APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Zijun Sun,Zhen Li,Yi Kuang,Chunrong Su,Shuangwei Yu,Yujing Wang,Xiong He,Jinghua Liu
Severe charge recombination and poor surface water oxidation kinetics are key restrictions of BiVO 4 photoanode for efficient photoelectrochemical (PEC) water oxidation. In order to overcome this issue, we introduce Co@β-cyclodextrin (Co@β-CD) supramolecule as oxidation evolution catalyst (OEC) into BiVO 4 photoanode for the first time via a facile two-step immersion method. The optimal Co@β-CD/BiVO 4 photoanode displays a remarkable photocurrent density of 5.3 mA cm −2 at 1.23 V RHE , which is ca. 3.5 times as high as that of pristine BiVO 4 photoanode. Further analyses indicate that photogenerated holes could quickly transfer from BiVO 4 to Co sites through β-CD, thereby suppressing charge recombination. Moreover, due to the spatial confinement effect of β-CD, the dispersed Co sites in Co@β-CD are considered to possess the high catalytic activity in similar with single-atom catalyst, which accelerates the surface water oxidation kinetics. This work not only demonstrates the superiority of supramolecule/semiconductor composite photoanode, but also provides a facile preparation route for the large-scale preparation of high-performance photoanodes.
研究领域:
材料科学
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能源科学
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催化科学
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产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2021
·Vol. 8
·期 15
·3723-3732
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IF 6.569
Yuwei Zhang,Xiaoxiang Xu
Solid solutions of LaTaON2 and BaTaO2N, i.e., La1−xBaxTaO1+yN2−y (0 ≤ x, y ≤ 1), have been investigated as visible-light-active photocatalysts for water oxidation reactions. A number of important parameters such as Ta–O/N distance, Ta–O/N–Ta angle, band gap and band edge alignments can be tailored by adjusting their solid solution levels, which in turn, effectively steer the photocatalytic behaviors. In particular, optimal photocatalytic activity for water oxidation can be achieved in the solid solution La0.2Ba0.8TaO1+yN2−y (x = 0.8), exhibiting an apparent quantum efficiency (AQE) as high as 3.91% at 420 ± 20 nm. This work signifies the usefulness of the solid solution strategy for ameliorating the photocatalytic properties of perovskite oxynitrides that can be well-extended to many other semiconductor photocatalysts.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 20
·4640-4647
·
IF 5.773
Fangfang Wu,Xiaoqin Sun,Gang Liu,Xiaoxiang Xu
Despite a strong visible light absorption at a wavelength as far as 610 nm, SrTaO2N generally exhibits poor photocatalytic activity due to photocatalytic self-decomposition. In this study, we introduce Na into the B site of SrTaO2N and perform an investigation on its crystal structure, optical absorption and photocatalytic water oxidation in response to Na incorporation. Our results suggest that Na incorporation effectively enhances local Ta–O(N) bond strength, which is responsible for strong interband light absorption, low tendency to defect formation and high stability against photocatalytic self-decomposition. Efficient photocatalytic water oxidation was realized in Na-modified SrTaO2N (Sr0.8Na0.2TaO2.8N0.2) with an apparent quantum efficiency as high as 0.2% under visible light illumination (≥400 nm). This simple strategy highlights the benefits of alkaline metal modification and can be extended to other nitrides or oxynitrides where management of local bond strength is needed.
