Microstructure Of Deposits Research Articles

Examining the overlap between patterns of tau deposition and cortical neurite microstructure in preclinical Alzheimer’s disease

AbstractBackgroundIncreased Amyloid‐beta (Aβ) is associated with the neuropathological features of Alzheimer’s disease (AD), and it has been suggested to amplify tau spreading in the brain that leads to neurodegeneration. However, little is known about how the pattern of tau spreading overlaps with that of cortical microstructural neurodegeneration in the preclinical stages of the disease. Here, we utilized molecular imaging and neurite orientation dispersion and density imaging (NODDI) to identify the spreading pattern of tau pathology with the disease progression in cross‐sectional data and interaction with the degradation of cortical neurite microstructures.MethodsThe study consisted of normal controls (CN) and patients with mild cognitive impairments (MCI) from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) (Table 1). All participants had structural and multi‐shell diffusion magnetic resonance imaging (MRI), and positron emission tomography (PET) scans using 18F‐florbetapir (AV45) for and 18F‐flortaucipir (AV1451) for tau. The preprocessed PET images were used to generate the standardized uptake value ratio (SUVR) values in each hemisphere consisting of 180 cerebral cortical brain regions defined by the Glasser atlas. The preprocessed dMRI data were used to compute cortical NODDI coefficients (neurite density (intracellular volume fraction; ICVF), orientation dispersion index (ODI), and isotropic volume fraction (FISO)). The tau and NODDI microstructural values are then normalized compared to the Aβ− CN group by adjusting the values for age and sex. The tau spreading order was defined based on the frequencies of the normalized tau values that exceeded the given threshold and compared the patterns with the neurite microstructures.ResultsWe found a sharp increase of tau deposition in patients with Aβ+ MCI, and the medial temporal regions were identified as the earliest region to become tau positive and continue to spread to inferior temporal and inferior parietal regions. Most importantly, we found significant patterns of cortical ODI degradation with the tau spreading in the right entorhinal cortex (p = 0.004) and the right hippocampus (p = 0.02).ConclusionThe findings of this cross‐sectional study provide that regional cortical neurite imaging could provide higher sensitivity to changes in the pathological process of tau spreading in tau epicenters in AD.

Effects of deposition temperature on microstructures and ablative properties of SiC coatings prepared by CVD from methylsilane

Using the methylsilane (MS) as a gas precursor, SiC coatings were prepared on the surface of graphite by the chemical vapor deposition (CVD) method at different deposition temperatures. The effects of temperature on the deposition rate, microstructures and ablative properties of SiC coatings were investigated systematically. The results showed that the SiC deposition rate of SiC coating using MS at 1000 °C was 50–120 μm/h, which was much higher than that using methyltrichlorosilane (5–10 μm/h). The SiC coatings deposited at lower temperatures (900–1000 °C) exhibited smooth and spherical compact packing morphology, while the SiC coatings deposited at higher temperatures (1100–1200 °C) appeared to possess an irregular cauliflower morphology with an significantly increased size of SiC particles. Therefore, the SiC coating prepared at deposition temperature of 1000 °C had suitable density, roughness, and uniform size of coating microstructure. Meanwhile, the mass ablation rate and linear ablation rate of the obtained SiC coating were respectively 0.0096 mg/s and 0.3750 μm/s after plasma ablation at 2300 °C for 80 s, exhibiting excellent ablative resistance. This study provided a theoretical and technical foundation for the preparation of SiC coating using the MS as the gas precursor by the CVD method.

Heterogeneity of nanoparticle deposition micro-structure and modeling deposition layer thickness variation underneath periodically growing single boiling bubbles in nanofluids

Nanoparticle deposition in nanofluid boiling can significantly impact heat transfer efficiency. However, there is still much to be uncovered regarding the heterogeneity of micro-structures in nanoparticle deposition and how to quantitatively model variations in deposition layer thickness. To gain a deeper understanding, we conducted experiments where single boiling bubbles were grown from an artificial micro-cavity in SiO2 nanofluids with varying concentrations and durations under a constant heat flux. Our results reveal that the nanoparticle deposition region increases with concentration and boiling duration. Notably, while the deposition morphology is irregular near the bubble nucleation site, it becomes more uniform further away from the bubble nucleation site. We believe that the heterogeneity in the micro-structure of the deposition layer is due to differences in the evaporation time of the liquid microlayer at different positions, variations in its thickness beneath a single boiling bubble, and dependency of nanoparticles Brownian motion on temperature. Additionally, the thickness of the deposition layer decreases as the distance from the nucleation site increases. To accurately describe this variation in thickness, we have proposed a semi-empirical correlation based on the liquid microlayer evaporation theory and the conservation of mass of nanoparticles beneath a single boiling bubble. The thickness of the nanoparticle deposition layer is determined by the number of growing bubbles, liquid density, initial thickness of the liquid microlayer, local nanoparticle concentration, and local nanoparticle stacking density. This study provides valuable insights into optimizing micro-structures or thickness of the deposition layer, leading to improved nanofluid boiling heat transfer.

