Interfacial Transfer Research Articles

Interfacial Stress Transfer and Fracture in van der Waals Heterostructures.

Artificially stacking 2D materials (2DMs) into vdW heterostructures creates materials with properties not present in nature that offer great potential for various applications such as flexible electronics. Properties of such stacked structures are controlled largely by the interfacial interactions and the structural integrity of the 2DMs. In spite of their crucial roles, interfacial stress transfer and the failure mechanisms of the vdW heterostructures, particularly during deformation, have not been well addressed so far. In this work, the interfacial stress transfer and failure mechanisms of a MoS2/graphene vdW heterostructure are studied, through the strain distributions both laterally in individual 2DMs and vertically across different 2DMs revealed in-situ. The fracture of the MoS2 and the associated states of stress and strain are monitored experimentally. This enables various interfacial properties, such as the interfacial shear strength and interfacial fracture energy, to be estimated. Based only on the measured strength and interfacial properties of a single vdW heterostructure, a failure criterion is proposed to predict the failure mechanisms of similar vdW heterostructures with any lateral dimensions. This work provides an insight to the deformation micromechanics of vdW heterostructures that are of great value for their miniaturization and applications, especially in flexible electronics.

Porous titanium/hydroxyapatite interpenetrating phase composites with optimal mechanical and biological properties for personalized bone repair

This study introduces the first fabrication of porous titanium/hydroxyapatite interpenetrating phase composites achieved through an innovative processing method. The approach combines additive manufacturing of a customized titanium skeleton with the infiltration of an injectable hydroxyapatite foam, followed by in situ foam hardening at physiological temperature. This biomimetic process circumvents ceramic sintering and metal casting, effectively avoiding the formation of secondary phases that can impair mechanical performance. Hydroxyapatite foams, prepared using two foaming agents (polysorbate 80 and gelatine), significantly reinforce the titanium skeleton while preserving the microstructural characteristics essential for osteoinductive properties. The strengthening mechanisms rely on the conformation of the foams to the titanium surface, thereby enabling a stable mechanical interlocking and effective interfacial stress transfer. This, combined with the mechanical constriction of phases, enhances damage tolerance and mechanically reliability of the interpenetrating phase composites. In addition, the interpenetrating phase composites feature a network of concave pores with an optimal size for bone repair, support human osteoblasts proliferation, and exhibit mechanical properties compatible with bone, offering a promising solution for the efficient and personalized reconstruction of large bone defects. The results demonstrate a significant advancement in composite fabrication, integrating the benefits of additive manufacturing for bone repair with the osteogenic capacity of calcium phosphate ceramics.

Straightforward electroanalytical sensing of nitrate in cyanobacteria growth media at electrified liquid-liquid interface

Nitrate is one among the necessary substance in the biosphere as its presence is pivotal to ensuring healthy vegetation and human health while its excess causes serious adversities. In this work, we utilized the electrified liquid-liquid interface (eLLI) and voltammetry to develop an alternative approach that enables onsite periodic monitoring of nitrate ions in cyanobacteria growth medium. The signal attributed to nitrate detection was directly related to its interfacial ion transfer behavior and not the redox properties. The ion transfer voltammograms of nitrate at eLLI delivered useful analytical parameters of linear detection range from 20 to 500 μM paired with detection and quantification limits of 1.5 and 14.6 μM, respectively. Further, the influence of chloride ions, and other anionic species present in the algae grow media were studied towards the determination of nitrates. We also optimized an in-situ chemical precipitation strategy to eliminate the influence of chloride ions that significantly improved the accuracy of the eLLI-based nitrate sensor. eLLI-based nitrate sensor delivered a remarkable analytical performance to determine nitrate levels in Z8 medium composed of nitrate and other nutrients (medium serving as the optimal environment for algae growth). eLLI based nitrate sensor was successful towards periodic monitoring of nitrate levels in Microcystis aeruginosa cyanobacteria samples cultured in Z8 medium.

