Bulk Charge Transfer Research Articles

Triggering Asymmetric Layer Displacement Polarization and Redox Dual-Sites Activation by Inside-Out Anion Substitution for Efficient CO2 Photoreduction.

Sluggish bulk charge transfer and barren catalytic sites severely hinder the CO2 photoreduction process. Seeking strategies for accelerating charge dynamics and activating reduction and oxidation sites synchronously presents a huge challenge. Herein, an inside-out chlorine (Cl) ions substitution strategy on the layered polar Bi4O5Br2 is proposed for achieving layer structure-dependent polarization effect and redox dual-sites activation. Cl ions in the bulk phase shrink the halogen layer interspace by 8‰, triggering asymmetric [Bi4O5]2+ layer displacement polarization, prolonging the average photocharge lifetime to 201.8ps. Meanwhile, surface substituted Cl ions enhance the electron-donating capability of neighboring Bi atoms, activating the intrinsic Bi reduction sites, and increasing H2O molecule adsorption on nearby intrinsic O oxidation site (cal. by 0.105eV), also self-donating as an alien oxidation site. Besides, Cl upshifts the p-band center closer to the Fermi level, facilitating the reactant adsorption. Therefore, the energy barrier for CO2 activation and rate-limiting *COOH intermediate formation steps are significantly decreased. Without cocatalysts and sacrificial reagents, inside-out Cl-substituted Bi4O5Br2 delivers a remarkable CO2-to-CO photoreduction rate of 50.18µmol g-1 h-1, being one of the state-of-the-art catalysts. This finding offers insights into exploiting polarization at the molecular-level and enhances understanding of catalytic site activation.

Pore walls as high-way for efficient bulk charge transfer in porous SrTiO3 single crystals boosting photocatalytic overall water splitting

Suppressing carrier recombination in bulk and facilitating carrier transfer to surface via rational structure design is of great significance to improve solar-to-H2 conversion efficiency. We demonstrate a facile hydrothermal method to synthesize porous SrTiO3 single crystals (SrTiO3-P) with exposed (001) facets by introducing carbon spheres as templates. The obviously increased surface photovoltage and photocurrent response indicate that the interconnected pore walls act as enormous charge transfer “highways”, accelerating carrier transport from bulk to surface. Furthermore, the absence of grain boundaries and high crystallinity could also lower the carrier recombination rate. Thus, the SrTiO3-P photocatalyst loaded with Rh/Cr2O3 as cocatalyst exhibits 1.5 times higher overall water splitting activity than that of solid SrTiO3, with gas evolution rate of 19.99 μmol h−1 50 mg−1 for H2 and 11.37 μmol h−1 50 mg−1 for O2. Additionally, SrTiO3-P also shows superior stability without any decay during cycling testing. This work provides a new insight into designing efficient multicomponent photocatalysts with a single-crystal porous structure.

Fabrication of piezotronic ZnO p-n homojunction via metal/oxygen defects modulation for efficient photoelectrocatalysis

Homojunction is a viable alternative strategy to realize excellent charge separation for enhancing photoelectrocatalytic performance. However, the feasible regulation of the homojunction interface remains challenging. Herein, a ZnO n-p homojunction with the piezotronic effect is constructed via an in-situ solvothermal method for enhancing photoelectrocatalytic activity. ZnO nanorods are transformed from n-type to p-type ZnO nanoparticles with zinc vacancies, leading to the n-p homojunction. The optimal NPZ-36 exhibits a superior photocurrent density of 1.56 mA/cm2 at 1.23 V vs. RHE and a high incident photon to current conversion efficiency of 75 % at 360 nm. Impressively, with the merits of inherent piezoelectric and photocatalytic properties of wurtzite ZnO, the piezoelectric-enhanced photoelectrochemical activity originates from the simultaneous promotion of bulk charge transfer and interfacial charge separation in ZnO n-p homojunction. The photocurrent density of NPZ-36–900 can reach to 2.02 mA/cm2 under the stirring rate of 900 rpm, which is 2.1 times higher than that of pure ZnO photoanode.