Effect of magnetic stirring on microstructure of Co deposit in electrowinning

The effect of magnetic stirring was investigated on the microstructure of Co deposits during electrowinning in a chloride solution. The microstructure of Co deposits obtained before and after using the magnetic stirring was systemically characterized. Cyclic voltammograms were carried out to investigate the electro-reduction of Co2+ ions. The nucleation and growth of Co deposits were discussed based on chronoamperometry. The evolution of H2 inevitably accompanied with the reduction of Co2+ ions in the electrowinning. It had a great influence on the structure of Co deposits. The introducition of magnetic stirring can reduce this negative influence effectively by promoting the detachment of H2 bubbles on the substrate. The magnetic stirring also changed the nucleation and growth of Co deposits. Finally, columnar Co crystals with intensively preferred orientation were prepared. The modification of microstructure by magnetic stirring is contributed to prepare high-quality Co electrodeposits.

Microstructure and crystallographic texture of direct energy deposition printed 316L stainless steel

The microstructural features and crystallographic texture of 316L stainless steel prepared by direct energy deposition (DED) are studied. The grain size, morphology, grain boundary, misorientation distribution along different direction and mechanical properties are characterized via detailed electron backscatter diffraction (EBSD) analysis and Vickers microhardness tester. The DED-built 316L stainless steel exhibits equiaxed cellular and elongated morphology. Only a few number of dislocations are accumulated and entangled near small grain boundary. The sample contains mainly large angle grain boundary. 316L stainless steel powder is melted to form a deep and shallow shape measured from the top view. The average grain size is 38.32 µm and 29.79 µm for the top and side view, respectively. Two strong textural components of {001}<100> cube texture and {110}<001> Goss texture are formed perpendicular and parallel to the scanning direction, respectively. The microhardness of DED-built 316L stainless steel achieves a higher average value of 261.74 HV.

Influence of process and heat input on the microstructure and mechanical properties in wire arc additive manufacturing of hot work tool steels

The present study demonstrates the suitability of wire arc additive manufacturing (AM) for hot work tool steel processing. Different arc welding techniques and energy inputs were applied and systematically compared to determine the deposition characteristics, microstructure and mechanical properties. All AM deposits show a sound visual appearance and full density without macroscopic imperfections, i.e. cracking. By adhering to a pre-defined interpass strategy, the cold metal transfer process can be used to achieve higher weld beads with lower dilution and faster build-up rates than the metal active gas process. The microstructure of the AM parts is comparable for all process configurations and consists of an α/α′-matrix with a finely dispersed vermicular and polygonal δ-ferrite network; no notable amount of retained austenite could be measured, but it could be observed by transmission electron microscopy embedded within the laths. Intensive precipitation of multiple molybdenum-based precipitates is observed along the interface matrix to δ-ferrite. In contrast, iron-based precipitates are predominantly found inside and at the boundaries of the laths of the matrix. Similarities are also evident in the mechanical properties, resulting in an average hardness of 380–390 HV1 and absorbed impact energy of 10–12 J at room temperature. High yield strength values of 1000–1100 MPa and ultimate tensile strength of 1200–1400 MPa were obtained. No significant differences in the measured mechanical properties could be noted regarding the specimen orientation, indicating the isotropy of the properties.

Operando Spatial Pressure Mapping Analysis for Prototype Lithium Metal Pouch Cells Under Practical Conditions.

