共查询到20条相似文献,搜索用时 31 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(63):27012-27022
Developments of promising photocatalyst for PEC water oxidation gain significant interest in the research field of PEC water splitting. The BiVO4 has been envisioned as suitable photocatalyst material for the PEC water oxidation due to suitable bandgap with favorable band edge positions. Nevertheless, the poor electron-hole separation and low charge transfer efficiency of BiVO4 yield sluggish surface catalysis reaction. Herein, facile electrodeposition and annealing techniques are proposed to fabricate W-doped BiVO4 photoanode coupled with FeOOH (W–BiVO4/FeOOH) for efficient photocatalytic water oxidation. This synthesis is simple, cost-effective and less time consuming. The doping concentration of W and deposition time of FeOOH are optimized to improve photocatalytic ability of BiVO4. At 1.23 V vs. reversible hydrogen electrode (RHE) under 1 sun illumination, the W–BiVO4/FeOOH photoanode exhibits a high photocurrent density of 2.2 mA/cm2, which is seven folds higher than that of the pristine BiVO4 photoanode (0.31 mA/cm2 1.23 V vs. RHE). The enhanced photocatalytic ability of W–BiVO4/FeOOH photoanode is due to the enhanced charge transport properties and synergistic effects of W doping and FeOOH deposition. The excellent long-term stability with the photocurrent density retention of 90% after continuous light illumination for 1000 s is also achieved for the W–BiVO4/FeOOH photoanode. 相似文献
2.
《International Journal of Hydrogen Energy》2020,45(13):7779-7787
We report the application of plasmonic Bi nanoparticles supported rGO/BiVO4 anode for photoelectrochemical (PEC) water splitting. Nearly, 2.5 times higher activity was observed for Bi-rGO/BiVO4 composite than pristine BiVO4. Typical results indicated that Bi-rGO/BiVO4 exhibits the highest current density of 6.05 mA/cm2 at 1.23 V, whereas Bi–BiVO4 showed the current density of only 3.56 mA/cm2. This enhancement in PEC activity on introduction of Bi-rGO is due to the surface plasmonic behavior of BiNPs, which improves the absorption of radiation thereby reduces the charge recombination. Further, the composite electrode showed good solar to hydrogen conversion efficiency, appreciable incident photon-to-current efficiency and low charge transfer resistance. Hence, Bi-rGO/BiVO4 provides an opportunity to realize PEC water splitting. 相似文献
3.
《International Journal of Hydrogen Energy》2022,47(7):4375-4385
Monoclinic phase of BiVO4 is a promising photoanode material for photoelectrochemical (PEC) water splitting, but its sluggish water oxidation kinetics and frequent bulk charge recombination greatly reduce its efficiency of PEC water splitting. A novel BiVO4/NiO/rGO photoanode was very simply prepared by electrodeposition, solution immersion and spin coating methods, in particular, the solution immersion method to loading NiO has never been reported in PEC research. Compared with BiVO4, the photocurrent density of the ternary photoanode reaches 1.52 mA/cm2 at 1.23 V vs RHE, which is 2.41 and 1.39 times higher than that of pure BiVO4 and binary BiVO4/NiO photoanode, respectively. The onset potential of the ternary photoanode shows a significant cathodic shift of 130 mV compared with the BiVO4 photoanode. Moreover, the measured incident photon-to-current efficiency (IPCE) value reaches 50.52% at λ = 420 nm. The improvement is attributed to the type-II heterojunction formation that enhances the separation efficiency of electron/hole and the rGO decoration that accelerates the electron transfer and provides more active sites for gas adsorption. 相似文献
4.
