CuCl Films Research Articles

Bio-based cellulose supported copper oxide nanoparticles for the reduction of nitro-aromatic compounds

Natural fibrous cellulose was extracted from sugarcane bagasse, the major solid waste produced in the sugarcane industry. Extracted cellulose fibers were loaded with Cu2O nanoparticles by adsorbing Cu2+ ions on the surface of fibers and followed by wet chemical reduction using sodium borohydride. Cu2O nanoparticles loaded cellulose fibers were made into a film (CuCL film) structure. The CuCL film was characterized by different techniques such as XRD, FTIR, SEM, EDS, XPS, and BET. The catalytic efficiency of CuCL film was evaluated with nitrophenol reduction reaction. CuCL film exhibited 97 % catalytic efficiency for 4-nitrophenol and good reusability up to 4th cycle. CuCL film also reduced 2, 4-dinitrophenol and 2, 4, 6-trinitrophenol with 91 % and 87 % efficiency.

An Advanced Model for Long-Term Localized Corrosion of Copper

The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of the Adaptive Phased Management (APM) plan, the federally-approved plan for the safe long-term management of Canada’s used nuclear fuel.1 Under the APM plan, used nuclear fuel will ultimately be placed within a deep geological repository (DGR) in a suitable host rock formation. Part of evaluating the long-term performance and safety of the repository system is understanding the behavior of the copper-coated container with respect to localized corrosion. Even though localized corrosion is not expected in the DGR design system, there is still a need to develop a mathematical model for localized corrosion of copper.A 2-D axisymmetric time-dependent model for the localized corrosion of copper was developed using the concept of an Evans droplet.2 The model accounts for three reversible electrochemical reactions on the metal surface (copper dissolution/plating, cuprous ion oxidation (Cu+) /cupric ion (Cu2+) reduction, and hydrogen (H2) evolution/oxidation) and three irreversible electrochemical reactions (cupric ion reduction, oxygen (O2) reduction, and hydroperoxyl ion (HO2 -) reduction). Dissolved cuprous ion reacts in a second chemical step to form the cuprous chloride (CuCl) salt film treated as a diffusion barrier, or it reacts to form the cuprous oxide (Cu2O) film that partially blocked the active area on the metal surface. The model also accounts for fifteen homogeneous reactions involving copper chloride complex, copper hydroxide complex, copper carbonate complex, and superoxide species. The associated equilibrium constants were obtained from PHREEQC thermodynamic software.3 The mathematical model was developed using the finite-element method (COMSOL Multiphysics). The model includes coupled, nonlinear, diffusion equations for ionic species, which include the contribution of migration, local electroneutrality, and homogeneous reactions. The anodic and cathodic regions are not predefined but, instead, are determined by values of local concentration and potential from the simulation results. The growth of nm-scale films was calculated implicitly without using finite-element meshing and surface coverage was expressed in terms of the thickness in units of monolayers. The model also accounted for the effect of porous CuCl film thickness on the surface oxygen concentration and potential applied on electrochemical reactions. The influence of temperature was included on model parameters such as equilibrium rate constant, diffusion coefficient, Henry’s law constant, solubility product constant and kinetic parameters associated with electrochemical reactions. Transient droplet temperature was described by interpolating results from a one-million-year simulation for the temperature change on the used fuel container surface.4 A total of 28 dependent spatial-temporal variables including species’ concentrations, potentials and local corrosion rate were solved in this model.In the current version of model, two extreme conditions were chosen such that droplet boundary has a faster or slower rate of oxygen decay for an initially air-saturated droplet. The model shows a 10-year time-dependent radial distribution of anodic and cathodic current density, surface coverage of CuCl film and Cu2O film, and localized corrosion rates and depths. It also shows a distribution of pH, potential, and concentrations of dissolved gaseous and ionic species through the entire droplet. Temperature and oxygen concentration is shown to have a strong contribution to the simulation results. Simulations show that the depth of corrosion is almost uniform over the elapsed time simulated and the maximum deviation from the average corrosion depth was less than 0.0004% for slower oxygen decay and less than 0.002% for faster oxygen decay in 10 years.References NWMO, “Choosing a Way Forward. The Future Management of Canada’s Used Nuclear Fuel. Final Study,” Nuclear Waste Management Organization, Toronto, Ontario, 2005.R. Evans, The Corrosion of Metals, E. Arnold & Company, London, 1926.PHREEQC Version 3, United States Geological Survey, 202, https://www.usgs.gov/software/phreeqc-version-3Guo, “Thermal response of a Canadian conceptual deep geological repository in crystalline rock and a method to correct the influence of the near-field adiabatic boundary condition”, Engineering Geology, 218 (2017), p50-p62. AcknowledgementThis work was supported by the Nuclear Waste Management Organization, Canada, under project 2000904.

