Local Heating Effect Research Articles

Quantifying the Contribution of Hot Electrons in Photothermal Catalysis: A Case Study of Ammonia Synthesis over Carbon-supported Ru Catalyst.

Photothermal catalysis is one of the most promising green catalytic technologies, while distinguishing the effects of hot electrons and local heating remains challenging. Herein, we reported that the actual reaction temperature of photothermal ammonia synthesis over carbon-supported Ru catalyst can be measured based on Le Chatelier's principle, enabling the hot-electron contribution to be quantified. By excluding local heating effects, we established that the activation energy via photothermal catalysis was much lower than that of thermocatalysis (54.9 vs. 126.0 kJ mol-1), stemming from hot-electron injection lowering the energy barriers for both N2 dissociation and intermediates hydrogenation. Furthermore, hot-electron injection acted to suppress carbon support methanation, giving the catalyst outstanding operational stability over 1000 h. This work provides new insights into the hot-electron effects in ammonia synthesis, guiding the design of high-performance photothermal catalysts.

Quantifying the Contribution of Hot Electrons in Photothermal Catalysis: A Case Study of Ammonia Synthesis over Carbon‐supported Ru Catalyst

AbstractPhotothermal catalysis is one of the most promising green catalytic technologies, while distinguishing the effects of hot electrons and local heating remains challenging. Herein, we reported that the actual reaction temperature of photothermal ammonia synthesis over carbon‐supported Ru catalyst can be measured based on Le Chatelier′s principle, enabling the hot‐electron contribution to be quantified. By excluding local heating effects, we established that the activation energy via photothermal catalysis was much lower than that of thermocatalysis (54.9 vs. 126.0 kJ mol−1), stemming from hot‐electron injection lowering the energy barriers for both N2 dissociation and intermediates hydrogenation. Furthermore, hot‐electron injection acted to suppress carbon support methanation, giving the catalyst outstanding operational stability over 1000 h. This work provides new insights into the hot‐electron effects in ammonia synthesis, guiding the design of high‐performance photothermal catalysts.

Linear and nonlinear characterization of a broadband integrated Si-rich silicon nitride racetrack ring resonator for on-chip applications.

We demonstrate the linear and nonlinear characterization of a plasma-enhanced chemical vapor deposited silicon-rich silicon nitride (SRSN) racetrack ring resonator for on-chip applications within the telecommunication wavelength range. The SRSN waveguide parameters are optimized by employing the refractive index profile measured by ellipsometry to achieve flat dispersion in the telecom band. Furthermore, we measure the thermo-optic coefficient of the micro-resonator by analyzing the temperature-dependent transmission spectra and assess it to be 3.2825×10-5 ∘ C -1. Additionally, we study power-dependent transmission spectra to investigate the effect of local heating and nonlinear absorption. The power-dependent transmission spectra exhibit a blueshifting of the resonance peak in the visible and near-IR regions, which indicates the presence of nonlinear losses in that range. The power-dependent transmission spectra almost remain unchanged in the telecom band, revealing the absence of nonlinear losses and excellent thermal stability in that wavelength range. Our experimental results reveal that the SRSN-based structure can be employed potentially to realize linear and nonlinear applications in the telecom band.

Effect of Local Heat and Cold Application for Pentavalent Vaccine Injection Pain in Infants

Effect of Local Heat and Cold Application for Pentavalent Vaccine Injection Pain in Infants

Integrated transparent surface acoustic wave technology for active de-fogging and icing protection on glass

There have been great concerns on poor visibility and hazardous issues due to fogging and ice/frost formation on glass surfaces of windshields, windows of vehicles/airplanes, and solar panels. Existing methods for their monitoring and removal include those active ones (such as using resistance heating) or passive ones (such as using surface icephobic treatments), which are not always applicable, effective or reliable. In this study, we proposed a novel strategy by implementing transparent thin film surface acoustic wave (SAW) devices by directly coating ZnO films onto glass substrate and studied their de-fogging, active anti-icing and de-icing mechanisms using the SAW technology. Effects of powers and wavelengths of SAW devices were investigated and influences of acousto-heating and surface hydrophobic treatments were evaluated. Results showed that de-fogging time was dramatically decreased with the increase of SAW powers when the thin film-based SAW devices were exposed to humid air flow for different durations. The icing accretion was significantly delayed under the applied SAW agitation, and SAW application has also effectively promoted de-icing on glass substrate, due to the interfacial nanoscale vibration and localized heating effect.