In-situ electron capture by surface Co-Ci to facilitate the solar water splitting of Fe2O3

Surface co-catalyst has been widely used to improve the performance of hematite for solar water splitting. However, the specific working mechanism for co-catalyst has not yet been extensively studied, especially lacking for in-situ information. Here we report a Co-Ci/Zr-Fe2O3 (LV) photoanode for efficient water splitting and probe the working mechanism of surface Co-Ci by in-situ X-ray absorption spectroscopy (XAS) under illumination. The low vacuum treatment and the Zr-doping in Co-Ci/Zr-Fe2O3 (LV) can significantly increase the donor density and then facilitate the bulk charge transfer, while the surface Co-Ci co-catalyst can greatly reduce the electron-hole recombination and then lower the onset potential. In-situ XAS reveals that under illumination, the photon-excited electrons will be quickly transferred to the Co sites in Co-Ci, while the excited holes will be left on Fe to form the high-valence Fe4+ to enhance the oxidation capability. As a result, the combined Co-Ci/Zr-Fe2O3 (LV) photoanode shows a quick bulk charge transfer and a low surface charge recombination, leading to a high photocurrent density of 4.10 mA/cm2 (1.23 VRHE) and a low onset potential of 0.85 VRHE with good stability.

Gradient‐Tuned VO4 Vacancies in BiVO4 Photoanode for Boosting Bulk Hole Transport and Oxygen Evolution Reaction Performance

AbstractAlthough bismuth vanadate (BiVO4) photoanode has been widely used, the solar‐driven oxygen evolution reaction (OER) performance is constrained due to the substantial bulk recombination and poor mobility of charge carriers. Herein, a facile solvothermal post‐treatment approach that employs N,N‐dimethylformamide (DMF) is developed to induce a VO4 vacancy gradient from bulk to surface of BiVO4 film, which not only improves the charge diffusion but also establishes an advantageous upward band gradient to promote the bulk hole transport. Under Air Mass 1.5 Global (AM1.5G) simulated solar illumination, the optimized BiVO4 photoanode with a VO4 vacancy gradient (denoted as B(VO)1‐δ) exhibits excellent OER performance with a charge separation efficiency of 74.4% at 1.23 V versus reversible hydrogen electrode (RHE) and incident‐photon‐to‐current conversion efficiency of 30.7% at 445 nm, 1.2 and 1.4 times higher than that of the pristine BiVO4, respectively. After loading nickel‐iron hydroxyl oxide (NiFeOOH) as a cocatalyst, the photocurrent density of B(VO)1‐δ escalates to 5.92 mA cm−2 in a hole scavenger (Na2SO3) solution and 5.07 mA cm−2 in a potassium borate buffer solution at 1.23 V versus RHE, far superior to the pristine BiVO4. This work highlights that the gradient‐tuned VO4 vacancies can effectively modulate the bulk band structure and charge transfer in BiVO4 photoanode, providing a new strategy for boosting solar water splitting performance.

Electronic Reconstruction via Low‐Degree Fluorination for High‐Performance Zinc‐Ion Battery

AbstractThe development of transition metal oxide cathodes with high capacity and ultralong lifespan is one of the keys to promoting the performance of aqueous zinc–ion batteries, but it remains a crucial challenge. Herein, cobalt oxide is applied as an example to demonstrate that low‐degree fluorination is a novel approach to synergistically boost charge storage kinetics and stability. Specifically, partial substitution of O2− with F− intensifies electron delocalization of Co 3d orbitals, which reduces bulk charge transfer impedance and endows surface active sites with higher reactivity, thus achieving boosted redox kinetics and energy density. Moreover, the modification of coordination structure with the highest‐electronegativity F− can effectively inhibit irreversible phase transition and structural deformation, which assures significantly optimized cycling stability. As a result, the fluorinated Co3O4 demonstrates a distinctly improved specific capacity of 406 mAh g−1 at 1 A g−1, approximately a threefold increase compared to one of pristine Co3O4 (131 mAh g−1). The assembled fluorinated Co3O4//Zn battery delivers an ultrahigh energy density of 658 Wh kg−1 at 3.5 kW kg−1 and 95.7% capacity retention after 10 000 cycles. This work offers a new understanding of the electronic engineering of metal oxides toward high‐performance energy storage applications.