The Electrochemical Deposition of Pd and Cucl Films on Graphene

Surface limited redox replacement (SLRR) is an electrochemical technique for depositing metal films monolayers in thickness, typically on other metals. As interest in graphene as a highly conductive, chemically resistant support for metal nanoparticles has risen, some have sought to apply this deposition technique to graphene as an electrochemical alternative to other chemical or vacuum-based deposition techniques. To better understand the nature of the interactions between the metal and graphene, our group has used this technique to deposit Pt on graphene to observe the structure of Pt and its epitaxy with the substrate. We have previously found that Pt prefers to bind to the bridge sites of graphene, preferring to form a simple-cubic-like structure and producing a slight lattice compression. We sought to expand on this study by observing the interactions of Pd with graphene. Pd was deposited on graphene using Cu-mediated SLRR, however, most Cu-mediated SLRR is performed with CuSO4 or Cu(ClO4)2 dissolved in H2SO4 or HClO4. This does not necessarily produce a strong Cu underpotential deposition feature on graphene, so HCl was used as the electrolyte instead. This produced a substantially more pronounced underpotential deposition feature, but cyclic voltammograms in this solution do not appear to agree with typical Cu-S-Cl Pourbaix diagram. This also resulted in two different types of structures, primarily Cu-containing films and primarily Pd-containing nanoparticles. The films were always found in the presence of the particles, but the particles did not always have accompanying films. A structural analysis of the particles determined that they preferred to interface with graphene along the (110) planes of Pd and have a slight elongation along the [001] direction of about 1.6% when oriented such that their columns were visible in the scanning transmission electron microscope. Based on an analysis of their orientation, this alignment and elongation appear to be the result of Pd minimizing its interfacial strain with graphene. A structural and compositional analysis of the films determined them to be CuCl, and they prefer to interface with graphene along their (111) plane, although the reason for this particular orientation is unclear as there is weaker evidence for a correlation between the alignment of the graphene and the films.

(Digital Presentation) A Mathematical Model for Localized Corrosion of Copper Under a Droplet

The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management (APM), the federally-approved plan for the safe long-term management of Canada’s used nuclear fuel.1 Under APM, used nuclear fuel will ultimately be placed within a deep geological repository (DGR) in a suitable host rock formation. Part of evaluating the long-term performance and safety of the repository system is understanding the behavior of the copper coated container with respect to localized corrosion. Even though localized corrosion is not expected in the DGR design system, there is still a need to develop a mathematical model for localized corrosion of copper.The presentation will describe the development of a 2-D axisymmetric time-dependent model for the localized corrosion of copper under a drop of electrolyte using the concept of an Evans droplet.2 The model accounts for two reversible electrochemical reactions on the metal surface (copper dissolution/plating and hydrogen (H2) evolution/reduction) and two irreversible electrochemical reactions (cupric ion (Cu2+) reduction and oxygen (O2) reduction). Dissolved cuprous ion (Cu+) reacts in a second chemical step to form the cuprous chloride (CuCl) salt film treated as a diffusion barrier, or it reacts to form the cuprous oxide (Cu2O) film that partially blocks the active area on the metal surface. The model also accounts for a series of homogeneous reactions involving copper chloride complex, copper hydroxide complex, copper carbonate complex, and superoxide species. The associated equilibrium constants were obtained from PHREEQC thermodynamic software.3 The model includes a total of 23 dependent spatial-temporal variables.The mathematical model is developed using the finite-element method (COMSOL Multiphysics). The model includes coupled nonlinear conservation equations for ionic species, which include the contribution of diffusion, migration, local electroneutrality, and homogeneous reactions. The anodic and cathodic regions are not predefined but are rather determined by values of local concentration and potential from the simulation results. The surface coverage of film was calculated implicitly and expressed in terms of the thickness in units of monolayers. The model also accounted for the effect of porous CuCl film thickness on the surface oxygen concentration and potential applied on electrochemical reactions.In this preliminary study, two extreme conditions were chosen such that the droplet boundary could either have an infinite supply of oxygen or it could have no external supply of oxygen for an initially air-saturated droplet. The results show a 3-year time-dependent radial distribution of anodic and cathodic current density, surface coverage of CuCl film and Cu2O film, and localized corrosion rates and depths. The results include a distribution of pH, potential, and concentrations of dissolved gaseous and ionic species through the entire droplet. The potential change as the system transitions from aerobic to anaerobic conditions matches the expected equilibrium potential difference.4 The model could be used to explore the influence of different parameters on the localized corrosion rate and depth, film thickness and growth, and each individual current profiles. The parameters may be adjusted to conform to the DGR environment.References NWMO, “Choosing a Way Forward. The Future Management of Canada’s Used Nuclear Fuel. Final Study,” Nuclear Waste Management Organization, Toronto, Ontario, 2005.R. Evans, The Corrosion of Metals, E. Arnold & Company, London, 1926.PHREEQC Version 3, United States Geological Survey, 202, https://www.usgs.gov/software/phreeqc-version-3Cleveland, M. E. Orazem, and S. Moghaddam, “Response to “Comment on “Nanometer-scale corrosion of copper in de-aerated deionized water” [J. Electrochem. Soc., 161, C107 (2014)],” Journal of the Electrochemical Society, 163 (2016), Y5-Y11. AcknowledgementThis work was supported by the Nuclear Waste Management Organization, Canada, under project 2000904.

