm0.10Fe1-xTixO3 are characterized by the mixed structural state for the concentration range 0 ≤ x ≤ 0.06 and by the single phase rhombohedral state within 0.06 < x ≤ 0.1. Room temperature magnetization measurements demonstrate a gradual increase of remanent magnetization with Ti content in the compounds of both systems up to the maximal value of MR ∼ 0.28 emu/g for compounds with x = 0.06 which is followed by a decrease in magnetization with further titanium doping. Temperature decrease leads to a reduction of remanent magnetization which is mainly caused by a partial recovery of spatially modulated spin structure occurred in the compounds of both systems. Time aging of the compounds for about ∼ 1 year leads to a drastic increase of MR, which is caused by a change in the structural phase ratio, homogeneity of the structural state and a contribution of unbounded spins demonstrated by low field measurements. Subjecting of the annealed compounds to external electric field of E ∼ 40kV/cm leads to a decrease of magnetization associated with backward structural transformations and redistribution of the local structural defects in the compounds.

Optical Study on Temperature-Dependent Absorption Edge of γ-InSe-Layered Semiconductor

We have studied the variations in the temperature-dependent absorption edge of a bulk InSe-layered semiconductor using photoconductivity (PC) measurements. From both the X-ray diffraction (XRD) and Raman experimental results, the structural phase of the as-prepared InSe sample was confirmed to be γ-polytype. Upon heating from 15 K to 300 K, the absorption edge of PC spectra was found to shift significantly toward lower energy, and the absorption edge as a function of temperature was further analyzed by the Varshni’s relationship and Bose–Einstein empirical equation. The Urbach energy as a function of temperature was obtained by fitting the absorption tail below the absorption coefficient of the PC spectrum, and the effective phonon energy can be derived from the temperature-dependent steepness parameter associated with Urbach energy. Our study indicates that the broadening of the absorption edge in the as-synthesized bulk γ-InSe is caused by a combination of electron/exciton–phonon interactions and thermal/structural disorder.

Investigations on the Structure, Mechanical Property, Wear and Oxidation Resistances of TiAlSiN Coatings by Tailoring Al/(Al + Ti) Ratios

Previous studies have broadly dealt with TiAlSiN coatings that exhibit promising characteristics as surface protective layers for antiwear and antioxidation applications. In this regard, revealing the correlations among coating composition, structure, and properties is vitally important for developing advanced TiAlSiN coatings. The present work addresses the issue by studying the structure and properties of TiAlSiN coatings by tailoring Al/(Al + Ti) ratios. To this end, TiAlSiN coatings are produced by arc deposition with the Al/(Al + Ti) ratios of 0.31, 0.42, 0.51, and 0.62, respectively. The results show that, when the Al/(Al + Ti) ratio ranges from 0.31 to 0.51, the phase structure is mainly TiN phase, and the hardness, wear resistance and oxidation resistance of the films are increased with the rise in the Al/(Al + Ti) ratio. When the Al/(Al + Ti) ratio reaches 0.62, the oxidation resistance of the coating does not improve significantly, while the mechanical and wear properties of the coating are deceased due to the formation of w‐AlN phase. Therefore, the appropriate Al/(Al + Ti) ratio at 0.51 provides overall improvements including mechanical properties, and wear and oxidation resistances under operation conditions. These findings show that optimizing the Al/(Al + Ti) ratio is a promising way to develop TiAlSiN coatings with advanced structure and properties.

Second-Order Nonlinear Switching and Photoluminescence Properties of Cd-Based Hybrid Perovskite with High-Temperature Phase Transition.

Recently, organic-inorganic hybrid perovskites exhibiting facile structural phase transitions have accumulated significant attention due to their switchable second-order nonlinear optical (NLO) properties, which hold significant promise for next-generation intelligent optoelectronic devices. In this study, we present a novel one-dimensional hexagonal hybrid perovskite, (4-methoxypiperidinium)CdCl3, which undergoes a reversible high-temperature structural phase transition at 389 K. Notably, (4-methoxypiperidinium)CdCl3 demonstrates switchable second-order NLO and dielectric properties, accompanied by symmetry breaking from the centrosymmetric Pnma to noncentrosymmetric Pna21 space group. Variable-temperature structure analyses reveal that this transition is mainly driven by the order-disorder transformation of the 4-methoxypiperidinium cations. Furthermore, it also features a promising photoluminescence performance with blue-light emission and a long lifetime of 25.34 ns. It is anticipated that this study will expand the family of hybrid perovskites exhibiting high-temperature phase transitions and offer valuable guidance for the design of new NLO switching materials with superior optoelectronic properties.