Enhanced bulk and interfacial charge transfer in Fe:VOPO4 modified Mo:BiVO4 photoanodes for photoelectrochemical water splitting

Bismuth vanadate (BiVO4) is a promising photoanode material for photoelectrochemical (PEC) water oxidation. However, its performance is greatly hindered by poor bulk and interfacial charge transfer. Herein, to address this issue, iron doped vanadyl phosphate (Fe:VOPO4) was grafted on molybdenum doped BiVO4 (Mo:BiVO4) for significantly enhancing charge transfer and oxygen evolution kinetics simultaneously. Consequently, the resultant Fe:VOPO4/Mo:BVO4 photoanode exhibits a remarkable photocurrent density of 6.59 mA cm−2 at 1.23 V versus the reversible hydrogen electrode (VRHE) under AM 1.5G illumination, over approximately 5.5 times as high as that of pristine BiVO4. Systematic studies have demonstrated that the hopping activation energy of small polarons is significantly reduced due to the Mo doping, resulting in accelerated bulk charge transfer. More importantly, the deposition of Fe:VOPO4 promotes the interfacial charge transfer between Mo:BiVO4 and Fe:VOPO4 via the construction of V−O−V and P−O bonds, in addition to facilitating water splitting kinetics. This work provides a general strategy for optimizing charge transfer process, especially at the interface between photoanodes and cocatalysts.

Solvation structure dependent ion transport and desolvation mechanism for fast-charging Li-ion batteries.

The solvation structures of Li+ in electrolytes play prominent roles in determining the fast-charging capabilities of lithium-ion batteries (LIBs), which are in urgent demand for smart electronic devices and electric vehicles. Nevertheless, a comprehensive understanding of how solvation structures affect ion transport through the electrolyte bulk and interfacial charge transfer reactions remains elusive. We report that the charge transfer reaction involving the desolvation process is the rate-determining step of the fast charging when ion conductivity reaches a certain value as determined by investigating electrolytes with eight conventional solvents (linear/cyclic carbonate/ether). The physicochemical characteristics of solvent molecules can result in strong ion-ion, moderate ion-dipole, strong ion-dipole, and weak ion-dipole/ion-ion interactions, respectively, in which the speed of the charge transfer reaction follows the above order of interactions. Among all solvents, dioxolane (DOL) is found to enable strong ion-ion interactions in electrolytes and thus exhibits exceptional fast-charging performance and it can still retain 60% of the initial capacity at 20C (1C = 170 mA g-1) with a polarization of merely 0.35 V. Further experimental characterization and theoretical calculation reveal that the aggregates in DOL electrolytes contribute to hopping assisted ion transport and facilitate the desolvation process of Li+. Our results deepen the fundamental understanding of the behavior of Li+ solvation and provide an effective guiding principle for electrolyte design for fast-charging batteries.

Enhancing photocatalytic efficiency with hematite photoanodes: principles, properties, and strategies for surface, bulk, and interface charge transfer improvement

This review systematically explores various strategies aimed at enhancing charge transfer at different levels—bulk, surface, and interfaces of hematite. The examination encompasses diverse approaches, and assesses their impact on mitigating the identified issues.

Chimie Douce Derived K-Based P2-Type Transition Metal(s) Layered Oxides for Secondary K-Ion Batteries

Owing to great societal and technological benefits, there has been a remarkable growth in the industrial demand for enhanced energy storage for many target applications including electric vehicles, aerospace applications, and portable electronics. Secondary K-ion batteries (KIBs) are among the potentially inexpensive candidates for energy storage systems beyond state-of-the-art Li-ion batteries (LIBs). Electrochemical cells based on mobile carrier K+ can provide efficient energy storage because of comparative ionic diffusion in bulk and swift charge transfer at the interface due to weak Lewis’s acidity.1,2 Despite various advantages over LIBs and NIBs, the roadblock of practical KIB implementation lies in identifying suitable cathodes that reversibly (de)intercalate K+ at optimum voltage, swift rate, and with prolonged cycle life.Despite constant efforts to develop new cathodes for K+ -ion batteries, several challenges such as low concentrations of K-ions due to strong electrostatic repulsions between the K+ - K+ ions and difficulty in preparation from direct synthesis routes3 limit its practical application. In this scenario, we have adopted the chimie douce (soft chemistry) method to design the novel layered transition metal oxide cathode from the parent P2 type Na-based system. In addition, we have probed the ion exchange mechanism using X-ray diffraction and transmission electron microscopy (TEM) techniques. Rietveld analysis confirmed the structure having a P2-type stacking sequence with hexagonal symmetry and P6/3mmc space group. Further, we have successfully examined the chemical ion-exchanged novel layered P2- K2/3Co1/3Mn2/3O2 as a cathode for KIB at ambient and high temperatures. It delivered a good capacity (~70 mAh/g) with an average redox potential of 3.0 V along with good cycling stability and coulombic efficiency (CE) in temperature ranging from 25-50 ºC. Ex-situ X-ray diffraction analysis and potentio/galvanostatic titration techniques were used to analyse the K+ insertion mechanism. This study can assist in developing new insertion K+ host materials for viable and reliable practical applications.