研究领域:
材料科学
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光化学
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能源转化
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表面化学
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无机化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Haolun Li,Mingxin Lyu,Yanhua Lai,Xingxing Cheng,Zhen Dong
Spinel oxides are widely used to enhance photoanodes’ photoelectrochemical (PEC) water oxidation performance. In this paper, we demonstrate that a p-type photothermal MnCo2O4 layer, inserted between BiVO4 and FeOOH cocatalysts, can significantly enhance PEC performance. On the one hand, the charge recombination is greatly suppressed since p-type MnCo2O4 can form a p–n heterojunction with n-type BiVO4. On the other hand, upon near-infrared (NIR) light irradiation, the deposited MnCo2O4 shows excellent photothermal conversion performance that can further facilitate charge transfer and accelerate the water oxidation process by elevating the operating temperature. In addition, the FeOOH cocatalyst is introduced to fully utilize the holes reaching the surface and further enhance the surface oxygen evolution kinetics. Consequently, the carefully constructed BiVO4/MnCo2O4/FeOOH photoanode shows excellent photocurrent (4.71 mA cm–2) at 1.23 V vs RHE (VRHE) and superior applied bias photon-to-current efficiency (1.62%) at 0.6 VRHE. The photocurrent density maintains more than 90% of the initial photocurrent after 4 h of combined solar and NIR light irradiation. Enhancing the PEC catalytic activity of photoelectrodes using photothermal materials is a simple and effective strategy, which can be used to explore PEC activity enhancement in other photoelectrodes.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
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2024
·
IF 14
Fengli Wei,Jinghao Shen,Jiayin Xie,Zuyang Luo,Luyan Shi,Tayirjan Taylor Isimjan,Xiulin Yang,Jieshan Qiu,Bin Wu
Understanding and manipulating the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity. Herein, we present a synthesis of NiSe 2 -Ce 2 (CO 3 ) 2 O heterostructure and demonstrate the efficacy of interfacial Ce 2 (CO 3 ) 2 O in promoting the formation of catalytically active centers to improve oxygen evolution activity. In-situ Raman spectroscopy shows that incorporation of Ce 2 (CO 3 ) 2 O into NiSe 2 causes a cathodic shift of the Ni 2+ →Ni 3+ transition potential. Operando electrochemical impedance spectroscopy reveals that strong electronic coupling at heterogeneous interface accelerates charge transfer process. Furthermore, density functional theory calculations suggest that actual catalytic active species of NiOOH transformed from NiSe 2 , which is coupled with Ce 2 (CO 3 ) 2 O, can optimize electronic structure and decrease the free energy barriers toward fast oxygen evolution reaction (OER) kinetics. Consequently, the resultant NiSe 2 -Ce 2 (CO 3 ) 2 O electrode exhibits remarkable electrocatalytic performance with low overpotentials (268/304 mV @ 50/100 mA cm −2 ) and excellent stability (50 mA cm −2 for 120 h) in the alkaline electrolyte. This work emphasizes the significance of modulating the dynamic changes in developing efficient electrocatalyst.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2018
·
IF 3.886
Lipeng Wan,Feng-Qiang Xiong,Bingxue Zhang,Ruxin Che,Yue Li,Minghui Yang
LaNbON 2 has narrow bandgap and wide visible-light absorption band, yet no photocatalytic water oxidation on LaNbON 2 has been reported. By a post-annealing treatment in Ar, anion vacancies were brought into LaNbON 2 as shown by EPR spectroscopy. These could act as donors in the semiconductor. And consequently the oxidative power of holes was enhanced as indicated by the difference between fermi level and valence band maximum ( E F - E VBM ) evaluated from valence band XPS . The annealed LaNbON 2 photocatalyst acquired water oxidation ability for the first time, which was improved by combining CoO x as cocatalyst . Annealed LaNbON 2 derived from La 3 NbO 7 had smaller particle size, higher concentration of anion vacancies, bigger E F - E VBM and better performance for photocatalytic oxygen evolution reaction than LaNbON 2 derived from LaNbO 4 .
