Higher Photocurrent Density Research Articles

Single-atomic ruthenium coupling with NiFe layered double hydroxide in-situ growth on BiVO4 photoanode for boosting photoelectrochemical water splitting

In the present work, NiFe layered double hydroxide (LDH) supported single Ru atoms in-situ growth on BiVO4 photoanode (BiVO4@NiFe-LDHs/Ru) was fabricated to enhance the photoelectrochemical (PEC) water splitting. Ru atoms anchored to NiFe-LDHs via oxygen coordination to form Ru-O-M bonds, which induced electrons rearrangement to improve charge carriers separation and injection. Combining with the synergistic effect of Ru and NiFe-LDHs, BiVO4@NiFe-LDHs/Ru achieves high photocurrent density of 4.65 mA/cm2 at 1.23 V vs. RHE. Besides, Ru atoms induced formation of V(5−x)+ to stabilize V atoms in the lattice of BiVO4, which avoided V5+ dissolution during PEC water oxidation process. Density functional theory (DFT) calculation indicates that Ru SAs anchored to BiVO4@NiFe-LDHs decrease the reaction energy barrier of rate-limiting step (*O → *OOH), resulting in acceleration of OER process. This work provides an effective pathway to design high efficient and stable photoanodes with single atoms for feasible PEC water splitting application.

Barium titanate perovskite nanoparticles integrated reduced graphene oxide nanocomposite photoanode for high performance dye-sensitized solar cell

Nanocomposites comprised of barium titanate perovskite nanoparticles decorated reduced graphene oxide (BaTiO3-RGO NC) were formed through facile hydrothermal method. X-ray diffractometer profile confirmed crystallite and tetragonal phase of BaTiO3. Identification of D and G bands in Raman investigation and XPS spectra disclosed existence of graphene in the prepared BaTiO3-RGO NC. FE-SEM examination indicates small sized BaTiO3 NPs are obviously decorated on the graphene sheets by strong binding forces between graphene and BaTiO3 NPs. Among graphene of different wt%, BaTiO3-RGO NC with 1.5 wt% showed lowest PL intensity, indicating effective reduction of photogenerated charge carrier recombination. Dye-sensitized solar cell fabricated using BaTiO3-RGO NC photoanode having 1.5 wt% graphene displays high efficiency of 4.93% associated with high photocurrent density.

An insight into a novel calixarene-sensitized Calix@Nb2CTx/g-C3N4 MXene-based photocatalytic heterostructure: Fabrication, physicochemical, optoelectronic, and photoelectrochemical properties

The development of highly efficient and cost-effective multifunctional photocatalysts is of current global interest because these photocatalysts have the potential to address the energy and water crisis. Herein, an efficient calixarene-based [email protected]2CTx/g-C3N4 (Cx-Nb-CN) photocatalyst was prepared through the formation of covalent bonds between the calixarene (Cx-COCl), g-C3N4 (CN), and Nb2CTx MXene. Enhanced optoelectronic and photoelectrochemical (PEC) properties were observed upon introducing Cx-COCl calixarene and Nb2CTx complexes to the g-C3N4 (CN) photocatalyst. The XPS valence band measurements demonstrated the narrowing of the energy band gap for the composites due to the downshifting and upshifting of the CB and VB, correspondingly. Due to the sensitization effect, the Cx-CN presented superior photocatalytic properties relative to the pristine CN. Moreover, reduced charge transfer resistance (Rct = 110.7 Ω.cm2) and the highest photocurrent density (Jp = 7.95 mA/cm2) were observed for the Cx-Nb-CN-5 heterostructure. The Schottky-heterostructures Cx-Nb-CN-1, Cx-Nb-CN-3, and Cx-Nb-CN-5 presented high linear sweep current densities (JLSV) of 8.61, 12.39, 14.04 mA/cm2 signifying excellent light utilization and efficient separation of charge carriers, respectively. The fabricated photocatalyst exhibits excellent physicochemical and photocatalytic properties with the potential to facilitate host-guest complexation towards environmental detoxification and energy conversions.

