INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
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IF 4.2
Haihong Wang,Huiyan Ma,Yan Li,Lin Cheng,Jucai Yang,Juming Liu
Efficient, low-cost, and easily scalable wide-spectral-responsive TiO2 photocatalysts are still extremely desired in driving photocatalytic degradation toward practical applications. In this work, a modified TiO2 with a narrow band gap and low valence band (VB) (CC-OV-TiO2) was successfully synthesized based on a facile sol–gel and low-temperature carbonization process, which can be used for the photocatalytic degradation and mineralization of a wide range of phenols. The results show that the interstitial doping of carbonates and the modification of surface oxygen vacancy (OV) defects together contribute to the formation of the VB tail states, which substantially narrow the band gap of TiO2 and widen the photoresponse range. Meanwhile, the carboxylated carbon species induce a substantial downward shift of the VB edge through coordination of the electron-withdrawing carboxyl groups, which further enhances the oxidation ability of the photogenerated holes. Accordingly, CC-OV-TiO2 with a narrow band gap and low VB exhibits superior and stable photocatalytic performance.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2022
·
IF 4.644
Yuewen Li,Yu Zhang,Xing Hou,Chunkun Lin,Degang Bu,Yalin Lan,Na Li,Shuyao Wu,Shuo Li,Xi-Ming Song
Seeking novel solar energy utilization and conversion methods has always been a frontier topic in energy research. Here, we propose a new way to directly photoelectrodeposit metals using solar energy based on semiconductor energy band theory . Three kinds of semiconductor photoanodes (TiO 2 , BiVO 4 and Fe 2 O 3 ) are employed to deposit metallic Cu or Bi at the cathode under illumination without external voltage. It is found that when TiO 2 and BiVO 4 are used as photoanodes, Cu, Cu 2 O and Bi can be continuously deposited on the cathode, but when Fe 2 O 3 photoanode is irradiated, no material comes out. The results prove that the potential of electrons in the conduction band determines whether photoelectric deposition occurs or not. The related mechanism involves the oxygen reduction reaction (OER) of the valence band holes of the photoanode, the collection of conduction band electrons by back electrode, as well as the reduction of metal ions on the counter electrode. In addition, we also put forward the concept of using the deposited Cu or Bi as the metal electrode to form a new metal-air battery to release chemical energy of the deposited metal.
研究领域:
材料科学
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能源研究
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产品关联
DOI
高影响因子
Journal of Saudi Chemical Society
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2015
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IF 2.523
Lijie Wang,Xi Zhang,Peng Zhang,Zetan Cao,Junhua Hu
Mn doped TiO 2 was synthesized by hydrothermal treatment of titanium boride and manganese chloride. The doped nano powders were fabricated by adding ammonium water into the mother solution which was obtained hydrothermally. The calcination of precursory powders took place at the temperature of 400–600 °C which resulted in the formation of anatase with a small amount of rutile phase. The shift of valence band maximum (VBM) toward the lower binding energies was observed by measuring the position of VBM with reference to the Fermi level, which contributed to the significant red-shift of absorption edges. X-ray photoelectron spectroscopy (XPS) measurement shows that manganese exists in both 4+ and 3+ valance states, which may have a temperate replacing of Ti 4+ because of the charge compensation compared with 2+ and 3+ valence states. The property of photoelectric conversion was detected by evaluating the photocurrent under visible light (>420 nm), and the fluorescence spectra also proved that 6%-Mn doped TiO 2 (DM6) shows a better photoelectric conversion performance.