《International Journal of Hydrogen Energy》2020,45(56):31902-31912
Bismuth vanadate (BiVO4) is being widely identified as a leading n-type semiconductor material for photoelectrochemical (PEC) water splitting. Nevertheless, achieving efficient PEC water oxidation process through BiVO4 photoanode still faces serious challenge such as severe electron-hole recombination. In this case, PEC activity of BiVO4 photoanode was enhanced by decoration of three-dimensional CoMn-layered double hydroxide (CoMn-LDH) nanoflakes on the BiVO4 surface via a facile electrodeposition process. It was suggested that CoMn-LDH played a synergistic effect on broadening internal light absorption, which accelerated injection of holes carrier to electrolyte and alleviated the electron-hole recombination, resulting in expediting faster PEC water oxidation reaction kinetics. Consequently, the photocurrent density of BiVO4/CoMn-LDH photoanode achieved 2.69 mA cm−2 at 1.23 VRHE, 2.45 times higher than the pristine BiVO4. What's more, 220 mV negative-shift took place on onset potential that was further decreased to 0.31 VRHE. The vastly enhanced PEC performance was also prioritized to those of Co and Mn single relatives. This work demonstrated that the synergistic BiVO4/CoMn-LDH as a capable candidate material, can be utilized for effective PEC water splitting. 相似文献
5.
《International Journal of Hydrogen Energy》2022,47(97):40961-40971
Co-catalyst decoration and heteroatom doping techniques are largely applied to enhance photoelectrochemical catalytic ability of BiVO4. Zeolitic imidazolate framework 67 (ZIF67) with cobalt center and high specific area is promising as co-catalyst of BiVO4. In this study, it is the first time to synthesize different sizes of ZIF67 polyhedrons as co-catalyst of W-doped BiVO4 (WBVO) using electrodeposition and hydrothermal techniques to catalyze water oxidation. Decorating ZIF67 on WBVO (WBVO/ZIF67) can enhance light absorption intensity, create active sites, and suppress recombination to improve water oxidation kinetics. The highest photocurrent density of 2.30 mA/cm2 at 1.23 V versus reversible hydrogen electrode (VRHE) is obtained for WBVO/ZIF67 electrode with the smallest size of ZIF67 in electrolyte without hole scavenger, while the WBVO electrode only presents the photocurrent density of 0.9 mA/cm2 at the same condition. The smallest size of ZIF67 can provide largest contacts with WBVO and electrolyte and create efficient charge transfer paths and numerous active sites. The photocurrent retention higher than 80% is achieved for WBVO/ZIF67 electrode under continuous illumination for 5000 s. The highly improved photoelectrochemical catalytic ability of WBVO/ZIF67 confirms the feasibility of applying ZIF67 as co-catalyst and indicates the significance of sizes of ZIF67 co-catalyst on catalytic ability. 相似文献
6.
《International Journal of Hydrogen Energy》2020,45(51):26746-26757
Photoelectrochemical water splitting using bismuth vanadate (BiVO4) is drawing attention but on account of presence of high charge recombination and poor water oxidation kinetics its performance is restricted. Present study attempts to understand the role of dopant Ni on BiVO4 in a) reducing the charge recombination and b) to improve water oxidation kinetics. Ni doped BiVO4 thin films are prepared via electrodeposition method and photoelectrochemical properties are investigated in 0.1 M phosphate buffer solution with and without sodium sulfite hole scavenger. Photocurrent density of 1.36 mA/cm2 at 1.23 V vs. RHE has been obtained using 1.5% Ni doped BiVO4. This sample also offered lower flat band potential, high open circuit potential and applied bias photon-to-current conversion efficiency. Addition of hole scavenger significantly increases the photoelectrochemical performance. Ni as a dopant therefore can play an important role in not only suppressing the electron-hole pair recombination but also in offering significantly enhanced photoelectrochemical response. 相似文献
7.
《International Journal of Hydrogen Energy》2023,48(13):5152-5165
Bismuth vanadate (BiVO4) with suitable conduction/valence band edges and band gap has been largely applied on photoelectrochemical catalytic water oxidation as clean energy technology. To solve the short charge diffusion length and poor water oxidation kinetics of BiVO4, it is useful to dope heteroatoms and decorate co-catalysts for improving its catalytic ability and electricity. Oxidized zeolitic imidazolate framework 67 (ZIF67) with polyhedron structure and possible composition of cobalt oxide is highly attractive as co-catalyst of BiVO4. In this study, it is the first time to decorate oxidized ZIF67 (O67) as co-catalyst on W-doped BiVO4 (WBVO) using the drop casting technique for catalyzing photoelectrochemical water oxidation. Different amounts of ZIF67 are decorated on WBVO using the drop-casting technique. The O67 is merged into WBVO nanorod arrays after converting ZIF67 into O67 using the annealing process. The highest photocurrent density of 2.08 mA/cm2 at 1.23 V versus reversible hydrogen electrode (VRHE) is obtained for the optimal WBVO/O67 electrode in the electrolyte without hole scavenger, while the WBVO electrode only shows the photocurrent density of 1.20 mA/cm2 at the same condition. The decoration of O67 can increase light absorption, generate active sites, and reduce charge recombination. The photocurrent retention higher than 92% is achieved for the WBVO/O67 electrode under continuous illumination for 5000 s. The greatly enhanced photoelectrochemical catalytic ability of WBVO/O67 implies the feasibility of utilizing oxidized ZIF67 as a co-catalyst to accelerating water oxidation. 相似文献
8.