Iron single atoms and nitrogen vacancies on graphitic carbon nitride synergically shallowing deep electron traps towards efficient photocatalytic ozonation

The coupling of photocatalysis and ozonation has been approved a very efficient strategy for hydroxyl radicals (•OH) production and wastewater decontamination, yet it remains challenging to enrich surface-reaching charges around reaction centers to accelerate this process. This paper explored the strategy of single-atoms (SAs) modification and defects control, aiming to enhance the activity of graphite carbon nitride (CN) in the visible light photocatalytic ozonation. It was found that the presence of iron SAs on CN greatly altered the impact of nitrogen vacancies (NVs), which behaved as recombination centers of photogenerated charge carriers and deteriorated activity of CN, while positively promoting the separation and migration of photogenerated carriers in the case for Fe-CNV (consist of iron SAs and NVs) catalysts. Based on photoluminescence (PL) emission, time-resolved PL spectra, ultrafast transient absorption spectroscopy and first-principles calculations, we found that adjacent iron SAs revived electrons trapped at NVs by elevating their energy level and mediating their interfacial transfer, leading to the decreased loss during electron transfer. This finding demonstrates the feasible tailor of energy level alignment for defect states to shallow deep electron traps.

Coupled Wall Boiling and Population Balance Model for High Void Fraction Flows Under Sub-Cooled Nucleate Boiling Regime: Model Development and Validation

Abstract The subcooled flow boiling of water in a vertical annulus channel is studied numerically at low-pressure conditions. The two-fluid model is developed with flow-regime dependent interfacial transfers for mass, momentum, and energy using the algebraic interfacial area density (AIAD) framework. A discrete population balance model is used to mechanistically determine the vapor bubble diameter in the flow channel by considering the bubble aggregation and breakup effects. Energy balance at the heated wall for the subcooled nucleate boiling is handled using a suitable wall boiling model. A coupling is achieved between the discrete population balance and the wall boiling model for the nucleation and the growth rate of the vapor bubbles along the heated wall. The developed model simulates the reference experimental cases of flow boiling in a vertical channel for various flow and thermal conditions. At low wall heat flux, the wall boiling generates vapor bubbles near the heated wall and within the bubbly flow regime. With an increase in the wall heat flux, the aggregation and evaporation cause the formation of larger bubbles, which progress toward the flow channel core region, a phase that is representative of the transitional flow regime. The model's capability to predict such flow regime transition is validated with the experimental results. The bubble aggregation is found to be dominant compared to the breakup, and thus, proper choice of the aggregation factor is important for the accurate prediction of vapor parameters for the subcooled flow boiling at low-pressure conditions.

Multiphase nitrosation based on N2O3 intermediate and process intensification in a microflow reactor

Nitrosation of alcohols with nitrous acid is widely used to prepare alkyl nitrites, but the reaction mechanism and formation pathways of gaseous side products remain unclear. Here, we propose a nitrosation mechanism based on a highly reactive intermediate, dinitrogen trioxide (N2O3). The N2O3-based mechanism shows a lower energy barrier than the previously reported acid-catalyzed and nitrosyl cation mechanism. Furthermore, a microfluidic platform was established to investigate the gas–liquid-liquid reaction system and characterize the gas holdup of the multiphase reaction system. The results suggest that the reaction rate and selectivity primarily depend on the interfacial mass transfer of N2O3 between the aqueous-organic and gaseous-organic phases. A tubular microreactor was employed to intensify the nitrosation process of isopropanol. In contrast to the batch process operated by adding reactants dropwise in several hours, the product yield of 95 % can be achieved in a residence time of only 10 s in the microflow reactor.

Dendrite-free zinc metal anode for long-life zinc-ion batteries enabled by an artificial hydrophobic-zincophilic coating

Considering the desired energy density, safety and cost-effectiveness, rechargeable zinc-ion batteries (ZIBs) are regarded as one of the most promising energy storage units in next-generation energy systems. Nonetheless, the service life of the current ZIBs is significantly limited by rampant dendrite growth and severe parasitic reactions occurring on the anode side. To overcome these issues caused by poor interfacial ionic conduction and water erosion, we have developed a facile strategy to fabricate a uniform zinc borate layer at the zinc anode/electrolyte interface (ZnBO). Such protective layer integrates superhydrophobic-zincopholic properties, which can effectively eliminate the direct contact of water molecules on the anode, and homogenize the interfacial ionic transfer, thereby enhancing the cyclic stability of the zinc plating/stripping. As a result, the as-prepared ZnBO-coated anode exhibits extended lifespan of 1200 h at 1 mA cm−2 and demonstrates remarkable durability of 570 h at 20 mA cm−2 in Zn||Zn symmetric cells. Additionally, when coupled to an NH4V4O10 (NVO) cathode, it also delivers a superior cyclability (203.5 mAh/g after 2000 cycles at 5 A/g, 89.3 % capacity retention) in coin full cells and a feasible capacity of 2.5 mAh at 1 A/g after 200 cycles in pouch full cells. This work offers a unique perspective on integrating hydrophobicity and zincophilicity at the anode/electrolyte interface through an artificial layer, thereby enhancing the cycle lifespan of ZIBs.