研究领域:
材料科学
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光催化
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 21
·5562-5571
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IF 7.779
Fudong Zhang,Xia Qi,Mingkai He,Fengshan Zheng,Lei Jin,Zhanhui Peng,Xiaolian Chao,Zupei Yang,Di Wu
Previous studies have revealed that both Bi doping and Bi2Te3 alloying are successful strategies to optimize the thermoelectric performance of SnTe; however, detailed and thorough investigations on exactly how they differ in modulating the band structure and microstructure were seldom given. Through a systematic comparison between Bi-doped and Bi2Te3-alloyed SnTe, we find in this work that despite the fact that they both contribute to the valence band convergence of SnTe, Bi2Te3 alloying induces little effect on the hole concentration unlike the typical n-type feature of Bi-doping; moreover, Bi2Te3 alloying tends to produce dense dislocation arrays at micron-scale grain boundaries which differs significantly from the substitutional point defect character upon Bi-doping. It was then found that Bi2Te3 alloying exhibits a relatively higher quality factor (B ∼ μw/κlat) at higher temperatures than Bi-doping. Subsequent Ge-doping in Bi2Te3-alloyed samples results in further valence band convergence and hole concentration optimization and eventually results in a maximum figure of merit ZT of 1.4 at 873 K in the composition of (Sn0.88Ge0.12Te)0.97-(BiTe1.5)0.03.
研究领域:
材料科学
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热电材料
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Jie-hao Li,Jie Ren,Ying-juan Hao,Er-peng Zhou,Yue Wang,Xiao-jing Wang,Ran Su,Ying Liu,Xue-han Qi,Fa-tang Li
Constructing heterojunctions would result in the change of valence band position, which is an important factor determining the oxidative ability of photo-induced holes, has received scant attention. In this paper, β-Bi 2 O 3 /Bi 2 O 2 CO 3 composites with different ratios were obtained via ionic-liquid-assisted solvothermal and in-situ calcination processes. UV–vis DRS, Mott-Schottky test, and Kelvin probe measurement showed the change of band gaps of β-Bi 2 O 3 and Bi 2 O 2 CO 3 before and after heterojunction formation. SPV, ESR, photocurrent, and scavenger experiments identified the separation efficiency of photo-generated electrons and holes, as well as the active species generated in the photocatalytic process. The photocatalytic mechanism was investigated by the degradation of Rhodamine B (RhB) upon visible-light and simulated sunlight, respectively. The results demonstrated that β-Bi 2 O 3 /Bi 2 O 2 CO 3 heterojunctions possessed enhanced separation efficiency and higher degradation ability than the individuals under visible-light irradiation due to effective electron transfer. However, lower performance under simulated sunlight was observed, although their separation efficiency remained high. The decisive reason for this was that the up-shift of valence band of Bi 2 O 2 CO 3 induced by hybridization and the transition of holes from VB of Bi 2 O 2 CO 3 to that of β-Bi 2 O 3 with more negative potential decreased the oxidative ability of holes, which surpassed the positive influence of enhanced separation efficiency.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
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IF 2.567
Fan Tian,Huiping Zhao,Zan Dai,Gang Cheng,Rong Chen
Cl-incorporated BiOI nanostructures with different Cl/I molar ratios have been successfully fabricated via a facile room-temperature method in H2O/EG mixture solvent. Combined with FT-IR, Raman spectrum, XRD Rietveld refinements, and DFT calculation, the incorporated Cl ions are found mainly occupied on I sites, resulting in a hybrid valence band consisting of I 5p, O 2p, and Cl 3p orbitals, which deepens the valence band location of the materials and induces photogenerated holes with higher oxidation power. The incorporated Cl ions into the lattice also change the evolution of photogenerated electrons and holes, inducing the broadening of the bandgap but efficient production of photogenerated carriers. The enhanced oxidation power of Cl-incorporated BiOI products was evaluated by photocatalysis degradation of methylene blue, an organic dye for which pure BiOI shows negligible direct oxidation efficiency. Ascribed to the relatively low valence band maximum (VBM) and efficient generation of photoinduced electrons and holes, the incorporated products show distinct enhancement photocatalytic activities.