Stability of phase composition and properties of Zn4+xSb3 medium-temperature thermoelectric material

The phase composition and thermoelectric properties of a β-Zn4Sb3 based material before and after thermocycling tests at 273–723 K have been studied. Specimens with stoichiometric Zn and Sb molar ratios and with additions of different excess Zn quantities have been synthesized by direct component smelting followed by spark plasma sintering. The phase composition and structure of the materials have been studied using X-ray diffraction and transmission electron microscopy. The thermal conductivity and specific heat of the materials have been measured with laser flash and differential scanning calorimetry techniques. The phase composition of the as-synthesized, as-sintered and as-thermocycled Zn4+xSb3 thermoelectric material has been found to vary depending on excess Zn content in the charge. Excess Zn has been shown to dissolve in the β-Zn4Sb3phase upon spark plasma sintering and thermocycling. β-Zn4+xSb3 solid solution depletion of interstitial zinc atoms or ZnSb phase precipitation upon thermocycling increase the thermal conductivity and reduce the thermoelectric efficiency of the material. The Zn4.1Sb3 composition has shown high thermoelectric efficiency, the 715 K ZT being ∼1.23 and 1.18 before and after thermocycling, respectively.

Synthesis, structural phase transition and weak itinerant magnetism in NixNbSe2

The article presents the synthesis, structural and magnetic properties of NixNbSe2 (x = 0, 0.05, 0.1, 0.15, 0.2, 0.25). The intercalation limit of Ni in NbSe2 is found to be 25 mol%, above which NiSe appears as a binary impurity phase. Single crystal X-ray diffraction studies show that all the compounds crystallize in the hexagonal P63/mmc space group. However, there is a distinct phase transition beyond x = 0.20 with Ni intercalation in NixNbSe2. The NixNbSe2 compounds crystallized in the parent 2H phase with x value between 0 ≤ x ≤ 0.2. Subsequently, the phase transforms into the 2H(I) phase with an order superstructure of 2 ao × 2 ao × 1 co for 0.20 ≤ x ≤ 0.25 in NixNbSe2. The superstructure formation is attributed to the occupation of Ni at the alternate octahedral voids present in the van der Waals gap of the NbSe2. The XPS results and theoretical analysis clearly show that the intercalation of Ni results in a more metallic character in NixNbSe2. Magnetic measurements on NixNbSe2 (x = 0.05, 0.1, 0.2, 0.25) shows very small magnetic moment at low temperature for all the compounds. Theoretical calculation on Ni0.25NbSe2 shows that the Ni-3d electrons are delocalized and are very weakly spin-polarized, which may be the reason for the experimentally observed weak magnetism in these compounds.

Structural evolution and mechanical response of multiple Al Σ5(210) grain boundaries with segregation of solute atoms: First-principles study

Grain boundary (GB) segregation of solute atoms is a key factor affecting the microstructure and macroscopic properties of materials. In this study, first-principles calculations were carried out to investigate the effect of solute atoms (Mg and Cu) segregation on the structural evolution and mechanical response of Al ground-state Σ5(210) GB (GB-Ⅰ) and metastable Σ5(210) GBs (GB-Ⅱ and GB-Ⅲ). The GB energy, segregation energy, and the theoretical tensile strength of the multiple Σ5(210) GBs were calculated. The results show that both Mg and Cu atoms tend to segregate in the boundary plane, thus reducing GB energy and improving GB stability. The segregation of Cu atoms reduced the GB energy more significantly than that of Mg atoms. The segregation of solute atoms can change the symmetric GB structure into an asymmetric one or induce GB phase transformation. The theoretical strength of GB-I is weaker than that of the metastable GB-II with higher GB energy, suggesting that grain boundaries with higher energy are not necessarily unstable. In addition, the effect of solute atom segregation on the GB strength depends not only on the type of element but also on the specific GB structure. The weakening effect of Mg segregation in GB-I and GB-II is due to the weak MgAl bond which enlarges the low charge density region of GB and increases the free volume of GB. The strengthening of GB-I and GB-II by Cu segregation mainly depends on the stronger AlCu bond than AlAl bond along the GB fracture path. The enhanced strength of GB-III with Mg and Cu segregation is attributed to the GB structural phase transformation caused by the segregation of solute atoms. The calculation results further elucidate the relationship between element segregation and grain boundary characteristics.