Unraveling the Microstructure‐Property Relationship of Fe Single‐Atoms via Introducing Asymmetric P‐Coordination for Photocatalytic Hydrogen Evolution

AbstractThe local atomic environments of single‐atom photocatalysts play a decisive role in determining the solar‐to‐hydrogen energy conversion efficiency. However, controllably modulating the microstructure of single‐atom sites to enhance catalytic activity and deeply understanding the structure‐property relationship remain great challenges. Herein, electron‐rich P atoms are introduced to accurately regulate the local coordination environment and electronic configuration of Fe single atoms and construct a unique asymmetrical FeN3P2 motif into carbon nitride (FeN3P2‐CN) for significantly improving the photocatalytic H2 evolution activity and stability. Specifically, in the absence of noble metal cocatalyst and photosensitizer, the FeN3P2‐CN achieves a remarkable H2 evolution rate of 2668.5 µmol g−1 h−1 under visible light irradiation (λ > 420 nm), more than 105 times higher than that of unregulated FeN4 sample. Systematic characterizations and theoretical calculations unveil that the FeN3P2 single‐atom sites not only significantly broaden the photoabsorption region and facilitate the charge separation and interfacial transfer, but also efficiently promote adsorption and activation of H2O. This work paves a promising pathway to design novel single‐atom photocatalysts at the atomic level for achieving highly efficient water‐splitting performance.

Revisiting the sequential evolution of sizing agents in CFRP manufacturing to guide cross-scale synergistic optimization of interphase gradient and infiltration

Using sizing agents instead of various nanoparticles to modify carbon fibers is widely recognized as the most practical approach to address processing issues and improve interfacial properties in carbon fiber reinforced polymer composites. However, a limited understanding of sizing agent evolution during composite manufacturing hinders comprehensive theoretical guidance for sizing treatment, thereby limiting further enhancement of composite performance. Here we disentangled the sizing agents into chemical anchoring and physical adsorption components, and elucidated the sequential wetting, diffusion, and crosslinking evolution processes of sizing agents across scales. By manipulating the proportion of chemical anchoring and physical adsorption in the sizing agents, the interfacial modulus gradient and infiltration efficiency were synergistically optimized. Consequently, significant improvements of 26.2 % in interfacial shear strength (IFSS) and 52.9 % in transverse fiber bundle tensile (TFBT) strength were achieved, indicating enhanced interfacial stress transfer and reduced internal defects in the composites. In summary, this work revisited the cross-scale evolution and mechanism of sizing agents during composite manufacturing, and thus provided a new paradigm for optimizing composite performance.

An investigation of anisotropy in the bubbly turbulent flow via direct numerical simulations

We investigated the effects of bubble count, flow direction, and Eötvös number on deformable bubbles in turbulent channel flow. For a given shear Reynolds number Re = 180 and fixed bubble volume fractions (1.263% and 2.525%), we conducted a series of direct numerical simulations using a coupled level-set and volume-of-fluid solver to evaluate their impact on bubble volume fraction distribution, velocity fields, and turbulence characteristics. Each aspect was studied based on the microscopic equations of two-phase flow, and the accuracy of the modeling terms used in current Reynolds-averaged Navier–Stokes equation (RANS) models was assessed. The influence on the anisotropic state was analyzed using the Lumley triangle, and the anisotropy of Reynolds stresses was captured through the exact balance equations. The results indicate that in upward flow, bubbles tend to accumulate near the wall, with smaller Eötvös numbers leading to closer proximity to the wall and greater attenuation of the liquid-phase velocity. This distribution enhances energy dissipation and turbulence isotropy. In downward flow, bubbles cluster in the channel center, generating additional pseudo-turbulence and attenuating energy in the buffer layer. Moreover, the interfacial transfer of turbulent energy, as currently modeled in RANS, is found to be inadequate for upward flows.