研究领域:
材料科学
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环境科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2017
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IF 3.582
Ting Song,Piyong Zhang,Jian Zeng,Tingting Wang,Atif Ali,Heping Zeng
Metal-organic framework (MOF) materials with their synthetic tunability and structural regularity offer an interesting platform to achieve photocatalytic H 2 production. To determine whether metal ions in MOF materials affect the photocatalytic hydrogen (H 2 ) evolution activity, very few studies investigated MOF materials having the same crystal structures and ligands. In this study, we describe the synthesis of isostructural MOF materials. Cadmium (II) or copper (II) were linked with the 4′-(2,4-disulfophenyl)-3,2′:6′,3″-terpyridine (H 2 DSPTP) organic ligand to form Cd-MOFs and Cu-MOFs, respectively. Although Cd-MOFs and Cu-MOFs had the same valence band (VB) energy, the conduction band (CB) level of Cu-MOFs was more negative than that of Cd-MOFs. Therefore, the reduction ability of Cu-MOFs was greater than that of Cd-MOFs. Moreover, Cu-MOFs showed excellent absorption of visible and even near-infrared (NIR) radiation, because it has strong metal-to-ligand charge transfer (MLCT) character. Interestingly, the rate of photocatalytic H 2 generation was 18.96 μmol h −1 in the presence of Cu-MOFs, which were irradiated with NIR light ; however, Cd-MOFs did not report any such activity. Moreover, the performance and stability of Cd-MOFs were different from that of Cu-MOFs. In this study, the proof of knowledge for rational photocatalyst design introduced here furnishs the notional framework for constructing high-activity MOF materials.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
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IF 9.446
Jian-guo Guo,Ying Liu,Ying-juan Hao,Yi-lei Li,Xiao-jing Wang,Rui-hong Liu,Fa-tang Li
Heterostructured Bi 3 O 4 Br/α-Bi 2 O 3 nanocomposites are prepared via in situ one-step self-combustion of ionic liquids. Tetrabutylammonium bromide (TBAB) is employed to be fuel, complexing agent for ionic liquids, as well as the reactant supplying Br for the objective material. The ratio of Bi 3 O 4 Br/α-Bi 2 O 3 can be easily adjusted by controlling the amount of TBAB. The heterojunctions show higher photocatalytic ability towards both azo dye methyl orange (MO) and colorless pollutant phenol . The electron spin resonance (ESR) test and p-nitro blue tetrazolium chloride (NBT) degradation result indicate that generation amounts of superoxide anion radicals ( O 2 − ) over heterojunctions are less than that over pure Bi 3 O 4 Br. Photoelectrochemical measurements show that separation efficiencies of photo-generated electrons and holes are decreased after the combination of Bi 3 O 4 Br and α-Bi 2 O 3 . Work function test and scavenger experiments display that holes play key role for pollutant degradation and the position of holes on α-Bi 2 O 3 is lowered via hybridization. Thus, the enhanced photocatalytic activity over composites can be attributed to the position decline of α-Bi 2 O 3 valence band, thus improving the reactivity of holes in direct oxidation of pollutants. In this case, valence band position is confirmed to be more important than separation efficiency of charge carriers in affecting photocatalytic performance.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 153
·期 4
·1109-1119
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IF 2.936
Ren Yanrong,Pu Hongzheng,Zeng Hanlu,Deng Chaofang,Yin Fengling,Wu Ya,Yang Dingfeng,Li Yuanyuan
Modulating the band edge position of a photocatalyst is important in photocatalysis. In this study, a more positive valence band position was realized by doping Sb in Li 2 SnO 3 . The downshifted valence band position was mainly attributed to the relatively low Sb energy level resulting from its higher electronegativity. Such band structure modification resulted in a stronger photo-oxidative capability for photogenerated holes (h + ), leading to an enhanced photodegradation rate toward tetracycline (TC) solution. For Li 2 Sn 0.9 Sb 0.1 O 3 , the efficiency reached 74% within 30 min, which was approximately 2.5 times that of Li 2 SnO 3 . Radical trapping experiments showed that h + played the dominant role in the photodegradation process. Finally, the photodegradation pathway was analyzed using liquid chromatography–mass spectrometry (LC–MS). These results might provide important insight for designing photocatalysts with high efficiency through band structure modification. Graphical Abstract