Influence of heat treatment on the microstructure evolution and corrosion performance of biodegradable Zn-Mg alloys

Zinc and zinc-based alloys have garnered increasing attention as biodegradable materials due to their excellent mechanical properties, lower degradation rates compared to magnesium, and favorable biocompatibility. This study investigates the impact of homogenization treatment on the microstructure and corrosion behavior of Zn-Mg alloys using scanning electron microscopy, X-ray diffraction, hardness testing, and accelerated corrosion immersion tests. The results reveal that homogenization treatment induces the fusion of eutectic cells within the alloys, causing significant morphological alternations in the eutectic structure and varying proportions of the Mg2Zn11 phase, These changes notably affect material properties. The raised content of Mg2Zn11 phase in the eutectic structure correlates with higher hardness but reduced corrosion resistance, whereas the reduced Mg2Zn11 phase content leads to enhanced corrosion resistance. Furthermore, in-situ corrosion observations demonstrate that corrosion initiates at the eutectic phase, with corrosion pits forming due to the ion release as corrosion progresses, leading to gradual enlargement of the corrosion pits. In summary, this study provides comprehensive insights into the microstructural changes in Zn-Mg alloys and their impact on corrosion resistance, offering valuable references for their engineering applications.

Enhanced thermophysical and mechanical properties of gadolinium zirconate ceramics via non-stoichiometric design

Rare-earth zirconate ceramics are potential materials for thermal barrier coatings due to their low thermal conductivity and excellent structural stability. However, the low thermal expansion coefficient and fracture toughness limit their application and further improvements are needed. In this work, non-stoichiometric gadolinium zirconate ceramics with fluorite phase structure were successfully prepared using solid-state reaction method. HRTEM, iDPC-STEM, and in-situ XRD were employed to investigate nanostructure, lattice defects, and phase stability. The non-stoichiometric ratio introduces more defects and forms special nanostructures, enhancing the thermophysical properties of gadolinium zirconate ceramics. The non-stoichiometric gadolinium zirconate ceramics have lower phonon thermal conductivity with higher hardness and fracture toughness compared to stoichiometric ratio ceramics. In addition, the non-stoichiometric gadolinium zirconate ceramics exhibit excellent structural stability in a wide temperature range. These performances provide further applications for non-stoichiometric gadolinium zirconate ceramics as thermal barrier coatings.

Probing intrinsic magnetic domain in bare CrI3 bulk with a magnetic force microscope

Two-dimensional magnetism in CrI3 links to its stacking structural order. In bulk CrI3, coexistence of monoclinic and rhombohedral phases has been observed across wide temperature range. Direct characterization of the magnetic textures on the exposed surface of bulk CrI3 has been challenging but meaningful. Here, we have employed a custom glovebox-assisted magnetic force microscope to observe the evolution of magnetic domains on the bare CrI3 surface under variable temperatures and magnetic fields for the first time. Below the Curie temperature, robust parallel stripe magnetic domains spontaneously emerge. The root mean square values of the localized weak pinning domain images at various temperatures indicate a critical transition behavior consistent with 3D Ising model with Tc ∼ 59 K. Images obtained by varying the magnetic field at low temperatures, showing magnetization saturation-reentry cycles, reveal larger hysteresis and stronger disorder compared to the VSM measurement, indicating local structural phase inhomogeneity. ​Two in-plane stripe magnetic domains oriented locally at an angle of 51-degrees compete under an out-of-plane magnetic field, presumably due to different sliding orientations induced by the magnetic field during the transition from a monoclinic to a rhombohedral phase. This study provides an experimental reference for future spin density wave manipulation in CrI3.

Incorporation of Pd Single-atom Sites in Perovskite with an Excellent Selectivity toward Photocatalytic Semihydrogenation of Alkynes.

Semihydrogenation is a crucial industrial process. Noble metals such as Pd have been extensively studied in semihydrogenation reactions, owing to their unique catalytic activity toward hydrogen activation. However, the overhydrogenation of alkenes to alkanes often happens due to the rather strong adsorption of alkenes on Pd active phases. Herein, we demonstrate that the incorporation of Pd active phases as single-atom sites in perovskite lattices such as SrTiO3 can greatly alternate the electronic structure and coordination environment of Pd active phases to facilitate the desorption of alkenes rather than further hydrogenation. Furthermore, the incorporated Pd sites can be well stabilized without sintering by a strong host-guest interaction with SrTiO3 during the activation of H species in hydrogenation reactions. As a result, the Pd incorporated SrTiO3 (Pd-SrTiO3) exhibits an excellent time-independent selectivity (> 99.9 %) and robust durability for the photocatalytic semihydrogenation of phenylacetylene to styrene. This strategy based on incorporation of active phases in perovskite lattices will have broad implications in the development of high-performance photocatalysts for selective hydrogenation reactions.