(Keynote) Recent Insights on Carrier Generation, Transport, and Extraction in Metal Oxide Photoelectrodes

After the absorption of light, the next steps in any artificial photosynthetic system are the generation, transport, and extraction of photoexcited charge carriers. These steps are well understood in solid state systems based on traditional semiconductors, such as Si and III-V absorbers, resulting in quantum efficiencies close to one for optimized devices. For metal oxide-based absorbers, which have attracted much interest in the past decades because of their relatively good (photo)chemical stability and low cost, the reported efficiencies tend to be much lower. This is often attributed to recombination at defects. While these may indeed adversely affect the efficiency, there are several other fundamental loss mechanisms in metal oxides that are not always fully appreciated. For example, certain metal ions exhibit localized d-d transitions that do not result in mobile charge carriers, resulting in a photogeneration yield < 1. Recent work showed that it is possible to quantify the fraction of mobile photoexcited carriers, from which an upper limit of the achievable photocurrent can be derived [1]. Losses can also occur in the form of recombination or carrier localization during transport. The chance of reaching the interface is often expressed as the carrier diffusion length, which in turn depends on the carrier lifetime and its mobility. Convenient contact-free methods to determine these parameters are time-resolved microwave conductivity (TRMC) and time-resolved THz spectroscopy (TRTS) [2]. Here, one of the challenges is to determine whether the decay in photoconductivity is due to a decay in carrier concentration (i.e., recombination), carrier mobility (trapping, polaron formation), or both. We recently developed a general analysis method for determining the diffusion length which is valid for time-dependent mobilities as well as time-dependent lifetimes [3]. Intringuingly, this method revealed a carrier diffusion length of only 15 nm for BiVO4, which is significantly shorter than previously reported values by us and others. The only way this short diffusion length can be reconciled with the high photocurrent densities reported for this material is by assuming field-assisted charge separation. The role of the electric field is, however, poorly understood in the photoelectrochemistry and photocatalysis communities [4]. In a system without externally applied bias, the electric field does not separate the charges; instead, charge separation is driven by the presence of selective contacts. During my presentation I will review these concepts and discuss how a better understanding of loss mechanisms, the role of the electric field, and selective contacts may help us design more efficient metal oxide-based photoelectrodes.

CoFe Amorphous Double Hydroxides Modified Hematite Photoanode with the Synergism of Co and Fe for Enhanced Photoelectrochemical Water Oxidation

In this study, a hematite photoanode with a CoFe-ADH co-catalyst loaded on the surface was successfully prepared through hydrothermal treatment, annealing, and electrodeposition. We investigated the influence of the deposition time and Co/Fe molar ratio for CoFe-ADH on the performance of α-Fe2O3 in photoelectrochemical (PEC) water oxidation. With an optimized condition of CoFe-ADH, the prepared CoFe-ADH/α-Fe2O3 photoanode exhibited a high photocurrent density of 1.58 mA/cm2 at 1.23 VRHE, which is about 2.5 times as high as that of α-Fe2O3. A series of characterization results and detailed mechanism studies reveal that surface modification of hematite by introducing CoFe-ADH can boost the surface charge transfer efficiency, which can be attributed to the good optical transparency, the amorphous structure of CoFe-ADH, and the synergism of Co and Fe in CoFe-ADH. The good optical transparency contributes to decreasing the loss of light absorption by the photoanodes; the amorphous structure could prevent the formation of grain boundaries and provide more active catalytic sites for PEC water oxidation; and the synergism of Co and Fe in CoFe-ADH enhances photogenerated carriers effective separation and the hole’s injection. This work provides valuable insights into the influence of bimetallic co-catalysts on the PEC performance of photoanodes, offering guidance for photoanodes to achieve excellent performance.

A novel α-Fe2O3 photoanode with multilayered In2O3/Co–Mn nanostructure for efficient photoelectrochemical water splitting

Hematite (α-Fe2O3) is considered one of the most promising materials for PEC water splitting under solar light. However, the drawbacks of lower charge transfer efficiency and slow oxygen evolution reaction (OER) kinetics seriously limited the practical application of α-Fe2O3 photoanodes. In this work, a multilayer structure modified α-Fe2O3 photoanode is proposed. Firstly, the In2O3 nanolayers were loaded onto the surface of α-Fe2O3 nanorods, significantly increasing the photoelectrochemical (PEC) water oxidation activity. The heterojunction form by the In2O3 passivation layer with α-Fe2O3 effectively promotes charge separation. Next, an electrodeposition method deposited a nanosheet combining ultrathin non-crystalline Co(OH)x and Mn3O4 nanocrystals (Co–Mn) on the α-Fe2O3 thin film. As an efficient co-catalyst, the Co–Mn nanosheets assisted the performance of α-Fe2O3 PEC water oxidation. The optimized α-Fe2O3–In2O3–Co(OH)x-Mn3O4 photoanode produces a high photocurrent density of 6.5 mA/cm2 at 1.23 V (vs. RHE), a maximum IPCE of 57.9% at 400 nm can reach.