Local wall heating effects on aeroacoustic field radiated by an isolated square cylinder in a laminar flow

The aim of this work is to gain an insight on the effect of the wall heating on the aeroacoustic sound radiated by bluff bodies in laminar flows. In particular, the local thermal treatment of the wall boundary was investigated as a possible method for active controlling the emitted noise. This technique was studied performing direct numerical simulations of the aeroacoustic noise produced by an isolated square cylinder operating at a Reynolds and Mach numbers equal to 150 and 0.2, respectively. In the considered case, the Karman vortex street deriving by the flow/cylinder interaction, produces a lift and drag pulsation on the body surface, leading to a dipolar-like noise emission. In this context, different local thermal fluxes were applied to the cylinder wall in order to reduce its aerodynamic forces fluctuation and, consequently, the associated pressure disturbance that produces the radiated sound. The computations are performed using an OpenFOAM solver that adopts an explicit Runge-Kutta scheme for time integration and a second-order, energy conserving scheme for the convective part of the Eulerian flux. Moreover, the spurious numerical waves reflections at the far-field boundary are damped adopting a sponge-layer approach.

Water State-Driven Catalytic Hydrolysis of Ammonia Borane on Cu3P-Carbon Dot-Cu Composite.

Hydrogen production from ammonia borane (AB) is usually governed by water activation, which is not only energy-intensive but also requires expensive and complicated catalysts. We here propose an integrated photocatalytic-photothermal system that dramatically improves water activation and lowers the transport resistance of H2 by means of intermediate state water evaporation. This system is constructed by covering nanocomposites (Cu3P-carbon dots-Cu) upon vertically aligned acetate fibers (VAAFs). As a result of superior hydration effect of VAAFs and local photothermal heating for rapid water evaporation, its hydrogen production efficiency from AB hydrolysis reaches over 10 times the particulate suspension system under solar irradiation. Mechanism analysis reveals that the rapid vaporization of intermediate water promotes the cleavages of O-H bonds in bound water and the adsorption reaction of AB and water molecules at active sites. Therefore, this work provides a novel approach to optimize catalytic reaction in thermodynamics and kinetics for the hydrolysis of AB.

Photothermal Surface Heating Membrane Distillation Using 3D-Printed Ti3C2Tx MXene-Based Nanocomposite Spacers

To address the growing global need for freshwater, it has become essential to use nonpotable saline water. Solar membrane distillation is a potential desalination method that does not need conventional electricity and may cut water production costs. In this study, we develop a photothermal surface heating membrane distillation using a new class of photothermal spacers constructed with Ti3C2Tx MXene-based nanocomposites. In contrast to traditional membrane distillation, which utilizes energy-intensive bulk feed heating, solar-powered surface heating membrane distillation removes the external thermal energy input requirements, hence reducing operating costs significantly. In particular, three-dimensional (3D)-printing technology was used to fabricate the functional spacer, which allowed the design and materials to be fine-tuned per the needs of the process. Under solar illumination, the printed spacer can exhibit a localized photothermal conversion-driven heating effect near the surface of distillation membranes, which generates vapor pressure strong enough to operate distillation across membranes. Importantly, a two-dimensional Ti3C2Tx MXene with outstanding photothermal conversion efficiency and stability in hypersaline ionic solutions was incorporated into the 3D-printed spacers as the crucial nanofiller for imparting a local heating effect of feed. The fabricated nanocomposite spacers showed superior photothermal heating response under sunlight with an average permeate flux and energy conversion efficiency of 0.49 kg·m-2·h-1 and 30.6%, respectively. An enhancement in both photothermal efficiency and permeate flux was noticed as the amount of MXene nanosheets increased in the 3D-printed spacers. This study demonstrates the feasibility of using 3D-printed photothermal spacers for high-performance and sustainable surface heating membrane distillation, providing a promising avenue for further improvement with other photothermal nanofillers or spacer modifications.