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Liang Yan,Bing Zhang,Zhonggang Liu,Junlu Zhu
The development of highly active and low-cost oxygen evolution reaction (OER) electrocatalysts is pivotal for the efficient generation of renewable hydrogen but still challenging. Heteroatom doping and oxygen vacancy (Ov) engineering are effective strategies to regulate the physical and chemical properties of the catalysts and thus facilitating the intermediates absorption/desorption. Herein, the rational design of Cu doping CoOOH porous nanoplates with rich Ov grown on carbon fiber paper (Cu-CoOOH/CFP) is performed to enhance the OER performance. Experiment results and density functional theory (DFT) calculations uncovered that the synergistic effect of Cu doping with Ov exceptionally modulated the electronic structure of Cu-CoOOH/CFP so that enormously facilitates the (O–H)* bond cleavage and optimize the Gibbs free energies of OER intermediates, thus contributing to fast kinetics and outstanding OER activity. As expected, the optimized three-dimensional (3D) self-supported Cu-CoOOH/CFP with unique porous structure shows unprecedented OER activity with a low overpotential of 234 mV to attain a current density of 10 mA cm −2 , as well as superior stability in 1.0 M KOH. This work provides an effective electronic engineering approach for the rational design of nonprecious-metal and efficient electrocatalysts for water oxidation and beyond.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 10
·期 1
·263-267
·
IF 5.726
Gang Yuan,Yujie Hu,Zihan Wang,Qiwei Wang,Li Wang,Xiangwen Zhang,Qingfa Wang
Water oxidation plays a pivotal role in energy conversion and storage such as in water splitting and metal-air batteries. The development of a highly active and stable electrode for water oxidation at a low price is greatly challenging. Here, we report a self-supported oxygen evolution reaction (OER) electrode with a 3D porous Ni foam (NF) as a core and a dense layer of amorphous phosphorus-doped Ni hydroxide (Ni–OH/P) film as a shell. This facilely fabricated 3D core–shell structured electrode with directly grown active materials offered improved activity and prolonged stability for OER. It required an overpotential of 490 mV to deliver a current density of 100 mA cm−2; it showed a small Tafel slope at 87 mV dec−1 and sustained elongated electrolysis at 100 mA cm−2 for 100 h. The NiOOH shell was in situ formed on the surface of the Ni–OH/P film. Then, a new core–shell structured film was constructed. The synergetic effects of the newly formed crystalline NiOOH shell and amorphous Ni–OH/P core contributed to high stability under harsh conditions. This work presents a facile and easy scale-up path to develop self-supported hybrid electrodes for efficient and stable energy conversion and storage.
研究领域:
能源材料
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2023
·
IF 12.9
Guoquan Liu,Yong Zhu,Hua Gao,Suxian Xu,Zhibing Wen,Licheng Sun,Fei Li
Developing efficient photocatalysts for water oxidation is among the central challenges of solar energy conversion. Here, we report semiconductor–molecular photocatalysts by integration of heteronuclear bimetallic polyphthalocyanine (PPc) catalysts with particulate bismuth vanadate (BiVO4) as the photosensitizer. Their photocatalytic activity for water oxidation was modulated by tuning the Fe/Co ratio of polyphthalocyanines. At an optimal Fe/Co ratio of 3:1, the resulting Fe3CoPPc-BiVO4 hybrid exhibits an excellent oxygen evolution rate of 4557 μmol g–1 h–1 in the presence of iodate under visible light irradiation, which is nearly two orders of magnitude greater than that of pristine BiVO4 and superior to those of the corresponding homometallic counterparts. Both experimental and theoretical methods suggest that the presence of a large population of high-valent Fe/Co molecular species due to the favorable interfacial charge transfer and upshift of the d-band centers of metal sites toward Fermi level lead to a lower energy barrier for the O–O bond formation and eventually promote the oxidation of water.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Zi-Han Zhang,Tao Yang,Ze-Yuan Wang,Hai-Chao Wang,Xin-Zheng Yue,Sha-Sha Yi