Monitoring and diagnosing the battery status in real-time are of utmost importance for clarifying failure mechanism, improving battery performance, and ensuring safety, particularly under fast charging conditions. Recently, advanced operando techniques have been developed to observe changes in the microstructures of lithium deposits using laboratory-scale cell designs, focusing on understanding the nature of Li metal electrodes. However, the macroscopic spatial inhomogeneity of lithium electroplating/stripping in the prototype pressurized pouch cells has not been measured in real-time under practical conditions. Herein, a new noninvasive operando technique, spatial pressure mapping analysis, is introduced to macroscopically and quantitatively measure spatial pressure changes in a pressurized pouch cell during cycling. Moreover, dynamic spatial changes in the macroscopic morphology of the lithium metal electrode are theoretically visualized by combining operando pressure mapping data with mechanical analyses of cell components. Additionally, under fast charging conditions, the direct correlation between abrupt capacity fading and sudden increases in spatial pressure distribution inhomogeneity is demonstrated through comparative analysis of pouch cells under various external pressures, electrolyte species, and electrolyte weight to cell capacity (e/c) ratios. This operando technique provides insights for assessing the current battery status and understanding the complex origin of cell degradation behavior in pressurized pouch cells.

High performance tin-based Babbitt coatings deposited by high-pressure cold spraying

Tin-based Babbitt alloys are widely used as sliding bearing materials due to their excellent tribological properties such as good friction reduction, friction resistance and embeddedness. In this study, for the first time, tin-based Babbitt coatings (SnSb11Cu6) were deposited on 40Cr steel substrates by a high-pressure cold spraying system with dual downstream injection as a preliminary investigation of anti-friction coatings for sliding bearings. The effects of process parameters on deposition efficiency, microstructure, microhardness, bond strength and tribological properties of cold sprayed SnSb11Cu6 coatings were systematically investigated. Results showed that with the optimization of process parameters, deposition efficiency tends to increase first and then decrease, and the optimal deposition efficiency achieved is 53 %. The coating prepared at the gas pressure of 1.5 MPa and gas temperature of 450 °C has the highest density, and the best overall mechanical and tribological properties. XRD results showed that no phase change and oxidation occurred for coatings under all cold spraying conditions. The highest microhardness of cold sprayed SnSb11Cu6 coatings is 28.8 HV0.05, higher than that of as-cast alloy (~22.5 HV0.05). The bond strength between SnSb11Cu6 coatings and the steel was significantly increased by using bond coat and is highest as 21 ± 3 MPa. The lowest coefficient of friction and wear rate of the SnSb11Cu6 coatings is 0.23 and 7.99 × 10−5 mm3/N·m, respectively (pair: GCr15 ball, 3 N). The deposition mechanisms and wear mechanisms of cold sprayed SnSb11Cu6 coatings were also analyzed. With the optimization of process parameters, the particle physical state transits from semi-molten to fully-molten, and the bonding mechanism is mainly mechanical interlocking. The wear mechanisms of cold sprayed SnSb11Cu6 coatings are abrasive wear and adhesive wear, and abrasive wear dominates.

A novel directed energy deposition-arc method of deposition layer without focused thermal energy heating: droplet transfer, morphology and microstructure

Additive manufacturing (AM) of metal usually forms columnar grains along the building direction due to the focused thermal energy directly heating the deposition layer to easily obtain an obvious temperature gradient. The columnar grains are not conducive to AM-sample application, which results in the property anisotropy of the AM-sample. In this work, a novel directed energy deposition-arc (DED-Arc) method for depositing layers without direct heating by focused thermal energy is proposed. The arc burns between the tungsten electrode and a water-cooled electrode, were only used to melt the wire during DED-Arc process. Using stainless steel wire as a model alloy, by studying droplet transfer, morphology of the deposition layer and microstructure evolution, the feasibility of the method was fully verified. Two kinds of droplet transfer modes were observed, and the difference between them was whether the droplet contacted the molten pool before falling off. The focused thermal energy is only used to melt the wire, and the droplet transfer cycle is mainly affected by gravity, greatly decreasing the heat accumulation compared with existing methods. The heat-affected zone (HAZ) was obviously inhibited. The grain morphology of the deposition layer mainly consists of equiaxed crystals (∼300 μm) without an obvious preferred orientation. The deposition layer without direct heating by focused thermal energy could reduce the heat accumulation, resulting in a decrease in the temperature gradient and the morphology of equiaxed grains. The microstructure of a cylindrical sample was produced and has the same characteristics as with the deposition layer. The average microhardness of 172.63 HV, 167.95 HV and 169.26 HV are obtained in the top, middle and bottom regions, respectively. In addition, the tensile strengths are 500 MPa and 490 MPa, respectively.