Photocatalytic activity of B-doped nano graphene oxide over hydrogenated NiO-loaded TiO2 nanotubes

A hydrogenated NiO-loaded anatase TiO2 with unique heterostructure nanotube arrays (denoted as H:(NiO/TiO2)) NTs were synthesized, followed by the attachment of boron-doped reduced nanographene oxide nanoparticles (B-nGO NPs) to form a vigorous composite photoelectrode B-nGO/H:(NiO/TiO2) NTs. The p-n junction created between p-type NiO and n-type TiO2 produces sufficient built-in electric field to facilitate the electron–hole pair separation and boost the interfacial electron transfer, subsequently a hydrogenation treatment to adjust the donor density and maximize the electron–hole separation. The microstructure characterization with synchrotron-based X-ray techniques straightened out that the created NiO oxygen vacancies can provide emptier d-orbitals to accept more photoexcited electrons. With the incorporation of B-nGO NPs, the partially replacement of C atoms of nGO by B atoms can form an electron–hole-rich configuration in the heterostructure to decrease the Fermi level, with a more rapid electron transfer toward TiO2 substrate during photocatalysis, which also confirmed by quantum-chemical calculations. The as-synthesized B-nGO/H:(NiO/TiO2) NTs exhibited a high photocurrent density (2.0 mA/cm2) and an effective photoconversion efficiency (2.07%) under simulated sunlight irradiation (AM1.5G, 100 mW/cm2). The eventuated photoconversion efficiency is 6 times enhanced with respect to the pristine TiO2, along with an impressive hydrogen evolution rate of 31 μmol/h/cm2. Moreover, the photocurrent durability test has confirmed the stability of B-nGO/H:(NiO/TiO2) electrode, with only a slight decay of <1% after continuous illumination for more than 4 h. Incident photon conversion efficiency spectra have revealed a boosted photo-response under visible light region (extended to ∼520 nm) with the synergistic attachment of NiO and B-nGO.

Introducing Bidirectional Axial Coordination into BiVO4@Metal Phthalocyanine Core-Shell Photoanodes for Efficient Water Oxidation.

Core-shell photoanodes have shown great potential for photoelectrochemical (PEC) water oxidation. However, the construction of a high-quality interface between the core and shell, as well as a highly catalytic surface, remains a challenge. Herein, guided by computation, we present a BiVO4 photoanode coated with ZnCoFe polyphthalocyanine using pyrazine as a coordination agent. The bidirectional axial coordination of pyrazine plays a dual role by facilitating intimate interfacial contact between BiVO4 and ZnCoFe polyphthalocyanine, as well as regulating the electron density and spin configuration of metal sites in ZnCoFe phthalocyanine, thereby promoting the potential-limiting step of *OOH desorption. The resulting photoanode displayed a high photocurrent density of 5.7±0.1 mA cm-2 at 1.23 VRHE. This study introduces a new approach for constructing core-shell photoanodes, and uncovers the key role of pyrazine axial coordination in modulating the catalytic activity of metal phthalocyanine.

Introducing Bidirectional Axial Coordination into BiVO4@Metal Phthalocyanine Core–Shell Photoanodes for Efficient Water Oxidation

AbstractCore‐shell photoanodes have shown great potential for photoelectrochemical (PEC) water oxidation. However, the construction of a high‐quality interface between the core and shell, as well as a highly catalytic surface, remains a challenge. Herein, guided by computation, we present a BiVO4 photoanode coated with ZnCoFe polyphthalocyanine using pyrazine as a coordination agent. The bidirectional axial coordination of pyrazine plays a dual role by facilitating intimate interfacial contact between BiVO4 and ZnCoFe polyphthalocyanine, as well as regulating the electron density and spin configuration of metal sites in ZnCoFe phthalocyanine, thereby promoting the potential‐limiting step of *OOH desorption. The resulting photoanode displayed a high photocurrent density of 5.7±0.1 mA cm−2 at 1.23 VRHE. This study introduces a new approach for constructing core–shell photoanodes, and uncovers the key role of pyrazine axial coordination in modulating the catalytic activity of metal phthalocyanine.