Boosting bulk charge transport of CuWO4 photoanodes via Cs doping for solar water oxidation

Copper tungstate (CuWO4) is a promising photoanode for photoelectrochemical (PEC) water splitting due to its appropriate energy band position and broad light absorption range. However, the inherent unfilled 3d atomic orbital of Cu acts as a natural electron-hole recombination site, significantly constraining the PEC performance of CuWO4. Herein, Cs atoms with complete atomic orbitals are doped into CuWO4 in order to obtain better bulk charge separation capability. As a result, the photocurrent of Cs@CuWO4 increases from 0.57 to 0.99 mA cm−2 compared to CuWO4 at 1.23 V vs. reversible hydrogen electrode (RHE) under AM 1.5G illumination, as well as the bulk charge transfer efficiencies rising from 13.5% to 19.3%. In addition, density of states (DOS) calculations further prove that the introduction of Cs atoms effectively suppresses the contribution of Cu 3d orbitals at the Fermi level. This work offers a valuable reference for the advancement of CuWO4 as the next-generation PEC photoanode material.

Unravelling the role of the combined effect of metallic charge transfer channel and SiOx overlayer in the Zr/Si-Fe2O3:Au:SiOx nanorod arrays to boost photoelectrochemical water splitting

Hematite (α-Fe2O3) based photoanodes have been extensively studied due to various intriguing features that make them viable candidates for a photoelectrochemical (PEC) water splitting photoanode. Herein, we propose a Zr-doped Fe2O3 photoanode decorated with facilely spin-coated Au nanoparticles (NPs) and microwave-assisted attached Si co-doping in conjunction with a SiOx overlayer that displayed a remarkable photocurrent density of 2.01 mA/cm2 at 1.23 V vs. RHE. The kinetic dynamics at the photoelectrode/electrolyte interface was examined by employing systematic electrochemical investigations. The Au NPs played a dual role in increasing PEC water splitting. First, the Schottky interface that was formed between Au NPs and Zr-Fe2O3 electrode ensured the prevention of electron flow from the photoanode to the metal, increasing the number of available charges as well as suppressing surface charge recombination. Second, Au extracted photoholes from the bulk of the Zr-Fe2O3 and transported them to the outer SiOx overlayer, while the SiOx overlayer efficiently collected the photoholes and promoted the hole injection into the electrolyte. Further, Si co-doping enhanced bulk conductivity by reducing bulk charge transfer resistance and improving charge carrier density. This study outlines a technique to design a metallic charge transfer path with an overlayer for solar energy conversion.

Octahedral Tilt Enables Efficient and Stable Fully Vapor‐Deposited Perovskite/Silicon Tandem Cells

AbstractThermal evaporation can significantly facilitate scalable, uniform, and conformal perovskite film, particularly well‐suited for the preparation of perovskite/silicon (Si) tandem solar cells . However, the perovskite material easily induces a phase transition from a photoactive phase to a photoinactive phase, limiting the development of the stability and efficiency of tandem cells. Introducing lead chloride (PbCl2) into wide‐bandgap perovskite materials is beneficial for the fabrication of efficient and stable light‐absorbing materials, but the microscopic mechanism of the effect of PbCl2 on perovskite is still unclear. The study here reports evidences that the addition of PbCl2 to improve perovskite film stability and optoelectronic performance is due to the minor octahedral tilting of the perovskite structure are reported. It also demonstrates that this strategy accelerates interfacial charge transfer and carrier diffusion in the perovskite bulk and heterojunction interfaces. Therefore, the wide‐bandgap perovskite solar cells (PSCs) prepared by adding PbCl2 exhibit a champion power conversion efficiency (PCE) of 17.80%. The PSCs retain 97% of their performance following 200 h of operation at the maximum power point under full 1‐sun illumination. Finally, monolithic perovskite/Si tandem cells with record PCEs of 27.43% and an open‐circuit voltage of 1.817 V are fabricated.