Linking the Cu(II/I) and the Ni(IV/II) Potentials to Subsequent Passive Film Breakdown for a Cu−Ni Alloy in Aqueous 0.5 M NaCl

AbstractCopper and copper–nickel alloys are known to form partially passive films in marine conditions, both naturally and under positive potential bias. Here, the anodic passivation behaviour of copper and of constantan (Cu54Ni45Mn1) as a model for a copper‐nickel alloy are investigated and compared at high positive overpotentials and in 0.5 M NaCl(aq). Abrupt potential‐dependent passive film breakdown is observed for both Cu and Cu−Ni alloys during voltammetry and during chronoamperometry experiments. For Cu, a single transitions occurs at 0.2 V vs. SCE consistent with a Cu(II/I) process, leading to interfacial stress and breaking of a passive CuCl film. For Cu−Ni alloy, two stages are observed at 0.3 V vs. SCE due to a Cu(II/I) process and at 1.7 V vs. SCE due to a sub‐interfacial Ni(IV/II) process. A breakdown mechanism is proposed based on redox processes at the buried interface at the metallic conductor | passive ion conductor junction.

Electrochemical corrosion kinetics of cold spray copper composite coatings in a high potential region

AbstractIn this paper, copper composite anticorrosion and antifouling coatings were prepared by a cold spray technique. Polarization experiments of the coatings were performed by rotating ring‐disk electrode technology at high potential. The electrochemical reaction mechanisms were proposed, and corresponding polarization kinetics models were built. Experimental results show that the copper and cuprous oxide formed corrosion microcells in the coatings, and the cuprous oxide did not alter the electrochemical reaction process of copper. In the high potential region (about 0.2–0.8 V), a CuCl film formed on the surface of the coatings was not damaged or broken down. The film played a role in corrosion protection. The currents in the high potential region increased relative to the limiting current 1. Because in the high potential region, was produced by the dissolution of the CuCl film and was oxidized to Cu2+. In addition to being oxidized to Cu2+, has the other two destinations, which were deposition as a CuCl film and diffusion to the solution bulk. The three processes were in parallel competition relations. In the limiting current 2 region, oxidation of was dominant. A rate‐controlling step of electrochemical dissolution of the coatings in the high potential region was the diffusion processes of and Cu2+. The electrochemical polarization kinetic models based on the reaction mechanisms established in this research accorded well to the experimental results. It demonstrated the rationality of polarization kinetics models and reaction mechanisms.