Rationally constructing intercrossed CuInS2 nanosheets on TiO2 nanorods for efficient photoelectrochemical water splitting

Photoelectrochemical (PEC) water splitting serves as an intriguing strategy for solar energy storage and conversion, but still suffers from the poor efficiency. In this work, a Z-scheme heterostructure comprised of CuInS2 nanosheets and TiO2 nanorods with an intercrossed structure was fabricated. Boosted by the well-matched structure, the as-prepared CuInS2/TiO2 hybrid achieved a high photo-electrocatalytic hydrogen evolution rate of 12.4 µmol/h, which was16 times greater than pure TiO2, owing to more effective solar energy utilization and interfacial photocarrier separation. Furthermore, PEC studies demonstrated that the novel hybrid offered a much higher photocurrent density than the nanoparticle counterpart, which could be ascribed to the elevated separation efficiencies of the photogenerated electron-hole pairs, and accompanied by efficient charge carrier transport. Based on the obtained results, this work provided a potential and promising approach for the fabrication of photo-electrocatalyst, which may inspire additional mechanism research of PEC and photo-electrocatalytic systems with hierarchical architecture.

Porous Zn1-xCdxSe/ZnO Nanorod Photoanode Fabricated from ZnO Building Blocks Grown on Zn Foil for Photoelectrochemical Solar Hydrogen Production.

Solar energy is the most promising, efficient, environmentally friendly energy source with the potential to meet global demand due to its non-polluting nature. Herein, a porous Zn1-xCdxSe/ZnO nanorod (NR) heterojunction was synthesized by hydrothermal and low-temperature solvothermal methods. First, the ZnO NR was grown on a Zinc foil, and an inorganic-organic hybrid ZnSe(en)0.5 material was developed by the low-temperature solvothermal method. In this work, the ZnO NR acted as a base material and a building block for the growth of ZnSe(en)0.5. Moreover, after the solvothermal process, the reduced Se2- reacts with the ZnO NR and forms inorganic-organic hybrid ZnSe(en)0.5. After the selenization process, the obtained material shows a red brick color due to the absorbance of excessive Se metal particles during the solvothermal process. Furthermore, in order to enhance the photoelectrochemical properties, the Cd2+ ion exchange method was applied at various temperatures (140, 160, and 180 °C for 3 h) to produce a precursor material to a porous Zn1-xCdxSe/ZnO NR nanostructure. The optimum Zn1-xCdxSe/ZnO NR-160 photoanode showed a high photocurrent density of 7.8 mA·cm-2 at -0.5 V vs. Ag/AgCl with a hydrogen evolution rate of 199 μmol·cm-2/3 h. The improved photocurrent performance was attributed to effective light absorption and prolonged recombination lifetime.

BiVO4 Photoanodes Modified with Synergetic Effects between Heterojunction Functionalized FeCoOx and Plasma Au Nanoparticles

The design and development of high-performance photoanodes are the key to efficient photoelectrochemical (PEC) water splitting. Based on the carrier transfer characteristics and localized surface plasmon resonance effect of noble metals, gold nanoparticles (AuNPs) have been used to improve the performance of photoanodes. In this study, a novel efficient composite BiVO4/Au/FeCoOx photoanode is constructed, and the quantitative analysis of its performance is systematically conducted. The results reveal that the co-modification of AuNPs and FeCoOx plays a synergetic role in enhancing the absorption of ultraviolet and visible light of BiVO4, which is mainly attributed to the localized surface plasmon resonance effect induced by AuNPs and the extended light absorption edge position induced by the BiVO4/FeCoOx heterojunction. The BiVO4/Au/FeCoOx photoanode exhibits a high photocurrent density of 4.11 mA cm−2 at 1.23 V versus RHE at room temperature under AM 1.5 G illumination, which corresponds to a 299% increase compared to a pristine BiVO4 photoanode. These results provide practical support for the design and preparation of PEC photoanodes decorated with AuNPs and FeCoOx.

Mn-doped ZnS nanoparticle photoanodes: Synthesis, structural, optical, and photoelectrochemical characteristics

In this work, Mn-doped zinc sulfide (Mn:ZnS) nanoparticles (NPs) have been synthesized as a promising material for photoelectrochemical water splitting (PEC), using the co-precipitation method. PEC properties of Mn-doped zinc sulfide NPs were considered under the correlation between Mn-doping level and their particle size. The highest photocurrent density (8.03 mA cm−2) and largest photoconversion efficiency (0.63%) (at 0.4 V vs. RHE) were reached at 6 mol% Mn. Based on the results of used various materials characterization techniques, including transmission electron microscopy (TEM), X-ray diffraction, photoluminescence spectrum, and absorbance spectrum, it can be assessed that the outstanding PEC characteristics of Mn:ZnS photoanode are attributed to the narrow bandgap of Mn:ZnS nanoparticles and their notably small particle size, which is originated from the Mn-doping. For application, the stability and the effect of various electrolytes were also investigated.