Local passive heating administered during recovery impairs subsequent isokinetic knee extension exercise performance

BACKGROUND: Passive heating has attracted attention as a potentially promising recovery modality in sports. However, investigations of passive heating have yielded only inconsistent results for exercise performance. OBJECTIVE: To investigate the acute effects of local passive heating administered between repeated bouts of isokinetic exercise. METHODS: The experiment was a randomized crossover study. There was a total of three visits including a familiarization visit. During the remaining two visits, eleven healthy men performed three bouts of nine sets of isokinetic knee extensions using their dominant single-leg (30 repetitions/set, 180∘/sec). A 15 min recovery, during which a local passive heating pad at control (CON) or heating (HT) was applied to the rectus femoris, was afforded after the 3rd and 6th sets (Recovery 1 and 2). Isokinetic exercise performance, as assessed by peak torque, total work, and average power was analyzed using two-way repeated-measures ANOVA. RESULTS: Following Recovery 1 and 2, isokinetic exercise performance, as assessed by peak torque, total work, and average power was reduced in Set 4 (p< 0.001, p< 0.001, p= 0.080) and Set 7 (p< 0.001, p< 0.001, p= 0.009) in the HT group relative to the CON group. Electromyography analysis revealed that signal amplitude was lower in the HT group in Set 4 (p< 0.001) subsequent to Recovery 1, and that firing frequency was higher in Set 7 (p= 0.002) in the HT group after Recovery 2. Furthermore, EMG time-frequency maps from one representative participant showed that following Recovery 1 and 2 peak energy decreased during the first five repetitions in Set 4 and 7. CONCLUSIONS: Local passive heating administered during recovery decreased subsequent performance of isokinetic knee extensors, muscle activation ability and increased firing frequency maintaining force output. Therefore, local passive heating is not an appropriate acute recovery strategy for isokinetic exercises.

Coupling between Pyroelectricity and Built-In Electric Field Enabled Highly Sensitive Infrared Phototransistor Based on InSe/WSe2/P(VDF-TrFE) Heterostructure

The assorted utilization of infrared detectors induces the demand for more comprehensive and high-performance electronic devices that work at room temperature. The intricacy of the fabrication process with bulk material limits the exploration in this field. However, two-dimensional (2D) materials with a narrow band gap opening aid in infrared (IR) detection relatively, but the photodetection range is narrowed due to the inherent band gap. In this study, we report an unprecedented attempt at the coordinated use of both 2D heterostructure (InSe/WSe2) and the dielectric polymer (poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE)) for both visible and IR photodetection in a single device. The remnant polarization due to the ferroelectric effect of the polymer dielectric enhances the photocarrier separation in the visible range, resulting in high photoresponsivity. On the other hand, the pyroelectric effect of the polymer dielectric causes a change in the device current due to the increased temperature induced by the localized heating effect of the IR irradiation, which results in the change of ferroelectric polarization and induces the redistribution of charge carriers. In turn, it changes the built-in electric field, the depletion width, and the band alignment across the p-n heterojunction interface. Consequently, the charge carrier separation and the photosensitivity are therefore enhanced. Through the coupling between pyroelectricity and built-in electric field across the heterojunction, the specific detectivity for the photon energy below the band gap of the constituent 2D materials can reach up to 1011 Jones, which is better than all reported pyroelectric IR detectors. The proposed approach combining the ferroelectric and pyroelectric effects of the dielectric as well as exceptional properties of the 2D heterostructures can spark the design of advanced and not-yet realized optoelectronic devices.

Local heating and cooling with isometric exercise training as a strategy to improve size and performance

The purpose of this study was to explore the effects of local heating and cooling with isometric exercise training of upper arm and forearm. College-aged (n=12; 21±1 y) volunteers performed 4-wk isometric exercise training of the non-dominant arm (upper arm, isometric bicep curl; forearm, handgrip), while the dominant arm served as the control. Training was performed 3x/wk and consisted of 1 set of isometric handgrip and bicep curl until volitional exhaustion at 60% pre-training MVC for the forearm (handgrip) and 1RM for the upper arm (bicep curl). Randomized ordering of heating (40°C; 15 min) and cooling (12°C; 15 min) preceded each training session. Indirect assessment of muscle size (fat-free cross-sectional area [FFCSA]) was made before and after the training period via skin fold and limb circumference measures. Biceps 1RM increased significantly (p < 0.05) after the intervention in both conditions (trained: +6%; control: +7%), whereas only the control arm increased time to fatigue (+40%; p < 0.05). FFSCA of the upper arm remained unchanged (p>0.05) in both conditions. An effect of time was noted for forearm MVC (+8%; p < 0.05), while both groups increased (p < 0.05) time to fatigue (trained: +82%; control: +64%). A trend toward an effect of time was also noted for FFCSA of the forearm (+3%; p <.10). While the intervention employed here led to many notable adaptations, the thermal stress did not appear to exert a clear benefit. Coupled with the practicality and feasibility, improving size and performance in such a short time frame has therapeutic and ergogenic aid implications.