Anodic Dissolution of Copper in Choline Chloride-Urea Deep Eutectic Solvent

The anodic dissolution behavior of copper in choline chloride-urea deep eutectic solvent (ChCl-urea DES) was investigated using coulometric weight loss experiments, polarization techniques, electrochemical impedance spectroscopy and UV–Vis spectroscopy. It is indicated that the copper was mainly oxidized copper(I) ion, and formed Cu(I) complex, [CuCl2]− and [CuCl3]2−, in electrolyte. The copper was found to be easier dissolved when the ChCl-urea electrolytes contained 0.01 M CuCl. A higher CuCl concentration led to increase of polarization resistance, and further caused the slight decrease of corrosion current density. The apparent activation energy of the dissolution process was 19.1 kJ·mol−1 assigning a mass transport limited reaction. The impedance measurements and impedance data fitting to equivalent circuits show that the dissolution of copper in ChCl-urea DES can be described by the duplex salt film model, consisting of compact CuCl and saturated Cu(I) complex film. The formation of duplex salt film can be decreased by increasing the temperature, thereby increasing ligand and Cu(I) transport.

Nucleation and growth of CuCl thin films on commercially available SnO2/glass substrates by the sublimation method

Studies on cuprous chloride (CuCl) sublimation, thin film deposition, and growth on commercially available tin oxide coated glass substrates were performed by adjusting substrate and vapor source thermal parameters. A systematic method for measuring CuCl film thicknesses was implemented using scanning white light interferometry. Furthermore, structural characteristics of the films were evaluated via scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Thickness measurements at established locations determined the growth rates of CuCl thin films with respect to deposition conditions. SEM and EDS results revealed that localized clusters (islanding) occurred at the initial stages of growth. As growth continued, the islands began to coalesce and develop nonuniform CuCl grain networks across the substrate. The results support the Volmer–Weber growth mode as the primary mechanism responsible for such growth behavior.

Enhanced Friction-Reducing Behavior of Stearic Acid Film on the Etched Copper

A simple two-step process was developed to render the low-friction copper surface with longer durability. The copper substrate was firstly etched by immersing it in H2O2/HCl solution to fabricate a CuCl film, while a layer of stearic acid was then deposited on the CuCl film. Scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared microscopy and water contact angle measurements were used to analyze the morphological features, the chemical composition and hydrophobicity of freshly prepared specimens, respectively. Moreover, the friction-reducing behavior of the dual-modified copper surface sliding against a steel ball under unlubricating condition was evaluated in tribotester with a ball-on-plate configuration. It is found that the tribological performances of copper substrate are much improved by depositing stearic acid films on the etched copper.

Fabrication of cuprous chloride films on copper substrate by chemical bath deposition

Polycrystalline CuCl films were fabricated by chemical bath deposition (CBD) on a Cu substrate at a low solution temperature of 90°C.Continuous CuCl films were prepared using the copper (II) chloride (CuCl2) compound as the precursor for both the Cu2+ and Cl− sources, together with repeated HCl dip treatments. An HCl dip pretreatment of the substrate favored the nucleation of CuCl crystallites. Further, interrupting the film deposition and including an HCl dip treatment of the film growth surface facilitated the deposition of a full-coverage CuCl film.A dual beam (FIB/SEM) system with energy dispersive spectrometry facilities attached revealed a homogeneous CuCl layer with a flat-top surface and an average thickness of about 1μm. Both the excitonic and biexcitonic emission lines were well-resolved in the 6.4K photoluminescence spectra. In particular, the free exciton emission line was observable at room temperature, indicating the good quality of the CuCl films prepared by CBD.

Exceptional Transparency Window in a Finite Alternating Stack of Ag and CuCl Films

I show that the transmission coefficient of light propagating normally to the face of a stack of thin alternating films of silver and CuCl may exhibit a narrow exceptional transparency window at a frequency slightly lower than the excitonic resonance frequency. This window is caused by the coupling of the plasmon mode of the metal with the excitonic mode of the semiconductor and is principally due in the present system to the strong oscillator strength and the narrow width of the CuCl excitonic mode.

Anomalous Photoluminescence of Weakly Confined Excitons including Radiative Correction in Nano-to-Bulk Crossover Regime

We develop a theoretical formalism to calculate photoluminescence (PL) spectrum of weakly confined excitons incorporating the microscopic nonlocal optical response. The nonlocality is caused by the center-of-mass (c. m.) motion of exciton and becomes remarkable in nano-to-bulk crossover regime. The theory successfully explains the characteristics of recently observed peculiar PL spectra in high quality CuCl films [5], wherein the signals appear at the exciton states with the very large radiative corrections not only for the lowest level but also for the higher ones including non-dipole types of excitons.