The photoelectrochemical (PEC) performance of hematite ( α -Fe 2 O 3 )-based photoanodes is still far from its theoretical value because they are constrained by serious charge recombination and sluggish water oxidation kinetics. Herein, we developed a heterostructural photoanode by coating boron doped graphite carbon nitride nanolayers onto an Fe 2 O 3 nanoarray (BCN/Fe 2 O 3 ), followed by modification with NiCo(OH) x cocatalyst. The constructed NiCo(OH) x /BCN/Fe 2 O 3 demonstrates a significantly improved photocurrent density of 2.7 mA cm −2 at 1.23 V RHE (V versus reversible hydrogen electrode), which is 3.2 times higher than that of pristine Fe 2 O 3 . Additionally, it exhibits an extremely negative onset potential of 0.60 V RHE . Detailed studies reveal that the BCN/Fe 2 O 3 heterojunction endows a driving force for charge separation and establishes a direct pathway for their transport, while NiCo(OH) x acts as a cocatalyst to accelerate the surface water oxidation reaction.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Yuli Xiong,Lin Yang,Huichao He,Jing Wan,Peng Xiao,Wenlong Guo
The successive ionic layer absorption and reaction (SILAR) method has been successfully used for the thin film preparation of metal oxides. In this work, we firstly fabricate the hybrid Bi 2 MoO 6 @Bi 2 Mo 2 O 9 photoanode by a one-step SILAR method. The optimized Bi 2 MoO 6 @Bi 2 Mo 2 O 9 demonstrates a photocurrent about 0.160 mA cm −2 at 1.23 V vs. RHE, which is 3.6 and 8.0 times enhancement compared with pristine Bi 2 MoO 6 and Bi 2 Mo 2 O 9 for water oxidation . The enhanced efficiencies of charge separation and oxidation kinetics by Bi 2 MoO 6 @Bi 2 Mo 2 O 9 are 20.5% and 54.6% at 1.23 V vs. RHE, which is higher than Bi 2 Mo 2 O 9 (9.2% and 15.4%) and Bi 2 MoO 6 (10.7% and 29.2%). Moreover, the electron transport time of Bi 2 MoO 6 @Bi 2 Mo 2 O 9 is 0.038 ms at 300 W m −2 through the controlled intensity modulated photocurrent spectrometer analysis, which is lower than Bi 2 Mo 2 O 9 (0.087 ms) and Bi 2 MoO 6 (0.052 ms). The enhanced photoelectrochemical activities of Bi 2 MoO 6 @Bi 2 Mo 2 O 9 can be attributed to the matched energy band between Bi 2 Mo 2 O 9 and Bi 2 MoO 6 , which could not only improve the charge separation, but also accelerate the charge migration. Therefore, our research indicates an effective technique for fabricating Bi 2 MoO 6 @Bi 2 Mo 2 O 9 by one step process, and thus may provide a new idea for the preparation of other hybrid ternary metal oxides.
研究领域:
材料科学
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Shuo Li,Yahui Li,Juan Zhang,Xiutao Liu,Kaixin Zhang,Yu Zhang,Xi-ming Song
A CoOOH cocatalyst overlayer is electrochemically deposited on the BiVO 4 surface, and thermal annealing converted CoOOH to Co 3 O 4 in situ. The primary difference between the two cocatalysts lies in their electrolyte permeabilities, resulting in significant differences in their thermodynamic effects on enhancing the photoelectrochemical water oxidation performance. We proved that the CoOOH cocatalyst is unable to achieve true chemical passivation of the surface states of the BiVO 4 photoanode, whereas the Co 3 O 4 cocatalyst can chemically passivate the surface states. Nevertheless, the CoOOH cocatalyst still exhibits better water oxidation performance than Co 3 O 4 , which is attributed to the fact that the permeable CoOOH cocatalyst can accumulate more photogenerated holes in the bulk phase and provide more active sites. However, the CoOOH cocatalyst still exhibits better water oxidation performance compared to Co 3 O 4 , which is attributed to the permeable CoOOH cocatalyst can accumulate more photogenerated holes in its bulk phase and offer more active sites.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）