Kinetic study of the enhanced photoelectrochemical properties of microwave-assisted Al and Si co-doped Zr-Fe2O3 photoanodes

Unintended metal oxide layer development during co-doping has been suggested as being highly effective in intensifying the oxygen evolution reaction. Herein, we studied the influence of microwave-assisted co-doping of trivalent Al3+ and tetravalent Si4+ into Zr-Fe2O3 photoanode for effective photoelectrochemical (PEC) performance. The Si co-doping showed effective diffusion into the hematite bulk during high-temperature quenching. Relative to SiOx, an Al2O3 layer notably passivated the surface defects, whilst Si4+ co-doping markedly improved the bulk charge transfer features, compared to Al3+ co-doping. Because of the active passivation effect of the Al2O3 layer, the photocurrent density of Al/Zr-Fe2O3 photoanode was considerably increased at lower potentials. In specific, the Al/Zr-Fe2O3 photoanode displayed an almost 100% enhancement in surface charge transfer rate constant than that of the bare Zr-Fe2O3 at 1.23 VRHE. The comprehensive experimental results provided evidence of the consequence of tri/tetravalent co-dopants on charge transfer in the bulk of the hematite and at the photoanode-electrolyte interface. A probable charge transfer mechanism was proposed under illumination to demonstrate how the Si and Al microwave-assisted attachment impacted the photogenerated charge recombination reduction in the photoanode and subsequently advanced its PEC water splitting performance.

Bifunctional Co-TiO2 co-promoted bulk and interfacial charge transfer of BiVO4 photoanodes for solar water oxidation

The primary causes of photogenerated carrier recombination in BiVO4 photoanodes are the formation of bulk polarons and sluggish water oxidation kinetics. To address these issues effectively, we designed a bifunctional Co-TiO2 to modify the BiVO4 photoanodes. UV–vis DRS and Mott-Schottky results indicate that Co adjusts the band gap of TiO2, and there forms a type-II heterojunction between BiVO4 and Co-TiO2. The experimental tests and theoretical calculations for OER as well as EIS results demonstrate that Co sites in Co-TiO2 provide more reaction sites for the interfacial oxidation reaction, reducing the overpotential. Under the dual action of Co-TiO2, the co-promotion for the migration ability of photogenerated carriers in the bulk and on the surface of BiVO4 photoanode has been realized. This conclusion is supported by analysis of photogenerated charge transfer behavior through transient photocurrent and IMPS. As a result, the photogenerated current density of BiVO4/Co7 %-TiO2 photoanode reaches 4.38 mA cm−2 at 1.23 V vs. RHE under AM 1.5 G illumination, which is four times that of pure BiVO4 photoanodes.

Spatially expanded built-in electric field via engineering graded junction enables fast charge transfer in bulk MnO@Mn3O4 for Na+ supercapacitors

Built-in electric field (BIEF) has recently emerged as a promising strategy for promoting charge transfer by supplying additional coulomb forces. However, the challenge lies in the intelligent control over the thickness and intensity of BIEF to augment these Coulomb forces, thereby enhancing charge transfer in bulk electrodes. Here we deliberately engineer a graded MnO@Mn3O4 junction characterized by a spatially intensified BIEF to accelerate charge transfer over an extended atom layer thickness. This graded MnO@Mn3O4 junction exhibits a phase transition gradient, characterized by a steady decline in Mn valence and work function from shell to core, giving rise to an intense BIEF across the junction. The enhanced BIEF should be ascribed to the spatially accumulated polarization, resulting in an increase in electron delocalization and a decrease in the energy barrier for ion transfer. As a result, the MnO@Mn3O4 manifests improved capacity and rate performance. This work highlights the significance of modulating the BIEF’s thickness and intensity to facilitate charge transfer, thereby pushing the boundaries of electrochemical energy storage.

Pr0.7Ba0.3Co0.8-xFe0.2NixO3−δ perovskite: High activity and durable cathode for intermediate-to-low-temperature proton-conducting solid oxide fuel cells

The development of triple-conductivity (H+/O2−/e−) durable cathode with effective oxygen reduction reaction (ORR) activity is significant to boost the application of proton-conducting solid oxide fuel cell (H–SOFC) at intermediate-to-low-temperature. Herein, we developed the Pr0.7Ba0.3Co0.8-xFe0.2NixO3−δ (x = 0, 0.1, 0.2, 0.3) cathode material with triple-conductivity. Based on the distribution of relaxation time results, it is found that nickel doping enhanced the surface exchange kinetics and boosted bulk charge transfer. As a result, Pr0.7Ba0.3Co0.6Fe0.2Ni0.2O3−δ (PBCFN2) shows better ORR activity with lower polarization resistance (0.043 Ω cm2) and higher power output (1.61 W cm−2) for H–SOFC at 700 °C. Meanwhile, PBCFN2 also shows suitable durability at 600 °C (0.919 A cm−2 for ∼105 h). In general, this research may provide a beneficial instruction for further research and optimization for triple-conducting cathodes in intermediate-to-low-temperature H–SOFC.