Interfacial crosslinking benzimidazolium enables eco-friendly inverted perovskite solar cells and modules

Interfacial engineering via controlled crosslinking at perovskite surface is of significance to address the interfacial loss in inverted perovskite solar cells (PSCs), while is unfortunately impeded by the unsatisfied interfacial charge extraction and transfer owing to the inherent low conductivity of the formed crosslinked network. We herein propose and validate a strategy of interfacial crosslinking benzimidazolium (ICB) that is capable of reducing the surface residual strain of perovskite and improving the interfacial carrier transfer, leading to a new benchmark of power conversion efficiency (PCE) up to 25.30 % in inverted PSCs, as well as 21.73 % in inverted PSC modules (6 × 6 cm²). Such the ICB network also results in sustainable PSCs and modules with superior stability even under various harsh conditions, e.g. suppressing lead leakage of PSCs with the rate of 83.6 %, maintaining the initial efficiency of 90 % after 1200 h of continuous heating at 85 °C, and 92.8 % of its pristine efficiency over 1200 h of continuous irradiation. We thus believe that present work demonstrates the potential of ionic molecules crosslinking at interfaces for high performance inverted PSCs.

Wafer-Scale Transfer of MXene Films with Enhanced Device Performance via 2D Liquid Intercalation.

Wafer-scale transfer processes of 2D materials significantly expand their application space in scalable microelectronic devices with excellent and tunable properties through van der Waals (vdW) stacking. Unlike many 2D materials, wafer-scale transfer of MXene films for vdW contact engineering has not yet been reported. With their rich surface chemistry and tunable properties, the transfer of MXenes can enable enormous possibilities in electronic devices using interface engineering. Taking advantage of the MXene hydrophilic surface, a straightforward, green, and fast process for the transfer of MXene films at the wafer scale (4-inch) is developed. Uniform vdW stacking of several types of large-area heterojunctions including MXene/MXene (Ti3C2Tx, Nb2CTx, and V2CTx), MXene/MoS2, and MXene/Au is further demonstrated. Multilayer support is applied to minimize damage or deformation in the transfer process of patterned Ti3C2Tx film. It allows us to fabricate thin film transistors and manipulate the MXene/MoS2 interface through the intercalation of various 2D liquids. Particularly noteworthy is the significant enhancement of the interfacial carrier transfer efficiency by ≈2 orders of magnitude using hydrogen iodide (HI) intercalation. This finding indicates a wide range of possibilities for interface engineering by transferring MXene films and employing liquid-assisted interfacial intercalation.

Dynamical Adsorption Behavior Prediction of Dried Tobacco Leaf Heterogeneous Interfaces through Simulation and Image Recognition Techniques.

The process of spraying water and flavorings on dry tobacco is an important factor in the industrial environment and product quality. Tobacco as a complex porous fiber material, the interfacial transfer process of water is complex. In this study, machine learning and image recognition techniques were utilized to quickly obtain the structural parameters of the tobacco surface and construct a cellular structure model of the tobacco surface. In situ observation of the droplet impact spreading process was carried out using a high-speed camera to explore the droplet dissipation dynamics on different surfaces. And the competing processes of droplet wetting and evaporation under the influence of surface microstructure were determined by combining experimental studies and finite element simulation calculations. Based on the characteristics of tobacco pore size distribution, the infiltration under gas-liquid two-phase action was transformed into single-phase flow transfer under capillary force, and the continuous droplet infiltration process was simulated. A parallel artificial membrane permeability measurement method of bionic tobacco waxy layer was constructed for the screening of spray dosing copenetrant. This study brings new insights into the wetting of porous fibrous materials and is important for exploring the wetting process and additive development process influenced by the microstructure.

Cascading CRISPR/Cas and Nanozyme for Enhanced Organic Photoelectrochemical Transistor Detection with Triple Signal Amplification.

Innovative signal amplification and transduction play pivotal roles in bioanalysis. Herein, cascading CRISPR/Cas and the nanozyme are integrated with electronic amplification in an organic photoelectrochemical transistor (OPECT) to enable triple signal amplification, which is exemplified by the miRNA-triggered CRISPR/Cas13a system and polyoxometalate nanozyme for OPECT detection of miRNA-21. The CRISPR/Cas13a-enabled release of glucose oxidase could synergize with peroxidase-like SiW12 to induce catalytic precipitation on the photogate, inhibiting the interfacial mass transfer and thus the significant suppression of the channel current. The as-developed OPECT sensor demonstrates good sensitivity and selectivity for miRNA-21 detection, with a linear range from 1 fM to 10 nM and an ultralow detection limit of 0.53 fM. This study features the integration of bio- and nanoenzyme cascade and electronic triple signal amplification for OPECT detection.