《International Journal of Hydrogen Energy》2019,44(45):24642-24652
BiVO4 is an ideal photoanode material for solar-driven photoelectrochemical (PEC) water splitting but it easily suffers from the recombination of photogenerated electrons and holes due to its low carrier mobility thus cause low efficiency of PEC water splitting. Herein, the BiVO4/CdS/NiCo-LDH photoanode was prepared by combining methods of metal organic decomposition, chemical and electrodeposition. The photoanode photocurrent density reaches 2.72 mA cm−2 at 1.23 V (vs. RHE), which is 3.6 folds of pure BiVO4 photoanode and onset potential shifts 450 mV toward cathodic. The incident photon-to-electron conversion efficiency (IPCE) value is 2.86 folds of BiVO4, the calculated photon–to–current efficiency (ABPE) is 1.24% at 0.62 V (vs. RHE). The obtained results are higher than that of most BiVO4 based photoanodes published so far. The enhancement benefits from increase of visible light absorption capacity, enhancement of separation efficiency of photoexcited electron-hole and fast transfer of holes accumulated on electrode/electrolyte surface for water oxidation, which has been confirmed by calculating carrier density and carrier transport rate. 相似文献
9.
《International Journal of Hydrogen Energy》2022,47(2):940-949
Photoelectrochemical (PEC) water splitting is an effective way of converting solar energy into hydrogen (H2) energy. However, the carriers’ transmission and the reaction kinetics of the photoelectrode are dilatory, which will influence the conversion efficiency of solar energy to H2. In this work, a novel of BiVO4/Co1-XS photoanode was successfully fabricated through the successive ionic layer adsorption reaction. The photocurrent density of optimal sample BiVO4/Co1-XS (2.9 mA cm?2 at 1.23 VRHE) has reached up to 5 times that of pure BiVO4, and the applied bias photon to current conversion efficiency increased from 0.04% (BiVO4) to 0.4% (BiVO4/Co1-XS). The superior PEC performance of the BiVO4/Co1-XS photoanode is mainly related to the improved conductivities and reaction kinetics. The charge injection efficiency of BiVO4/Co1-XS grew to about 80%, and the charge separation efficiency was up to 34%, revealing that the decoration of Co1-XS could significantly accelerate the transfer speed of photogenerated carriers from the electrode surface to the electrolyte. This work provided an efficient and simple scheme for improving the PEC performance of photoanode, through reasonable design and research. 相似文献
10.
《International Journal of Hydrogen Energy》2019,44(52):28184-28193
Photoelectrochemical (PEC) water splitting using earth-abundant semiconductor offer a promising strategy to produce the sustainable clean energy. Herein, we successfully engineered BiVO4 photoanode with Fe-doped CoP oxygen evolution catalysts (BiVO4–Fe/CoP) for the first time. Fe/CoP catalysts could significantly break the kinetic limitations of BiVO4, contributing to the enhanced charge injection efficiencies and charge carrier density. The rational heterostructure has boosted the photocurrent density and incident photon-to-current conversion efficiency (IPCE) to 2.16 mA/cm2 and 43% (7 times than that of the bare BiVO4), respectively. Meanwhile, the BiVO4–Fe/CoP photoanode also exhibited the desirable long-term stability during PEC water oxidation for 4 h. The results prove the feasibility of BiVO4–Fe/CoP configuration, which further provided a novel approach towards the development of efficient PEC water oxidation system. 相似文献
11.