Photoelectrochemical water oxidation and methylene blue degradation enhanced by Nb doping and CoPi modification for hematite photoanodes

Nanostructured α-Fe2O3 films doped with niobium and supported with CoPi cocatalyst (Nb-α-Fe2O3 @CoPi) are prepared by hydrothermal growth together with electrochemical deposition. The effect of Nb doping and CoPi cocatalyst modification on the performance of photoelectrochemical water oxidation and methylene blue degradation of α-Fe2O3 is studied in detail. It shows that Nb doping and CoPi modification toward α-Fe2O3 not only enhances its light absorption, but also improves its electrical properties, including conductivity, bulk charge separation efficiency and charge transfer efficiency at the electrode/electrolyte interface. When used as photoanode for photoelectrochemical water oxidation, the Nb-α-Fe2O3 @CoPi photoanodes show a negative shift of 540 mV in the onset potential in comparison with the pristine α-Fe2O3 films. At the same time, the photocurrent density (at 1.6 V, vs. RHE) of Nb-α-Fe2O3@CoPi is more than three times that of the pristine α-Fe2O3, reaching 1.44 mA·cm−2. In addition, the obtained Nb-α-Fe2O3 @CoPi photoanodes also show excellent performance in visible light-driven photoelectrochemical degradation of methylene blue, a common pollutant in wastewater. For example, a degradation rate of 98% is achieved in 2 h by the Nb-α-Fe2O3 @CoPi, which is 3.6 times that of the pristine α-Fe2O3 (26%).

Development of functionalized CoOx-NiFe LDH bi-layers to improve the photoelectrochemical water oxidation property of n-Si photoanode

Tandem of photocathode (p-type semiconductor) and photoanode (n-type semiconductor) is a promising technique for photoelectrochemical (PEC) water overall splitting. However, the sluggish PEC property of the n-type semiconductor usually slow down the whole tandem system. n-silicon is a potential candidate for high-efficiency photoanode fabrication, but it is limited by the overlarded water oxidation reaction overpotential and the low stability. This work presents a CoOx and NiFe layered double hydroxide (LDH) composite bi-layer modified n-Si photoanode that exhibits excellent PEC performance. Experimental analysis and theoretical calculation results show that the CoOx-NiFe LDH bi-layer accelerates the bulk charge transfer as well as regulates the interfacial charge transfer by a synergistic effect. The prepared n-Si-CoOx-NiFe LDH photoanode exhibits a negative onset potential of 0.95 V (vs. RHE), a photocurrent of 12.2 mA cm−2 at 1.23 V (vs. RHE) and a saturated photocurrent of 41 mA m−2. In addition, the n-Si-CoOx-NiFe LDH photoanode can keep well stability for overall water splitting with nearly 100 % faradaic efficiency. This composite CoOx/NiFe LDH modification strategy provides a promising approach to improve the PEC performance of photoanodes.

Photo/Thermal Dual‐Activation Improves the Photocurrent of Bismuth Vanadate for PEC Water Splitting

AbstractMaking full use of the whole sunlight spectrum and developing photoanode with high performance are the two crucial challenges to realizing the industrial application of PEC water splitting. Thermal‐activation is an ideal way to realize the full use of the whole sunlight spectrum as the thermal energy is easily generated by the long wavelength sunlight. Photo‐activation is an effect way to enhance the PEC performance of BiVO4 through the synergistic effects of its bulk charge transfer and surface properties. In this work, the combining of thermal‐activation and photo‐activation (dual‐activation) was conducted on the BiVO4 photoanode to improve its photocurrent performance. The results indicate that the dual‐activation dramatically improved the photocurrent density of BiVO4 photoanode from 0.62 mA cm−2 to 1.32 mA cm−2 at 1.23 VRHE, and the improvement could be ascribed to the synergistic effects of Ddonor enhancement and diminished Fermi level pinning effect. Besides, the charge transfer process in the BiVO4 photoanode was also effectively facilitated by the dual‐activation.