Optimization of Si photocathode formation conditions through correlation between saw damage removal and black Si

This study aimed to address the correlation between the saw damage removal (SDR) process and the formation of a nanoporous structure in order to fabricate a phototoelectrochemical (PEC) water splitting photocathode using silicon (Si) wafer utilized in solar cell. The experimental conditions were categorized into two groups: 1) before and after SDR process, and 2) the nanoporous structure formation time (ranging from 1 to 10 min) to identify the optimized conditions for enhancing efficiency. The results showed that the Si photocathode manufactured with a nanoporous structure fabricated for 5 min after SDR process had the lowest reflectance and interfacial defect, and the highest photocurrent density. This is because saw damage on the wafer caused many defects on the surface, making it difficult to form a uniform nano-porous structure. The SDR process helped in eliminating the saw damage and creating a uniform Si surface. In addition, the uniform nanoporous structure facilitated substantial light absorption, leading to the creation of numerous electrons and hole pairs, and resulted in achieved high efficiency by providing smoother the movement of carriers due to low interfacial defects. In summary, this study established a correlation between the SDR process and the formation of a nanoporous structure in the manufacturing of Si wafer for solar cells as a photocathode, and confirmed that the uniform nanostructure remarkably improves the photocurrent density characteristics.

Surface‐Passivated Vertically Oriented Sb2S3 Nanorods Photoanode Enabling Efficient Unbiased Solar Fuel Production

AbstractThe lack of highly efficient photoanodes presents a significant challenge to implementing the promising strategy of unbiased solar‐to‐fuel conversion. To achieve high‐performance photoanodes, improving their light harvesting and charge separation/injection capabilities is indispensable. Herein, solution‐processed vertically oriented Sb2S3 nanorod arrays on substrate are obtained via a Au seed layer, resulting in improved optoelectronic properties (due to the light scattering effect) and favorable crystallographic orientation of the 1D nanostructure. Moreover, the (NH4)2WS4 treatment caps the surface of the nanorods with an amorphous WSx layer and passivates the sulfur vacancy of Sb2S3, resulting in boosted charge extraction to the reactants. The resulting photoanode is employed to drive an iodide oxidation reaction (IOR), which is a prominent alternative to sluggish water oxidation reactions, exhibiting a high photocurrent density of 13 mA cm−2 at 0.6 V versus the reversible hydrogen electrode. Subsequently, an unassisted hydrogen generation device is demonstrated by combining an Sb2S3 nanorod array‐based photoanode for IOR and a perovskite‐based photocathode for the hydrogen evolution reaction, achieving an efficient hydrogen production current density of 5.7 mA cm−2 without any external bias.

Photochemical Diodes for Simultaneous Bias-Free Glycerol Valorization and Hydrogen Evolution.

Artificial photosynthesis offers a route to producing clean fuel energy. However, the large thermodynamic requirement for water splitting along with the corresponding sluggish kinetics for the oxygen evolution reaction (OER) limits its current practical application. Here, we offer an alternative approach by replacing the OER with the glycerol oxidation reaction (GOR) for value-added chemicals. By using a Si photoanode, a low GOR onset potential of -0.05 V vs RHE and a photocurrent density of 10 mA/cm2 at 0.5 V vs RHE can be reached. Coupled with a Si nanowire photocathode for the hydrogen evolution reaction (HER), the integrated system yields a high photocurrent density of 6 mA/cm2 with no applied bias under 1 sun illumination and can run for over 4 days under diurnal illumination. The demonstration of the GOR-HER integrated system provides a framework for designing bias-free photoelectrochemical devices at appreciable currents and establishes a facile approach to artificial photosynthesis.