《International Journal of Hydrogen Energy》2022,47(94):39796-39828
Photoelectrochemical (PEC) water splitting, and carbon dioxide (CO2) utilization devices have attracted immense attention as sustainable technologies for the generation of hydrogen (H2) fuel and value-added chemicals feedstock. Among numerous semiconductors, bismuth vanadate (BiVO4) has emerged as a promising photoanode owing to its fascinating features such as high chemical stability, straddling band alignment with water redox levels, eco-friendly, and cost-effectiveness. However, sluggish oxidation kinetics, photo-corrosive nature, low electronic conductivity, and short carrier diffusion length limit its commercialization on the PEC horizon. To mitigate these inadequacies, several strategies have emerged such as novel heterojunctions, doping with unique materials, interface modulation, morphology, facet orientation, co-catalyst loading for surface engineering, etc. to realize the outstanding cost-to-efficiency ratios and long-term stability of PEC devices. The review highlights the recent advancement in BiVO4-based photoanodes in last five years (2018–2022) and their utilization in the single absorber and unexplored tandem PEC systems towards boosted water splitting and CO2 reduction. A discussion on theoretical studies of BiVO4-based PEC systems elucidates the microscopic mechanism of promotion effect of the bulk/interface/surface strategies on surface catalysis as well as interfacial charge transfer in boosting oxidation kinetics. Moreover, this review addresses the versatility of the BiVO4-based photoanode for the novel yet commercially viable PEC applications. This review will provide a broad avenue in designing highly durable, and scalable BiVO4-based systems toward various PEC energy conversion devices. 相似文献
12.
《International Journal of Hydrogen Energy》2019,44(16):7905-7914
BiVO4 has been widely applied as photocatalysts for water oxidation, owing to preferable band configuration and small band gap for absorbing wide range of light. Synthesizing BiVO4 is usually based on wet routes, which are more complex and require extra steps for separating photocatalysts from solutions. A novel solid-state synthesis is firstly proposed in this study to efficiently synthesize BiVO4 by simply mixing bismuth and vanadium salts without other mediums and directly annealing the mixture at 450°C. Heteroatom-doping of BiVO4 is also achieved by annealing the mixture of W and Mo salts along with bismuth and vanadium precursors to increase the carrier concentration and accelerating the charge transfer. The W and Mo co-doped BiVO4 electrode with the W:Mo ratio of 1:1 shows the highest photocurrent density of 0.21 mA/cm2 at 1.23 V versus reversible hydrogen electrode and the smallest onset potential of 0.686 V versus reversible hydrogen electrode under air mass 1.5 solar illumination. This study successfully realizes the efficient fabrication of BiVO4 and the incorporation of W and Mo dopants using the solid-state synthesis. Applying this manner cannot only reduce the synthesis time but also provide more precise control of the element composition. Further developments of the co-catalyst/photocatalyst system are expected to be realized by applying this novel solid-state synthesis. 相似文献
13.
《International Journal of Hydrogen Energy》2022,47(40):17600-17610
The photoelectrochemical water oxidation ability of BiVO4 is usually restrained by its low separation efficiency of the photogenerated charge and slow kinetics for water oxidation. Here, FeCoS2 bimetallic sulfide nanoparticles are successfully coated on BiVO4 photoanode to address these problems. The photocurrent density of FeCoS2/BiVO4 photoanode is 3.08 times that of BiVO4 photoanode. Furthermore, the charge separation efficiency can reach 75% and the charge injection efficiency reaches nearly 78%. The onset potential of FeCoS2/BiVO4 shifts 300 mV negatively, while the incident photon-to-electron conversion efficiency value of FeCoS2/BiVO4 is 2.86 folds of BiVO4. The enhancement benefits from the loading of FeCoS2, which promotes the separation of photogenerated electron and hole, and inhibits the recombination of photogenerated charge and hole. 相似文献
14.