Effects of core air gaps and steel inserts on thermomechanical response of GFRP-balsa sandwich panels subjected to fire

Composite sandwich panels composed of a balsa core and glass fiber-reinforced polymer (GFRP) face sheets may offer attractive applications for building slabs and bridge decks. Such composite panels may contain air-filled gaps (caused by initial defects or damage) or through-thickness cracks and different types of metallic inserts (used for facilities and piping systems) in the balsa core. The fire performance of sandwich panels can be reduced by the local heating effects inside such air gaps and inserts. The thermomechanical response of GFRP-balsa sandwich panels comprising through-thickness air gaps or steel inserts, subjected to combined mechanical load and one-sided ISO 834 fire, were thus investigated by fire experiments and uncoupled thermal and mechanical numerical analysis. The results demonstrated that the shear resistance reduction of the core is not critical, while the moment resistance reduction can lead to panel failure. The propagation of a transverse tensile crack in the balsa core produced a similar moment resistance reduction to an air gap or steel insert. The air gaps and steel inserts charred the inner core zones and heated the cold face sheet above, leading to face wrinkling. The effects of air gaps and steel inserts remained local. Depending on their location in a panel, they may thus not exhibit significant effects on the whole structure. If they are placed on critical load paths however, e.g. in the vicinity of supports, they may cause collapse of the whole structure. Since the extension of transverse tensile cracks is not limited, they may also lead to an overall collapse.

Robust TiO2/CuS@TiO2 composites loaded on Ti mesh with outstanding stability and photothermal effects for the enhanced photo-degradation of organic pollutions in a flowing device

A scalable strategy with commercial feasibility was developed to in situ generate TiO2 nanowires/amorphous CuS@TiO2 nanolayer (TiO2/CuS@TiO2) composites on the surface of titanium mesh through a sequent hydrothermal method, successive ionic layer adsorption and reaction (SILAR), and atomic layer deposition (ALD) techniques. The TiO2/CuS@TiO2 composites could respectively harness the incident light with different spectra at the photothermal center (CuS, visible and near-infrared light) and photocatalytic center (TiO2, UV and visible light), which leads to the effective utilization of the solar energy. Benefiting from the CuS photothermal-induced local heating effect of CuS, the adjacent micro-zone temperature could be elevated and the activation energy barrier could be reduced by 10.5 kJ mol−1, which promotes the activation of surface lattice oxygen and dissolved oxygen in the photocatalytic process. Meanwhile, the ALD generated TiO2 nanolayer could both serve as reactive centers but also protecting armor for the CuS, which prohibited the peeling and oxidation of the thermal centers, leading to a high stability of the photocatalyst, which exhibits no obvious fading after 20-cycle reuse. A flow reactor was conceived and made by 3D print and the Ti-mesh based photocatalyst was integrated, which demonstrates high photocatlytic performances, manifesting its great potential for large-scale water treatment.

Numerical Studies of Magnetic Reconnection and Heating Mechanisms for the Ellerman Bomb

An Ellerman Bomb (EB) is a kind of small scale reconnection event, which is ubiquitously formed in the upper photosphere or the lower chromosphere. The low temperature (<10,000 K) and high density (∼1019–1022) plasma there makes the magnetic reconnection process strongly influenced by partially ionized effects and radiative cooling. This work studies the high β magnetic reconnection near the solar temperature minimum region based on high-resolution 2.5D magnetohydrodynamics simulations. The time-dependent ionization degree of hydrogen and helium are included to realize more realistic diffusivities, viscosity and radiative cooling in simulations. Numerical results show that the reconnection rate is smaller than 0.01 and decreases with time during the early quasi-steady stage, then sharply increases to a value above 0.05 in the later stage as the plasmoid instability takes place. Both the large value of η en (magnetic diffusion caused by the electron-neutral collision) and the plasmoid instability contribute to the fast magnetic reconnection in the EB-like event. The interactions and coalescence of plasmoids strongly enhance the local compression heating effect, which becomes the dominant mechanism for heating in EBs after plasmoid instability appears. However, the Joule heating contributed by η en can play a major role to heat plasmas when the magnetic reconnection in EBs is during the quasi-steady stage with smaller temperature increases. The results also show that the radiative cooling effect suppresses the temperature increase to a reasonable range, and increases the reconnection rate and generation of thermal energy.