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2021
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IF 9.229
Xiao Xu,Juan Cui,Liangwei Fu,Yi Huang,Yong Yu,Yi Zhou,Di Wu,Jiaqing He
SnTe is deemed a promising mid-temperature thermoelectric material for low toxicity, low cost, and decent performance. Sole doping/alloying on Sn sites was reported to result in either modified band alignment or reduced lattice thermal conductivity, thus contributing to an enhanced overall thermoelectric figure of merit. However, this strategy alone is always unable to take full use of the material’s advantage, especially considering that it simultaneously pushes the hole concentration off the optimal range. In this work, we adopted a two-step approach to optimize the thermoelectric performance of SnTe in order to overcome the limitation. First, Mn was alloyed into Sn sites to increase the density of state effective mass of SnTe by regulating the valence bands; the Fermi level was further regulated by iodine doping, guided by a refined two-band model. Additionally, the lattice thermal conductivity was also suppressed by the microstructure optimizing via Mn doping and additional phonon scattering at ITe mass/strain fluctuation. As a result, a high ZT of 1.4 at 873 K was achieved for Sn0.91Mn0.09Te0.99I0.01. This study provides a way to refine the single doping stratagem used in other thermoelectric materials.
研究领域:
材料科学
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热电材料优化
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Shu Wang,Xin Li,Yuan Chen,Wenlong Yang,Shuang Han,Hui Zhang
The artificial-photosynthesized S-scheme heterojunction for photochemical energy conversion has inspired promising implications for green environmental remediation. Herein, we develop a visible-light response Sn-CdS/ZnFe 2 O 4 heterostructure to exhibit efficient photo-Fenton functionalities on the degradation of dye RhB and antibiotic TC under the simulated solar-driven irradiation. In our work, s-p orbital hybridization by Sn-doping has been employed as an effective strategy to reconstruct a new valence band to further modify the sulfides for their long-term stabilities in strong oxidizing environment. We have not only calculated the rationality of doping model and heterostructure but also experimentally verified the photo-physical process of charge transfer. Furthermore, the modified photocatalyst is conducive to contribute to the rapid and sustainable Fenton-like reactions with the best RhB and TC degradation rates of 1.00 μmol·min −1 ·g −1 cat. and 11.26 μmol·min −1 ·g −1 cat. respectively, which synergistically interplays with the generation and transition of reactive oxygen free radicals. This work extends a new viewpoint for the transition metal doping territory of electronic structure optimization to achieve pollutant degradation with high activity and stability to favor water decontamination applications.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 14
·3578-3589
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IF 7.779
Jie-hao Lia,Rui-hong Liu,Meng Ning,Yi-lei Li,Ying Liu,Xinying Liu,Phathutshedzo Khangale,Diane Hildebrandt,Xiao-jing Wang,Fa-tang Li
Constructing heterostructured photocatalysts will generally improve the separation efficiency of photo-induced carriers; however, the change in the energy band position that affects their redox ability has received little attention. In this work, α-Bi2O3/Bi5NO3O7 heterojunctions are prepared via solution combustion synthesis and characterized by UV-vis DRS, Mott–Schottky and Kelvin probes, and the band structures of α-Bi2O3 and Bi5NO3O7 before and after the formation of the heterojunction are obtained. The results of the degradation of rhodamine B and tetracycline indicate that the main active species are holes and superoxide anion radicals, respectively. Although separation efficiency over heterojunctions is higher than that over individual Bi5NO3O7 and α-Bi2O3, lower degradation ability is observed. The reason is that the heterojunction formation causes an upward shift of the valence band of Bi5NO3O7 and a downward shift of the conduction band of α-Bi2O3, which reduces the oxidation ability of holes and the ability to activate molecular oxygen, respectively. The decrease in the redox ability outweighs the positive impact of enhanced separation efficiency.
研究领域:
材料科学
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环境科学
✓ 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）