Structural phase transition and optical properties of zero-dimensional cobalt bromide hybrid material

Zero-Dimensional (0D) metal halide materials have recently emerged as a class of potential optoelectronic materials because of the structural diversity and superior photophysical properties. Here we report a 0D cobalt bromide hybrid material, [Br(CH2)3NH3]2CoBr4 (BPA-CoBr4, BPA=Br(CH2)3NH3, 3-Bromopropylamine), in which the isolated metal halide tetrahedron (CoBr42-) is completely separated each other and surrounded by the organic ligand Br(CH2)3NH3+. Differential scanning calorimetry (DSC) measurements exhibit BPA-CoBr4 undergoes a first-order structural phase transition, as clearly visible to a pair of weak peaks at 340 K (heating) and 317 K (cooling). Single crystal X-ray diffractions were carried out at 293 K and 360 K to explain the phase transformation mechanism, indicating it is an isostructural order–disorder type. The crystal structures which both crystalize in a monoclinic P21/c crystal symmetry and the most distinct difference between room-temperature and high-temperature structures is the order–disorder transition of the 3-Bromopropylamine, which is the driving force of the phase transition. The UV–vis absorption spectra reveal that BPA-CoBr4 has a steep absorption edge at 280 nm corresponding to photo energy of 4.4 eV. The density functional theory (DFT) calculations were performed to study the electronic structure with narrower indirect bandgap 3.9 eV which is lower than the experimental values. PDOS plots show that the electronic states of Co-d and Br-p orbitals are mainly contributed for the VBM and CBM of BPA-CoBr4.

Higher Order Topological Defects in a Moiré Lattice

AbstractTopological defects are ubiquitous, they manifest in a wide variety of systems such as liquid crystals, magnets or superconductors. The recent quest for non‐abelian anyons in condensed matter physics stimulates the interest for topological defects since they can be hosted in vortices in quantum magnets or topological superconductors. In addition to these vortex defects, this study proposes to investigate edge dislocations in 2D magnets as new building blocks for topological physics since they can be described as vortices in the structural phase field. It demonstrates the existence of higher order topological dislocations within the higher order moiré pattern of the van der Waals 2D magnet CrCl3 deposited on Au(111). Surprisingly, these higher order dislocations arise from ordinary simple edge dislocations in the atomic lattice of CrCl3. This study provide a theoretical framework explaining the higher order dislocations as vortices with a winding Chern number of 2. It is expected that these original defects can stabilize some anyons either in a 2D quantum magnet or within a 2D superconductor coupled to it.

Chemical pressure induced spin reorientation in the magnetic structure of Ca3Mn2−xSnxO7 ( x=0,0.03,0.05 )

The effect of partially substituting Tin (Sn) at the Manganese (Mn) site of Ca3Mn2O7 , viz. Ca3Mn2−xSnxO7 with x=0.03,0.05 , on its structural and magnetic properties have been investigated using synchrotron diffraction, neutron diffraction, and bulk magnetization measurements. It is observed that with a substitution of x=0.03 , the minor (≈8%) tetragonal ( I4/mmm ) structural phase that is present in the predominantly orthorhombic ( Cmc21 ) undoped Ca3Mn2O7 , completely disappears. The compounds order antiferromagnetically, the ordering temperature decreases with increasing Sn-content, indicating a weakening of the antiferromagnetic exchange interactions. Interestingly, in the ordered state, the spin magnetic moments which were aligned along the a-axis of the unit cell in the undoped compound, are observed to have reoriented with their major components lying in the b − c plane in the Sn-doped compounds. The above influence of Sn-doping is seen to be stemming from a significant modification of the octahedral rotation and tilt mode geometry in the unit cell, that is known to be responsible for driving ferroelectricity in these compounds.