《International Journal of Hydrogen Energy》2021,46(71):35280-35289
In this work, a FeOOH/Au/BiVO4 photoanode was fabricated through dual modification with Au nanoparticles (NPs, ∼5 nm) and FeOOH nanoneedles (NNs) on nanoporous BiVO4 surface. Both the Au NPs and FeOOH NNs were distributed uniformly onto the BiVO4 by using the electrodeposition and chemisorption routes, respectively. After parameter optimization, the FeOOH/Au/BiVO4 photoanode displayed a photocurrent density of 4.64 mA cm−2 at 1.23 VRHE, which was 3.74 times higher than the pristine BiVO4 one. Besides, the FeOOH/Au/BiVO4 photoanodes also displayed a maximum H2 yield amount of 23.9 μmol cm−2 h−1. The significantly enhanced performance could be attributed to the following reasons: Introduction of Au NPs enhanced the visible light absorption through localized surface plasmon resonance (LSPR) effect; the photo-excited “hot electrons” of Au NPs were more likely to flow into the conduction band (CB) of BiVO4 via a direct electron transfer mechanism, leading to an improvement of the charge separation/transfer efficiency; surface modification of FeOOH extracted photogenerated holes, leading to an acceleration of the surface catalytic kinetics. In a word, the present study suggests that co-sensitization of Au NPs and FeOOH might be an effective method for improving the PEC water oxidation kinetics of BiVO4 photoanodes. 相似文献
15.
《International Journal of Hydrogen Energy》2022,47(44):18992-19004
Bismuth vanadate has been extensively investigated as a potential visible light photoanode for PEC water splitting. The performance of BiVO4 is restricted by fast charge recombination and slow oxygen evolution reaction kinetic. To address these issues, hierarchical SnO2 (HSN) mesoporous support is developed via a novel sol-electrophoretic approach, and BiVO4 film is decorated with silver nanorods (Ag NRs). The photocurrent density of HSN/BiVO4 photoanode is 3.98 mA/cm2 at 1.23 V vs. reversible hydrogen electrode (RHE) and onset potential (Vonset) of 0.5 V vs. RHE. The PEC performance is attributed to the appropriate band alignment between SnO2 and BiVO4, as well as the hierarchical structure of SnO2. Ag-HSN/BiVO4 photoanode shows photocurrent density of 4.30 mA/cm2 at 1.23 V vs. RHE and Vonset of 0.28 V vs. RHE. The enhanced photocurrent and negatively shifted Vonset can be attributed to radiative localized surface plasmon resonance decay and catalytic effect of Ag NRs, respectively. 相似文献
16.
Daochuan Jiang Lei Zhang Qiudi Yue Taotao Wang Qiang Huang Pingwu Du 《International Journal of Hydrogen Energy》2021,46(29):15517-15525
BiVO4 is a promising photoanode material for water splitting due to its substantial absorption of solar light as well as favorable band edge positions. However, the poor water oxidation kinetics of BiVO4 results in its insufficient photocurrent density. Herein, we demonstrate the use of CoP nanoparticles for facile surface modification of nanoporous BiVO4 photoanode in potassium borate buffer solution (pH 9.0), which can generate a tremendous cathodic shift of ~430 mV in the onset potential for photoelectrochemical water oxidation. In addition, a remarkable photocurrent density of 4.1 mA cm?2 is achieved at 1.23 V vs. RHE under AM 1.5G illumination. The photoelectrochemical measurement using sodium sulfite as a hole scavenger clearly shows that the greatly improved performances are attributed to the efficient suppression of interfacial charge recombination through loading of CoP catalyst. Moreover, the maximum surface charge injection yield can reach >81% at 1.23 V vs. RHE and the maximum IPCE of CoP/BiVO4 can reach 75.8% at 420 nm, suggesting the potential application of CoP-modified BiVO4 photoanode for overall solar water splitting in cost-effective tandem photoelectrochemical cells. 相似文献
17.