Temperature dependent photoluminescence of nanocrystalline γ-CuCl hybrid films

Organic–inorganic hybrid films combine the basic properties of organic and inorganic materials and offer special advantages that enhance optical, thermal and mechanical properties. We have studied the temperature dependent photoluminescence (PL) of nanocrystalline γ-CuCl hybrid films from 15K to room temperature in order to investigate the electronic transitions of the hybrid films. The I1 impurity bound exciton peak is the most intense emission peak at 15K but the peak intensity decreases rapidly with increasing temperature due to the low binding energy of this exciton bound to an impurity center and above 80K all three excitonic and biexcitonic peaks, except the Z3 free exciton emission peak disappeared. The biexciton emission peak intensity follows a quadratic dependency on power in the excitation power range <10 kWcm−2. The integrated Z3 excitonic PL intensity is almost independent of the temperature below 80K, while above 100K the PL emission intensity decreases rapidly. Thermal quenching of the Z3 free exciton PL emission in hybrid films has been observed. The full width at half maximum (FWHM) of the free exciton peak was investigated as a function of temperature and was explained by a theoretical model which considers the scattering of excitons with acoustic phonons and longitudinal optical phonons. The FWHM of the Z3 free exciton emission peak increases with increasing temperature, and a value of ~76meV was deduced for the FWHM at room temperature, which is comparatively better than ZnO (106meV) and GaN (100meV) nanostructures. The Z3 free exciton energy of the hybrid films exhibits a blue shift of 3meV at 15K compared to the bulk CuCl samples which may be due to a dead layer effect near the CuCl nanocrystal surface. The exciton energy also presents a blue shift of ~41meV with increasing temperature from 15K to room temperature. The results obtained for the γ-CuCl hybrid films are comparable to those of vacuum evaporated and sputtered CuCl films reported in the literature.

Soft x-ray spectroscopic investigation of Zn doped CuCl produced by pulsed dc magnetron sputtering

We report on a systematic investigation of the electronic properties of UV-light emitting Zn doped CuCl thin films implemented using near edge x-ray absorption fine structures (NEXAFS) and high-resolution x-ray photoemission spectroscopy. A clear shift of the valence band maximum towards higher binding energy by 0.2 ± 0.1 eV was observed in Zn doped CuCl as compared to undoped CuCl. This shift is in correlation with the increase in conductivity measured by the Hall effect measurements. A decrease in the optical band gap of CuCl film is also observed as a function of Zn doping. The profound changes in the full width at half maximum and the gradual disappearance of satellite features of Cu 2p core level photoemission as a function of Zn dopant are attributed to the reduced presence of the surface layer of Cu2+ species with d9 configuration in the doped films. These investigations help us to understand the doping mechanisms and underlying physics. The reduced presence of the Cu2+ related surface layer as a function of Zn doping is also verified using NEXAFS.

Evaluation of conduction mechanism and electronic parameters for Au/organic–inorganic CuCl hybrid film/ITO structures

Hybrid materials are capable of combing organic and inorganic compounds into a nano-composite with unique characteristics. An example of such organic–inorganic CuCl hybrid films is studied here using a combination of organic polysilsesquioxane and inorganic CuCl; γ-CuCl is an ionic I–VII compound semiconductor material with the zincblende structure at room temperature. It has excellent ultraviolet (UV) emission properties at room temperature and is a promising candidate material for optoelectronic applications. The CuCl hybrid films were deposited on indium tin oxide (ITO)-coated glass by simple spin-coating techniques. Au/CuCl hybrid film/ITO structures were fabricated, and field-dependent electrical studies were carried out at room temperature in the range 2.5 × 105–3.5 × 106 V m−1. We confirm that the organic–inorganic CuCl film structure behaves as an effective single semiconducting medium, possessing bandstructure and other related properties. For electric field magnitudes up to 1.25 × 106 V m−1, an ohmic conduction mechanism was observed, and for field magnitudes >1.5 × 106 V m−1, Schottky emission conduction prevails in these structures. The electronic parameters were evaluated and an effective barrier height, ideality factor and series resistance were found to be 0.84 ± 0.05 eV, 1.12 ± 0.08 and 50 ± 2 MΩ, respectively, whereas the effective barrier height obtained from the C–V measurement was 1.05 ± 0.05 eV. This value is somewhat higher than the value obtained from the I–V measurement. This difference is likely caused by the presence of a thin intervening insulating layer between the hybrid film surface and the Schottky metal. The density distribution of the interface states decreases with an increase of the energy of the interface states. This organic–inorganic CuCl hybrid film behaves as an effective single semiconductor material structure, and a schematic energy-level diagram for the device is proposed.