WO3 layer sensitized with BiVO4 and MIL-101(Fe) as photoanode for photoelectrochemical water oxidation

Thick tungsten oxide layers were prepared electrophoretically in order to be used as photoanodes in photoelectrochemical water oxidation applications. The highest photocurrent density was obtained for a WO3 layer with thickness of ∼900 nm. Additionally, WO3/BiVO4 and WO3/BiVO4/MIL-101(Fe) heterojunctions have been fabricated using WO3 layer as substrate. WO3/BiVO4 shows an increased value of the electrochemical active surface area indicating that more sites of this photoanode are activated through the formation of the heterojunction. The small V5+ signals observed in the V 2p XPS spectra of these heterojunctions were attributed to the substitution of V5+ atoms with W6+ atoms on the surface of BiVO4. Excessive W doping of the BiVO4 film determined the decrease of the photoelectrochemical performance of WO3/BiVO4 photoanode. The significant improvement of the photoconversion efficiency of the sample decorated with MIL-101(Fe) indicated that this co-catalyst provides sites more efficiently in the photoelectrochemical process. This performance was correlated with the reduced value of the charge transfer resistance at electrode/electrolyte interface obtained from electrochemical impedance spectroscopy investigation.

Enhanced Photoelectrochemical Activity of CuWO4 Photoanode by Yttrium Doping

Yttrium-doped copper tungstate photoelectrodes are prepared by depositing an yttrium-doped CuWO4 film (Y-CuWO4) on conductive glass substrates by dip coating. The morphology and chemical composition confirm the fabrication of yttrium-doped CuWO4 films. The optical bandgap of the photoelectrodes is studied by UV–vis diffuse reflectance and a bandgap of 2.30 eV is obtained for the pure CuWO4 photoelectrode. The yttrium-doped photoelectrodes show a small shift of the bandgap to higher values, which according to DFT calculations can be ascribed to a higher density of electronic states in the first conduction band from incorporating yttrium into the structure. The photoelectrochemical characterisation shows that adding yttrium produces an enhanced charge separation efficiency in the bulk which can be attributed to a higher donor density in the structure, and a 92.5% higher photocurrent density is obtained for the 5%Y-CuWO4 photoelectrode when compared to the pure CuWO4 photoelectrode for the oxygen evolution reaction at 1.3 V vs RHE. This work shows that doping CuWO4 with yttrium is an effective approach to improve the poor charge separation presented by pure CuWO4 photoelectrodes.

Photothermal‐boosted polaron transport in Fe2O3 photoanodes for efficient photoelectrochemical water splitting

AbstractIntroduction of the photothermal effect into transition‐metal oxide photoanodes has been proven to be an effective method to improve the photoelectrochemical (PEC) water‐splitting performance. However, the precise role of the photothermal effect on the PEC performance of photoanodes is still not well understood. Herein, spinel‐structured ZnFe2O4 nanoparticles are deposited on the surface of hematite (Fe2O3), and the ZnFe2O4/Fe2O3 photoanode achieves a high photocurrent density of 3.17 mA cm−2 at 1.23 V versus a reversible hydrogen electrode (VRHE) due to the photothermal effect of ZnFe2O4. Considering that the hopping of electron small polarons induced by oxygen vacancies is thermally activated, we clarify that the main reason for the enhanced PEC performance via the photothermal effect is the promoted mobility of electron small polarons that are bound to positively charged oxygen vacancies. Under the synergistic effect of oxygen vacancies and the photothermal effect, the electron conductivity and PEC performance are significantly improved, which provide fundamental insights into the impact of the photothermal effect on the PEC performance of small polaron‐type semiconductor photoanodes.

Electrodeposition of Zn Zn-doped Cu Cu2O in Acidic and Alkaline Solution and Its Catalytic Activity for Ethanol Electrooxidation

In this study, Zn-doped Cu2O films were synthesized by electrodeposition technique in acidic (pH 4) and alkaline (pH 10) solution. Catalytic activity of the film was evaluated toward ethanol electrooxidation which was carried out using cyclic voltammetry technique. X-ray diffraction (XRD) analysis showed the formation of cubic structure of Cu2O from both conditions. Morphological characterization conducted under a field-emission scanning electron microscope exhibited that Cu2O particles electrodeposited in the acidic condition were smaller compared to those obtained in the alkaline condition. The photoelectrochemical responses, which were recorded using a linear sweep voltammetry technique, showed that the highest photocurrent density was 31.5 mA.cm-2 that obtained at 0.76 V vs. Ag/AgCl using Zn-doped Cu2O film prepared in the acidic condition. The film also possesses a low resistance charge transfer as measured by the electrochemical impedance spectroscopy (EIS) technique. These electrochemical characteristics resulted in a high catalytic performance of the Zn-doped Cu2O film on the ethanol electrooxidation as shown by the high anodic current of 22 mA.cm-2 at 0.968 V. These results indicated that the Zn-doped Cu2O film electrodeposited in the acidic condition has a good catalytic activity towards ethanol electrooxidation process.