《International Journal of Hydrogen Energy》2019,44(10):4656-4663
Using vanadium oxide (V2O5) inverse opal (IO) as a three-dimensional (3D) electron transporting tunnel, bismuth vanadate (BiVO4) as a light harvester, and Amorphous Nickel Hydroxide (NiOOH) as an oxygen evolution co-catalyst, a V2O5@BiVO4@NiOOH IO architecture was fabricated as an efficient photoanode on a conductive fluorine doped tin oxide (FTO) substrate for photoelectrochemical (PEC) water oxidation. V2O5 is the visible light absorbing photoanodes for water oxidation; however, the efficiency of this compound remains low (∼0.08 mA/cm2 at 1.23 V vs. reversible hydrogen electrode (VRHE)) and the unfavorable surface trap states limits the activity of V2O5 photoelectrodes in a PEC system. We found that the photoactive thin conductive BiVO4 (∼12 nm) in the V2O5 IO greatly enhanced the charge separation efficiency to achieve better PEC water oxidation through modification of the surface states. The subsequent addition of NiOOH as an effective Oxygen evolution catalyst subsequently reduces the large overpotential and generates the photocurrent density of 1.14 mA/cm2 at 1.23 VRHE. Electrochemical impedance spectroscopy (EIS) evidenced that NiOOH deposition can substantially lower the charge transfer resistance (Rct) at the semiconductor interface. Specifically, the consecutive and ordered morphology renders direct conduction pathways for the extraction of photogenerated electron/hole pairs and the convenient structure to penetrate the photogenerated carriers toward the semiconductor surface over the electrolyte. It is expected that the uninterrupted pathways will improve the electron transportation and thus the charge collection properties. 相似文献
18.
King-Tsai Jeng Yu-Chang LiuYung-Fang Leu Yu-Zhen ZengJen-Chren Chung Tsong-Yang Wei 《International Journal of Hydrogen Energy》2010
A novel photoelectrochemical cell (PEC) for generation of hydrogen via photocatalytic water splitting is proposed and investigated. At the heart of the PEC is a membrane electrode assembly (MEA) integrated with Degussa P25 TiO2 powder as a model photocatalyst for the photoanode and Pt catalyst powder for the dark cathode, respectively. It serves as a compact photocatalytic reactor for water splitting as well as an effective separator for the generated hydrogen and oxygen. The unique characteristic of the MEA-based PEC is that the use of co-catalyst, sacrificial reagent and supporting electrolyte in the cell is totally not required. The novel PEC can be operated without addition of water in the cathode compartment resulting in improved photo conversion efficiency. In addition, the application of a Degussa P25/BiVO4 mixed photocatalyst was found to significantly enhance the hydrogen generation. Further improvements for the MEA-based PEC utilizing solar energy are also proposed. 相似文献
19.
《International Journal of Hydrogen Energy》2019,44(47):25652-25661
Surface decoration of photoanodes with oxygen evolution cocatalysts is an efficient approach to improve the photoelectrochemical water splitting performance. Herein, ultrafine CoOx was selectively immobilized on the surface of BiVO4/WO3 photoanode by using the photogenerated holes to in-situ oxidize Co4O4 cubane. The composited photoanode (CoOx/BiVO4/WO3) displayed an enhanced photoelectrochemical (PEC) water oxidation performance, with a photocurrent density of 2.3 mA/cm2 at 1.23 VRHE under the simulated sunlight irradiation, which was 2 times higher than that of bare BiVO4/WO3. The characterization results for the morphological, optical and electrochemical properties of the photoelectrodes revealed that, the enhanced PEC performances could be attributed to the improved charge carrier separation/transport behaviors and the promoted water oxidation kinetics when the photoelectrodes were loaded with CoOx. 相似文献
20.
The photoelectrochemical performance of a BiVO4 photoanode is limited by its poor charge transport properties, despite other useful optical absorption properties. Modifying the surface charge transport properties by forming heterojunction of BiVO4 with other metal oxides layers having ultralow thickness is a promising route, as it may facilitate charge separation/transport without affecting other properties of BiVO4. In this study, the structural, optical and PEC properties of heterojunction of BiVO4 having ultrathin overlayers of Fe2O3, MoO3 and ZnO has been investigated. The electrochemical impedance (via electrochemical impedance spectra in PEC cell) and surface photovoltage (using KPFM) measurements indicates improved charge transport owing to staggered band alignment and favourable band bending in case of BiVO4/MoO3 heterojunction as compared to pristine BiVO4, BiVO4/Fe2O3 and BiVO4/ZnO heterojunctions. Enhanced photocurrent density in BiVO4/MoO3 of ~0.22 mA/cm2 at 1.23 VRHE which is 6 times as compared to pristine BiVO4 layers has been observed. The results of the present study show that by forming heterojunction with a suitable semiconductor material can be used to enhance the PEC response by modifying the surface charge transfer characteristics and there is a large possibility of using other semiconductor materials for further investigations and improvement. 相似文献