Multiple strategies enhance visible-light photocatalytic degradation levofloxacin of Fe-doped MOF/AgCl Z-scheme heterojunction composites based on pyrazole carboxylic ligand

The construction of visible-light catalysts to degrade water pollutants is significant in environmental governance and solar energy conversion. In this work, a novel Zn-MOF with unsaturated coordination sites was constructed using 1-(Carboxymethyl)-pyrazole-4-carboxylic acid as the organic ligand. Its crystal structure was studied through single crystal X-ray diffraction. To enhance visible light catalytic performance, ZnFe-MOF/AgCl-x Z-scheme heterojunction composites were constructed. The optimized ZnFe-MOF/AgCl-50 material exhibits excellent photocatalytic performance, which can degrade 90.33 % of levofloxacin in 21 min. The results indicate that Fe doping and the construction of the ZnFe-MOF/AgCl-x Z-scheme heterojunction not only broaden the responsive range to visible light, but also effectively promote the internal and interfacial charges transfer efficiency, leading to a superior catalytic performance. In addition, the Ag nanoparticles (NPs) generated during the photocatalytic process can serve as a bridge, achieving rapid charge transfer in Z-scheme heterojunction. This work can offer an innovative perspective for the development of novel and efficient MOF-based Z-scheme heterojunction photocatalysts for wastewater treatment applications.

Polyaniline as a solid-state charge conductor for enhanced photocatalytic hydrogen production and value-added disulfide synthesis

Efficient transfer and maximal utilization of photogenerated electrons and holes in photocatalytic processes, along with the simultaneous production of hydrogen and high-value chemicals, represent a promising approach for effective solar energy utilization. Herein, polyaniline (PANI) was employed as a charge conductor to enhance the heterojunction structure between g-C3N4 and CdS, thereby facilitating the efficient interfacial transfer of photogenerated carriers. The obtained composite has demonstrated outstanding photocatalytic performance in both water splitting for hydrogen production and the dehydrogenation coupling of thiols. The hydrogen evolution efficiency of g-C3N4-PANI-CdS composite in water splitting is 41.67 times higher than that of the original g-C3N4. Additionally, the sample exhibits efficient splitting and re-polymerization capabilities for 4-methoxythiophenol (4-MTP), achieving the efficient hydrogen production and bis (4-methoxyphenyl) disulfide (4-MPD) synthesis concurrently. Comprehensive characterization methods confirm that PANI acts as a highly conductive layer, accelerating rapid charge transfer and separation at the interface between g-C3N4 and CdS, significantly improving the utilization of surface active sites. This study provides valuable insights for the future advancements in photocatalytic hydrogen generation and disulfides synthesis.

Highly selective photocatalytic CO2 reduction into C2H4 enabled by metal–organic framework-derived catalysts with high Cu+ content

The highly selective conversion of CO2 into valuable C2H4 is a highly important but particularly challenging reaction. Herein, the metal–organic frameworks MOF-74(Cu) with infinite Cu(II)-O chains and Cu-BTC (BTC=benzene-1,3,5-tricarboxylate) with paddle-wheel binuclear Cu(II) clusters are used as precursors. These MOFs are reduced by NaBH4 to obtain Cu0/Cuδ+-based photocatalysts denoted as R-MOF-74(Cu) and R-Cu-BTC, respectively. Significantly, R-MOF-74(Cu) achieves a high selectivity of 90.2 % for C2H4 with a yield rate of 6.5 μmol g−1 within 5 h due to its high Cu+ content. To the best of our knowledge, this C2H4 product selectivity is a record high among all the photocatalysts reported so far for photocatalytic CO2 reduction. In contrast, R-Cu-BTC only forms CO as a product with a cumulative yield of 0.7 μmol g−1 within 5 h. Photoelectrochemical characterization and electron paramagnetic resonance results show that R-MOF-74(Cu) has low interfacial transfer resistance, high photogenerated electron separation efficiency, and excellent CO2 activation and water oxidation performance. In addition, in situ Fourier transform infrared spectroscopy is used to determine the possible reaction pathway from CO2 to C2H4 over R-MOF-74(Cu). This work demonstrates the great potential of MOF-derived photocatalysts for the conversion of CO2 into C2H4 and provides guidance for future photocatalyst development.