Microstructural Study of Cold-Sprayed CoCrFeNiMn High Entropy Alloy

The rapid development of cold spraying technology for additive manufacturing of engineering components has made it a viable option for developing thick deposits from high-entropy alloys (HEAs). The microstructure of cold-sprayed CoCrFeNiMn deposit was investigated in this study using electron backscattered diffraction, scanning electron microscopy, and finite element analysis (FEA). The limited studies on the impact deformation behavior of the HEA during cold spraying, limiting our understanding of impact phenomena, and interactions between the HEA particles under ultra-high strain rate deformation motivated this study. From the microstructural characterization, heterogeneous microstructure appears to be formed in the cold-sprayed HEA deposit, comprising of equiaxed ultrafine grains at the particle–particle interfacial regions and coarse grains at the particle interiors. The FEA reveals large strain (> 250%) and temperature (> 90% of the alloy solidus temperature), mainly at the splat’s interfaces. Adiabatic shear instability and rotational dynamic recrystallization resulting from heat accumulation and high strain are believed to be responsible for these observations during the ultra-high strain rate deformation of the HEA. The large deformation and grain refinement experienced by the HEA resulted in greater deposit hardness when compared with the sprayed powder, with the nanohardness increasing from 1.16 GPa in the powder to 5.14 GPa in the deposit. This study explores and provides an understanding of the deformation behavior of the HEA and the resulting microstructure during cold spraying.

Synthesis, microstructure and electrochemical properties of Ni-P-based alloy coatings for hydrogen evolution reaction in alkaline media

Alkaline water electrolysis driven by renewable energy is a promising technology for green hydrogen generation. The cathode half-cell reaction i.e., the hydrogen evolution reaction (HER) in alkaline water electrolysis suffers from slow kinetics. Ni-P-based alloys have shown to be an efficient and cost-effective electrocatalyst to accelerate the HER rate. In this study, three Ni-P alloy coatings are prepared via electrodeposition by varying the deposition currents viz. 10 mA cm-2 direct, 10 mAcm-2 and 100 mAcm-2 pulsed currents. The XRD patterns of all the Ni-P coatings exhibited the formation of crystalline deposits and confirmed the alloying of P in Ni. The SEM images suggested that the microstructures of the Ni-P alloy deposits are highly dependent on the magnitude and waveform of the applied current employed during preparation of the alloy coatings. The composition of the alloy surface is Ni-rich in all three cases but exhibited local variations as evaluated by EDX. The surface distributions of Ni and P in the pulsed deposited samples are more uniform and homogeneous. The cyclic voltammetry patterns of the Ni-P coatings in KOH media exhibit characteristic peaks due to Ni/Ni3+ redox phenomenon. The Ni2+/Ni3+ oxidation peak area is lowest for the direct deposited sample and highest for the pulsed deposited one (100 mAcm-2). The Ni-P alloy electrocatalyst deposited under pulsed mode at 100 mAcm-2 exhibits a current density of −10 mAcm-2 at 0.09 V overpotential and is most active among all samples. The remarkable electrocatalytic activity of this sample is attributed to its smaller crystallite size, better morphological characteristics and lesser resistances to charge transfer and porosity.

Additive manufacturing of duplex stainless steels: assessment of deposition processes, microstructure, and properties

Additive manufacturing of duplex stainless steels: assessment of deposition processes, microstructure, and properties

Effect of interlayer coating La2O3 particles on arc behavior and microstructure of wire arc additive manufacturing Al-Si alloy deposition

In this paper, three kinds of ER4043 aluminum alloy depositions with the interlayer coating La2O3 particles were successfully fabricated by cold metal transfer (CMT) wire arc additive manufacturing (WAAM) technology, and the evolution of various La2O3 particles size on arc behavior, forming defects, microstructure and mechanical properties was described. The results indicated that arc length and horizontal diameter of the CMT-WAAM specimens were directly related to the size of coating La2O3 particles. When the interlayer was coated ordinary and micron-sized La2O3 particles, the violent arc fluctuations and welding spatter were generated and deteriorated forming quality. When the interlayer was coated nano-sized La2O3 particles, the proper arc deflection could improve the fluidity of the molten pool and promote the stomas escape to obtain excellent forming quality. The tensile strength in both horizontal and vertical directions increased to 209.17 MPa and 165.34 MPa, which were 22.55 % and 15.82 % higher than that of the additive specimen without coated powder, respectively. A majority of La2O3 particles were existed in grain boundaries in a form of like-eutectic. Additionally, some of dissociated La2O3 particles became heterogeneous nucleation sites and were included in the Al matrix. This process of interlayer coating nano-sized La2O3 provided more nucleation masses and further refined microstructure of the WAAM specimens during the solidification. The results from this study provided an essential reference to introduce rare earth oxides into deposited interlayer and improve the mechanical properties of CMT-WAAM depositions.