Understanding the structural relation and electrochemical evolution between ZnGeP2 and ZnSiP2 twin phosphides for advanced Li-ion batteries

Ternary ZnGeP2 with large capacity and suitable plateau is considered to be alternative anode for LIBs, while it suffers heavy-use of Ge raw-material inducing high cost-price thus failure of commercialization. Herein, a unique atomic substitution strategy is proposed by using Si-atom to totally replace Ge site in ZnGeP2. Interestingly, novel ZnSiP2 as twin-analogue is achieved, keeping the great advantages of high ICE (90 %), low plateau (∼0.35 V) and comparable rate performance (4000 mA/g, 629 mAh/g) for LIBs. More specially, such ZnSiP2 twin even exhibits higher thermo-stability (1046 vs 891 °C), larger capacity (1554 vs 1387 mAh/g) and lower voltage-hysteresis (0.28 vs 0.44 V) than ZnGeP2, which are unexpected and attractive for battery-safety and energy improvement. The above unusual phenomena are investigated in-detail, and the results show that owing to the similar radius and electronegativity between Si&Ge, the ZnSiP2 enables the same structural phase with ZnGeP2 matrix thus keeping its electrochemical advantages. Meanwhile, the ZnSiP2 exhibits larger formation energy (−1.24 eV) toward better structural-stability, lighter Si-component to higher capacity, lower Si-lithiated potential oriented smaller voltage-hysteresis, thus showing high performances in LiCoO2//ZnSiP2 full-cell. The above atomic substitution strategy can be easily extended to other good performance yet high cost electrode materials toward application.

Optimizing the microstructure and enhancing the mechanical prsoperties of hypereutectic Al–Si alloys by Mg addition

The impact of Mg on the solidification structure of hypereutectic Al–Si alloys with different Si contents (15 wt% and 18 wt%) was investigated. 3%Mg was added to Al–15Si alloy to modify the phases in the solidification structure for the improvement of mechanical properties, and T6 heat treatment was used to optimize the microstructure and precipitate strengthening phase. The solidification structure was observed by OM and TEM respectively, and the precipitation behavior of each phase was detected through DSC. The results show that the addition of Mg decreased the undercooling of the alloy melt, thus suppressing the precipitation of primary Si phase. Nanoscale β” precipitates were precipitated in the matrix after T6 heat treatment. This resulted in an increase of 54% and 165% in the UTS and EL of the alloy, reaching 252 MP and 15.1%, respectively. Primary Si crystals were present in two forms in Al–18Si–8Mg alloy: spinel twin and non-twin, while Mg2Si always maintained the faceted crystals during the growing process, where only (100) and (111) crystal planes were observed. XRD, SEM and EBSD have been used to prove that Mg2Si crystals with different morphologies could become the heterogeneous nuclei of two types of primary Si crystals. The process of nucleation and growth of primary Si with Mg2Si as the heterogeneous nuclei was experimentally analyzed and theoretically predicted.

Effect of Citrate-Based Bath pH on Properties of Electrodeposited Cu–Zn Coating on an Aluminum Substrate

In this study, Cu–Zn alloys were deposited in citrate-based electrolytes on aluminum substrate by electrodeposition method. The effect of bath pH variation on the properties of the obtained Cu–Zn alloy coatings was investigated. The electrochemical behavior of the citrate-based baths and the crystalline structure, surface morphology and elemental content, electrical resistivity and thermal behavior of the alloy coatings were analyzed. According to the results of cyclic voltammetry (CV) analysis, increasing bath pH caused a negative shift in the cathodic deposition potential. In addition, the anodic dissolution peaks first shifted to the positive side with increasing pH and then shifted back to the negative direction. According to the results of XRD analysis, the phase structure of Cu–Zn alloys generally consists of α and β′ phases, but according to differential scanning calorimeter (DSC) analysis, it is possible that there is a γ phase in the structure in addition to these phases. In addition, pH increase (4.5 to 6.5) caused a relative increase in crystal grain size (~14 to ~ 25 nm). The Zn content of Cu–Zn coatings first increased (~pct 15 to ~ pct 55) with pH increase, then followed a horizontal trend (~pct 55 to ~ pct 59) with further pH increase and then exhibited a slight decreasing trend (~pct 59 to ~ pct 52). The pH increase significantly affected the surface morphology of the coatings and denser coatings were obtained with increasing pH. While the electrical resistivity of Cu–Zn coatings first increased (0.0408 to 0.0696 µΩcm for 297 K) with increasing pH, it tended to decrease (0.0696 to 0.0479 µΩcm for 297 K) again at higher pH values. In addition, the electrical resistivity of the coatings increased with increasing measurement temperature. According to DSC analysis of the coatings, endothermic peaks were obtained, possibly representing the transformation from γ to β′ phase.Graphical