In Situ Photoreversible Tuning of Chemical Interface Damping in Single Gold Nanorods Through Cucurbit[8]uril-Based Host-Guest Interactions.

Chemical interface damping (CID) is a recently proposed plasmon-damping pathway based on the interfacial hot-electron transfer from metal to adsorbate molecules. However, the in situ reversible tuning of CID in single gold nanorods (AuNRs) has remained a considerable challenge. In this study, we used total internal reflection scattering microscopy and spectroscopy to investigate the CID induced by p-aminoazobenzene (p-AAB), which has fast photoisomerization characteristics, attached to single AuNRs. We demonstrated the in situ reversible tuning of CID in single AuNRs by switching between ultraviolet (UV, 365 nm) and visible (vis, 465 nm) irradiation to induce photoresponsive structural conversions between the cis and trans forms of p-AAB in ethanol, leading to different lowest unoccupied molecular orbital (LUMO) energies for both forms. The localized surface plasmon resonance (LSPR) line width was wide under vis irradiation but narrow under UV irradiation, indicating that hot electrons are more efficiently transferred to trans-p-AAB with a low LUMO energy level. We further investigated the in situ photoreversible tuning of CID by manipulating supramolecular host-guest interactions between cucurbit[8]uril (CB[8]) and p-AAB in the single AuNRs. Additionally, real-time in situ reversible tuning of CID in single AuNRs was achieved through photonic switching of the cis-trans forms of p-AAB inside CB[8]. The LSPR line width was narrow under vis irradiation but gradually widened under UV irradiation before narrowing again upon returning to vis irradiation, unlike the case with p-AAB only. These results can be ascribed to the fact that cis-p-AAB completely encapsulated within CB[8] in water is thermodynamically more favorable than trans-p-AAB. Therefore, we have discovered a new strategy for tuning the CID by performing p-AAB photoisomerization and adjusting the wavelength of incident light in single AuNRs. In addition, this study demonstrates that CID can be effectively applied to the development of biosensors to detect guest molecules and their structural changes inside the cavity of CB[8] in single AuNRs.

Surface Reconstruction-Induced Photocatalytic Methanol Reduction Reaction on a Rutile TiO2(001) Surface.

Photochemistry of methanol on TiO2 surfaces is of great importance both fundamentally and industrially. Methanol was previously reported only to occur photogenerated hole-participating oxidation reactions on TiO2 surfaces. Herein, we report that, upon UV light illumination, the methoxy species formed by methanol dissociation at the 5-fold coordinated Ti4+ sites (CH3O(a)Ti5c) of a reconstructed rutile TiO2(001)-(1 × 1) surface also undergoes the C-O bond cleavage into methyl fragments mediated by photogenerated electrons, in addition to the well-established photogenerated hole-participating oxidation reactions. Upon subsequent heating, the resulting methyl species undergoes hydrogenation and coupling reactions into methane and ethane, respectively. Accompanying theoretical calculations showed that the lowest unoccupied molecular orbital (LUMO) of CH3O(a)Ti5c is localized almost at the conduction band minimum of the CH3O-adsorbed reconstructed rutile TiO2(001)-(1 × 1) surface, indicating the likely TiO2 → CH3O(a)Ti5c interfacial photoexcited-electron transfer. These results greatly broaden the photochemistry of methanol on TiO2 surfaces and demonstrate a photocatalytic methanol-to-hydrocarbon reaction route.

Ion Transfer Kinetics at the Tungsten Oxide Interface

Investigating the kinetics of interfacial ion transfer is imperative for the enhancement of electrochemical energy storage technologies, such as cation batteries. Consequently, we study the enigmatic proton transfer mechanisms that occur at solid-liquid interfaces to evaluate parameters that may modulate the optimization of battery efficiency. Utilizing electrochemical techniques, our objective is to deconvolute the mechanistic and rate-limiting factors associated with proton insertion from an acidic aqueous electrolyte into a thin film of tungsten trioxide (WO3). While WO3 has been investigated as a battery anode, the kinetics of cation insertion remain inadequately explored despite their effects on system efficiency. Through the Potentiostatic Intermittent Titration Technique (PITT), a developed application of chronoamperometry, along with Butler-Volmer equation fitting, our research endeavors to define the exchange current density and activation energy pertinent to cation insertion. The broader implications of exploring interfacial ion transfer phenomena manifest in advancing the fundamental understanding of energy storage processes.