Systematic Approach to Optimize Technological and Economical Aspects of Atmospheric Plasma Sprayed Thermal Barrier Coatings

Plasma‐sprayed yttria‐stabilized zirconia coatings have been used in gas turbines for decades. They are applied for thermal insulation to increase operating temperature and hence efficiency and component's lifetime. To keep manufacturing costs low, especially deposition efficiency is important. However, increasing it is also related to a reduction in porosity, affecting the insulating properties of the layer. To find an optimal combination of efficiency and technological performance, a systematic study of the most affecting parameters of the atmospheric plasma spraying process is conducted, using response surface methodology. In detail, the influence of current, spraying distance, and hydrogen gas flow is investigated with respect to the deposition efficiency, porosity, microstructure, and mechanical properties of the coatings. Characterization is carried out by scanning electron microscopy, microindentation tests, and three‐point bending tests. The models generated based on these measured properties allow predictions of the system responses for any parameter variation in the investigated design space. In addition, a numerical model is developed for targeted optimization of the coating properties. This can be used to produce optimized coatings for load‐flexible gas turbines with high deposition efficiency, high porosity, and at the same time advantageous mechanical properties.

An induction heat treatment method for improving the mechanical properties and electrical conductivity of cold spray additive manufactured copper deposit

The metallic deposits produced by cold spray additive manufacturing (CSAM) often fail to meet the structural requirements, necessitating post-treatment. This study introduces induction heat (IH) to heat-treat the Cu deposit for the first time, and its influence on deposit microstructure and mechanical properties was analyzed. Microstructure analysis shows that IH treatment reduces dislocations and prevents pore formation, but increases grain size. Electrical conductivity significantly increases from 15 MS/m in the CSAM deposit to 31 MS/m after IH treatment, indicating improved bonding between particles. IH treatment can vastly enhance the mechanical properties of the CSAM deposit, increasing its tensile strength from 58 MPa and elongation at break from 1.5% to 118 MPa and 7.5%, respectively. Overall, IH treatment had a positive impact on interparticle bonding and mechanical properties.

Effect of deposition angle on the deposition rate, microstructure, electrical and optical properties of magnetron sputtered ZrB2 thin films

The microstructure and properties of thin films prepared by magnetron sputtering are usually sensitive to not only sputtering power and working pressure, but also the incident direction. In this work, ZrB2 thin films were prepared by DC magnetron sputtering at same sputtering parameters but substrate inclined from 0° to 30°. The deposition rate, microstructure, electrical and optical properties were investigated in details. XPS analysis demonstrates that all the prepared ZrB2 films are B-rich in compositions. Microstructure characterization shows the ZrB2 films deposited at bigger oblique angles are with better crystallization and bigger surface roughness, the former leads to the films with lower resistivity, the latter leads to the films with stronger absorbing ability in the UV–vis-NIR wavelength band. Adjusting substrate to a suitable oblique angle is a promising method to achieve higher quality ZrB2 films..

PBF (Powder Bed Fusion)와 DED (Directed Energy Deposition)의 연속 공정으로 적층제조된 630 스테인레스강의 마모 거동에 관한 연구

Hybrid additive manufacturing (AM) refers to a combination of two metal AM techniques: material deposition by powder bed fusion (PBF) and additional building by directed energy deposition (DED). This study focused on different characteristics in accordance with relative deposition directions of PBF and DED during hybrid AM production. Characteristics of the sample fabricated by hybrid AM (i.e., hybrid sample) were compared with those of the sample fabricated by PBF or DED. Ferrite was dominant in the microstructure of PBF deposits with very fine retained austenite observed locally. In contrast, lath martensite and retained austenite were formed uniformly in the microstructure of DED deposits. Different microstructures in the two processes were attributed to differences of cooling rate. In DED deposits, microhardness was significantly decreased owing to a high retained austenite fraction. However, in the hybrid sample, microhardness was rapidly increased in the HAZ owing to aging heat treatment for long-term deposition. Principal wear mechanisms of PBF and DED samples were oxidative wear and plastic deformation, respectively.