Effect of local heating by ultrashort pulsed laser on Fe–Si–B–Cr amorphous alloys and its influence on blanking machinability

We propose a novel blanking method to improve the machinability of amorphous alloys by taking advantage of changes in mechanical properties during local heating. The local heating is achieved through an ultrashort pulsed laser with a low thermal effect, allowing us to control the size and structure of heat-affected zones by adjusting laser power, pulse width, and shot numbers. This method hence causes phase transformation only in the blanking area. Namely, heat storage effects increased with a prolonged ablation process, and crystallization was observed at a repetition rate of 200 kHz or more. A fully crystallized microstructure, which formed at elevated temperatures, was seen at the center of the laser irradiation, while, as the distance from the irradiation point increased, small crystallites are found to disperse in the amorphous matrix. In addition, a thin crystalline phase appeared on the surface layer of the crystallized region. In general, the locally heated area was embrittled by the aforementioned structural changes, and consequently, the blanking resistance decreased with an increase in the crystallized area. Yet, it was found that laser irradiation which did not bring about crystallization also led to a decrease in the blanking resistance, showing that thermal effects below the crystallization temperature are still effective in reducing the blanking resistance. Additionally, the blanked cross-section of the locally heated specimen showed good surface quality without defects such as a large shear droop, which often occurs when punching amorphous alloys.

Surface-governed deformation mechanisms in sub-20-nm metallic crystals stimulated by electrical loading

Metal nanocrystals have been shown to present two sorts of antithetical mechanical behaviors during mechanical tests, that is, “smaller is stronger” and “smaller is weaker”. Dislocation-starvation induced strengthening and surface diffusion induced softening are revealed as two main mechanisms that govern such behaviors. However, the competition between these two mechanisms, as well as their relationship with temperature, is still unclear. To probe into this issue, we here perform an investigation on sub-20-nm Au and Co nanocrystals using an electrical loading-coupled transmission electron microscopy, as the electrical loading can create an adjustable local heating effect, providing variable conditions for testing temperature-related competitions between displacive and diffusional events. It is found that surface diffusion is much more sensitive to temperature than dislocation activities. Apparent transitions of deformation mechanisms are observed when surface diffusion is energetically activated or inhibited. Surface curvature acts as a stimulus or mediator to atom diffusion, generating double-edged impacts on the nucleation of dislocation slip. At elevated temperatures (i.e. high electrical loading), the metal nanocrystals present liquid-like behaviors. Their surfaces can consecutively reshape when surface diffusion dominates; otherwise, shape transformations take place in a collapse-and-reconstruction manner.

InP- and GaAs-Based Photonic Power Converters Under O-Band Laser Illumination: Performance Analysis and Comparison

Photonic power converters (PPCs), which convert narrow-band light to electricity, are essential components in power-by-light systems. When designed for telecommunications wavelengths such as the O-band, near 1310 nm, the devices are well-suited to power-over-fiber applications. Despite the potential for very high power conversion efficiencies ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathbf {&gt;50\%}$</tex-math></inline-formula> ), PPCs can be adversely affected by high-intensity nonuniform illumination conditions. In this work, we characterized two O-band PPC designs based on: high-quality InGaAsP absorber material lattice-matched to an InP substrate, and metamorphic InGaAs absorber material lattice-mismatched to a GaAs substrate, a more cost-effective and scalable alternative. We measured each device under O-band laser illumination with five beam profiles having peak-to-average ratios ranging from 2 to 11. Both devices were insensitive to the beam uniformity for input illumination with average irradiance below 2 W/cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathbf {^{2}}$</tex-math></inline-formula> over their 5.4-mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathbf {^{2}}$</tex-math></inline-formula> active areas, but exhibited better open-circuit voltages under larger, more uniform illumination profiles at higher incident powers. Measured efficiencies reached 52.8% and 48.7% for the lattice-matched and mismatched devices, respectively. Distributed circuit modeling results suggested that both lateral conduction losses and localized heating effects were responsible for the measured dependence on beam-size. Our work demonstrates the potential for O-band PPCs, presenting two highly efficient designs suitable for powering devices requiring <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathbf {\lesssim 250}$</tex-math></inline-formula> mW, with an appropriate illumination profile.