Generation of entangled-photon pairs from biexcitons in CuCl thin films: Nano-to-bulk crossover regime

We have constructed a theoretical framework of the biexciton-resonant hyperparametric scattering for the pursuit of high-power and high-quality generation of entangled photon pairs. Our framework is applicable to nano-to-bulk crossover regime where the center-of-mass motion of excitons and biexcitons is confined. Material surroundings and the polarization correlation of generated photons can be considered. We have analyzed the entangled-photon generation from CuCl film, by which ultraviolet entangled-photon pairs are generated, and from dielectric microcavity embedding a CuCl layer. We have revealed that in the nano-to-bulk crossover regime we generally get a high performance from the viewpoint of statistical accuracy, and the generation efficiency can be enhanced by the optical cavity with maintaining the high performance. The nano-to-bulk crossover regime has a variety of degrees of freedom to tune the entangled-photon generation, and the scattering spectra explicitly reflect quantized exciton-photon coupled modes in the finite structure.

ChemInform Abstract: Dramatic Improvement of Excitonic Photoluminescence in Metal Halide Films

AbstractReview: 105 refs.

Synthesis and Characterization of Copper (I) Chloride (CuCl) Nanocrystals in Conductive Polymer for UV Light Emitters

AbstractIntrinsic γ-Copper (I) Chloride is an ionic I-VII compound semiconductor material with relatively low conductivity. To fabricate an efficient electroluminescent device based on CuCl nanocrystals (NC) the conductivity of the CuCl NC film should be relatively high. In order to improve the conductivity of CuCl films, nanocrystals were embedded in a highly conductive polymer (Polyaniline) and deposited on glass substrates via the spin-coating method. The deposited films were heated at 140°C for durations between 1 and 12 hours in vacuo. The room temperature UV-Vis absorption spectra for all CuCl films showed both Z1,2 and Z3 excitonic absorption features and the absorption intensity increased as the anneal time increased. Room temperature photoluminescence (PL) measurements of the hybrid films reveal very intense Z3 excitonic emission. Room temperature X-ray diffraction (XRD) confirmed the preferential growth of CuCl nanocrystals whose average size is ≈40 nm in the &lt;111&gt; orientation. Resistivity measurements were carried out using a four-point probe system, which confirmed that the resistivity of the composite film was ≈500 Ω/cm. This is an improvement when compared to the vacuum evaporated CuCl thin films.

Zn Doped Nanocrystalline CuCl Thin Films for Optoelectronic Applications

AbstractWe report on the use of Zn as an n-type dopant in CuCl thin films for optoelectronic applications, wherein maximum n-type doping of the order of 1018 cm -3 has been achieved. Zn doped nanocrystalline CuCl thin films are successfully deposited on glass and Si substrates by pulsed dc magnetron sputtering. Structural and morphological properties are investigated using X-ray diffraction (XRD) studies and Scanning Electron Microscopy (SEM), respectively. The conductivity of the CuCl:Zn films is examined using the four point probe technique. An order of magnitude increase in the conductivity of CuCl, by the doping with Zn is reported herein. The doped CuCl films display strong room temperature cathodoluminescence (CL) at λ˜ 385nm, which is similar to that of the undoped films. Hall Effect measurements show an n-type conductivity of the doped films.

Nanosized WO 3 thin film as a multifunctional hydrogen material for achieving photolysis in CuCl films via hydrogen photosensitization

The paper highlights less-common properties of nanosized WO 3 thin films which make it possible to achieve photolysis in CuCl films via the use of a CuCl–WO 3 double-layer structure. The WO 3 film provides first photoinduced detachment of hydrogen atoms from organic molecules adsorbed on the oxide surface; the hydrogen atoms, being transferred into WO 3, turn into electrons and protons which migrate then to the CuCl film forming sensitizing centres on the halide surface being illuminated simultaneously with the illumination of the WO 3 surface. This in turn gives rise to photolysis in the CuCl films, which does not occur without the hydrogen sensitization. The nanosized WO 3 film makes it possible to trigger two famous surface photochemical reactions, first proton-coupled electron transfer between the hydrogen-donor molecules and the oxide surface, and then the photolysis of the halide, which radically changes the optical parameters of both the WO 3 and the CuCl films.