Structural and morphological characteristics of nanocrystalline palladium deposits prepared from ammonia complex by electrodeposition technique

ABSTRACT The present work is focused on the eco-friendly electrodeposition of nanocrystalline palladium on the copper substrate using an ammonia complex for the replacement of gold. The detailed study on the electrodeposition of palladium prepared from ammonia complex and solution characteristics such as current efficiency and thickness of the film growth per hour was evaluated using Faraday’s law of electrolysis, and the quality of the deposits was observed by Field Emission Scanning Electron Microscopy (FESEM). The crystal structure orientation of the crystal and lattice parameters were analysed by X-ray diffraction and crystal sizes were calculated using the Debye–Scherrer equation. The deposits produced from gelatin-containing electrolyte showed the lowest crystal size which indicates that grain refinement was assisted by additives. The microstructures of the palladium deposits were determined by FESEM and the surface morphology of the palladium deposits was evaluated using AFM. The elemental composition and oxidation state of the palladium deposits were investigated by XPS. These results revealed the presence of additives giving smooth uniform homogenous surface morphology. Hence, gelatin served as a grain modifier.

Depletion zone in two-dimensional deposits of soft microgel particles

HypothesisMicrogels are a class of model soft colloids that act like surfactants due to their amphiphilicity and are spontaneously adsorbed to the fluid-air interface. Here, we exploit the surfactant-like characteristics of microgels to generate Marangoni stress-induced fluid flow at the surface of a drop containing soft colloids. This Marangoni flow combined with the well-known capillary flow that arises during the evaporation of a drop placed on a solid surface, leads to the formation of a novel two-dimensional deposit of particles with distinct depletion zones at its edge. ExperimentsThe evaporation experiments using sessile and pendant drops containing microgel particles were carried out, and the microstructure of the final particulate deposits were recorded. The kinetics of the formation of the depletion zone and its width is studied by tracking the time evolution of the microgel particle monolayer adsorbed to the interface using in situ video microscopy. FindingsThe experiments reveal that the depletion zone width linearly increases with droplet volume. Interestingly, the depletion zone width is larger for drops evaporated in pendant configuration than the sessile drops, which is corroborated by considering the gravitational forces exerted on the microgel assembly on the fluid-air interface. The fluid flows arising from Marangoni stresses and the effect of gravity provide novel ways to manipulate the self-assembly of two-dimensional layers of soft colloids.

Electrocatalytic Properties of Co3O4 Prepared on Carbon Fibers by Thermal Metal-Organic Deposition for the Oxygen Evolution Reaction in Alkaline Water Electrolysis.

Cobalt oxide (Co3O4) serves as a promising electrocatalyst for oxygen evolution reactions (OER) in water-electrolytic hydrogen production. For more practical applications, advances in dry-deposition processes for the high-throughput fabrication of such Co3O4 electrocatalysts are needed. In this work, a thermal metal-organic deposition (MOD) technique is developed to form Co3O4 deposits on microscale-diameter carbon fibers constituting a carbon fiber paper (CFP) substrate for high-efficiency OER electrocatalyst applications. The Co3O4 electrocatalysts are deposited while uniformly covering the surface of individual carbon fibers in the reaction temperature range from 400 to 800 °C under an ambient Ar atmosphere. It is found that the microstructure of deposits is dependent on the reaction temperature. The Co3O4 electrocatalysts prepared at 500 °C and over exhibit values of 355-384 mV in overpotential (η10) required to reach a current density of 10 mA cm-2 and 70-79 mV dec-1 in Tafel slope, measured in 1 M KOH aqueous solution. As a result, it is highlighted that the improved crystallinity of the Co3O4 electrocatalyst with the increased reaction temperature leads to an enhancement in electrode-level OER activity with the high electrochemically active surface area (ECSA), low charge transfer resistance (Rct), and low η10, due to the enhanced electrical conductivity. On the other hand, it is found that the inherent catalytic activity of the surface sites of the Co3O4, represented by the turnover frequency (TOF), decreases with reaction temperature due to the high-temperature sintering effect. This work provides the groundwork for the high-throughput fabrication and rational design of high-performance electrocatalysts.