Droplet transportation on photosensitive lubricant-impregnated slippery surfaces in response to the light induced Marangoni effect and asymmetrical wetting ridges.

Flexible control of droplet transportation is crucial in various applications but is constrained by liquid-solid friction. The development of biomimetic lubricant-impregnated slippery surfaces provides a new solution for flexible manipulation of droplet transportation. Herein, a light strategy is reported for flexibly controlling droplet transportation on photosensitive lubricant-impregnated slippery surfaces. Owing to the localized heating effect of a focused laser beam via photothermal conversion, the resultant thermal Marangoni flow and horizontal component of the surface tension associated with the asymmetric wetting ridges are together responsible for actuating droplet transportation. It is found that the asymmetry of the wetting ridge is dominated by the thickness of the infused oil layer, which directly affects the droplet transportation. The feasibility of this light strategy is also demonstrated by uphill movement, droplet coalescence, and chemical reaction. This study provides a new design for potential applications in open droplet microfluidics, analytical chemistry, diagnosis, etc.

Induction heating enables efficient heterogeneous catalytic reactions over superparamagnetic nanocatalysts

Most catalytic processes are achieved by heating the whole reaction systems including the entire reactor, substrate and solvent, which leads to energy loss and obvious heat transfer limits. In this study, induction heating was employed to boost the catalytic Suzuki-Miyaura cross-coupling reactions by using conductive superparamagnetic microspheres with loaded Pd nanoparticles as heterogeneous catalysts. It was found that, at the same apparent reaction temperatures, the reactions by adopting the induction heating all exhibit better catalytic performance with higher conversion and yield, as compared to the reactions using conventional joule heating. The improvement is mainly attributed to the localized heating effect endowed by high efficiency of the heat transfer from the heat source to catalytic sites, which dissipates the electromagnetic energy through Néel relaxation mechanism. Moreover, it has be found that the reactions have been largely accelerated, resulting in much shorter reaction time required to approach a given value of reactant conversion. These results indicate that the unique heating method based on the superparamagnetic nanomaterials as both the inductive component and catalyst support holds a promising application for fast and efficient heterogeneous catalytic process, and exhibits potential for improving energy transfer efficiency and reducing the side reactions attributed to the uneven temperature profile.

Plasma Oxidation of Copper: Molecular Dynamics Study with Neural Network Potentials.

The formation of thin oxide films is of significant scientific and practical interest. In particular, the semiconductor industry is interested in developing a plasma atomic layer etching process to pattern copper, replacing the dual Damascene process. Using a nonthermal oxygen plasma to convert the metallic copper into copper oxide, followed by a formic acid organometallic reaction to etch the copper oxide, this process has shown great promise. However, the current process is not optimal because the plasma oxidation step is not self-limiting, hampering the degree of thickness control. In the present study, a neural network potential for the binary interaction between copper and oxygen is developed and validated against first-principles calculations. This potential covers the entire range of potential energy surfaces of metallic copper, copper oxides, atomic oxygen, and molecular oxygen. The usable kinetic energy ranges from 0 to 20 eV. Using this potential, the plasma oxidation of copper surfaces was studied with large-scale molecular dynamics at atomic resolution, with an accuracy approaching that of the first principle calculations. An amorphous layer of CuO is formed on Cu, with thicknesses reaching 2.5 nm. Plasma is found to create an intense local heating effect that rapidly dissipates across the thickness of the film. The range of this heating effect depends on the kinetic energy of the ions. A higher ion energy leads to a longer range, which sustains faster-than-thermal rates for longer periods of time for the oxide growth. Beyond the range of this agitation, the growth is expected to be limited to the thermally activated rate. High-frequency, repeated ion impacts result in a microannealing effect that leads to a quasicrystalline oxide beneath the amorphized layer. The crystalline layer slows down oxide growth. Growth rate is fitted to the temperature gradient due to ion-induced thermal agitations, to obtain an apparent activation energy of 1.0 eV. A strategy of lowering the substrate temperature and increasing plasma power is proposed as being favorable for more self-limited oxidation.