Catalysis Science & Technology
·
2020
·Vol. 10
·期 11
·3709-3719
·
IF 5.721
Chengwei Qiu,Jinjin Lin,Jinni Shen,Dan Liu,Zizhong Zhang,Huaxiang Lin,Xuxu Wang
Anatase/rutile TiO2 heterophase junction composites have been documented to have much higher photocatalytic activity than single phase TiO2 (nude anatase or nude rutile) for various chemical reactions, including hydrogen production from methanol–water solution and pollution degradation. Further improving the photocatalytic performance of heterophase junction photocatalysts is a subject worth studying in both theory and practice. Based on the concept of junction interface regulation and our previous findings, we embedded Ni12P5 nanoparticles at the interface between anatase (A) and rutile (R) TiO2 by a multi-step preparation method to obtain an A/Ni12P5/R composite with a sandwich-like structure. It was found that loading Ni12P5 on the outside surface of anatase TiO2 (Ni12P5/A), rutile TiO2 (Ni12P5/R), P25 TiO2 (Ni12P5/P25), and A/R composite (Ni12P5/A/R) leads to a decrease in the photocatalytic activity; however, interestingly, the A/Ni12P5/R sample showed higher photocatalytic activity than the other samples of loaded or unloaded Ni12P5, although the loaded Ni12P5 in the latter case is inaccessible to the reactant molecules. This abnormal phenomenon can be attributed to two main reasons. (i) Ni12P5 as a metal-like material has a higher work function than anatase and rutile, which leads to the formation of Schottky junctions at the interface between the two intimately contacted phases. (ii) When Ni12P5 is located on the outside surface, the Schottky junction is unfavorable for the transfer of photogenerated electrons from TiO2 to Ni12P5. However, when Ni12P5 is sandwiched between A and R, the formation of a reverse tandem Schottky junction can facilitate the directed transfer of photogenerated electrons from R phase to A phase. This work again verifies that photocatalytic activity can be regulated and controlled by introducing metal and metal-like particles within the junction of a metal/semiconductor interface or even on a semiconductor/semiconductor interface. Our findings not only provide a novel usage of Ni12P5 as a co-photocatalyst but also deepens the understanding of the Schottky effect on the photocatalytic process.
研究领域:
材料科学
·
光催化
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2025
·Vol. 155
·期 2
·1-17
·
IF 2.4
Gan Wei,Guo Yan,Zhu Dan,Ling Min,Jiang Can,Zhang Shengfu
With the increasing problems caused by water pollution, the use of photocatalytic oxidation to remove pollutants from wastewater is a sustainable strategy. However, it is challenging to develop well-designed photocatalysts with high photo-quantum efficiency and the comprehension of their photocatalytic reaction mechanisms. Herein, a R/A-TiO 2 /Ti 3 C 2 T x (R: rutile; A: anatase) photocatalyst with different ratios of rutile and anatase phases was prepared by a facile hydrothermal method. The results showed that the number of rutile and anatase phases could be readily regulated by adjusting the dosage of titanium isopropoxide (TTIP) and Ti 3 C 2 T x . The prepared R/A-TiO 2 /Ti 3 C 2 T x -0.2 contained a mass fraction of 42% rutile phase and 58% anatase phase, with the interface between the two phases exhibited a tightly bonded structure. Meanwhile, the heterojunction between the heterophase TiO 2 and Ti 3 C 2 T x interfaces improved the photo-quantum efficiency of R/A-TiO 2 /Ti 3 C 2 T x , and the degradation efficiency of Rhodamine B (RhB) by R/A-TiO 2 /Ti 3 C 2 T x -0.2 was 77.82% in 2 h under ultraviolet light illumination. Ultimately, the active species capture experiments verified that the primary active species in the photocatalytic reaction was h + , ·OH, and·O 2 − . This work could shed light on the new approach to the rational design of high-efficiency heterophase TiO 2 -based photocatalysts. Graphical R/A-TiO 2 /Ti 3 C 2 T x photocatalysts with heterojunctions were controllably synthesized by an EDTA-2Na-assisted hydrothermal method.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Xiaoxue Ke,Changcun Tang,Renzhi Xiong,Yanhe Xiao,Baochang Cheng,Shuijin Lei
It is an important strategy to design composite materials with a special microstructure and a tunable electronic structure through structural compatibility. In this work, a novel hexagonal/cubic ZnIn2S4 polymorphic heterophase junction with a three-dimensional multihierarchical structure is successfully constructed by in situ growth of hexagonal ZnIn2S4 nanosheets on the surface of cubic ZnIn2S4 flower-like microspheres prepared by topological chemical synthesis. On the one hand, the multihierarchical architecture provides large specific surface area, abundant active sites, and excellent light trapping capability. On the other hand, the construction of a direct S-scheme heterophase junction enables the formation of a special charge-transfer channel under the force of a built-in electric field, which not only improves the separation efficiency of carriers but also ensures the stronger reaction activity of charges. The prepared ZnIn2S4 heterophase junction composite photocatalyst exhibits greatly boosted photocatalytic efficiency in rhodamine B degradation, hexavalent chromium reduction, and water splitting for hydrogen production, which are 12.3, 6.5, and 3.1 times higher than that of pure hexagonal ZnIn2S4 and 8.1, 5.1, and 2.3 times higher than that of pure cubic ZnIn2S4, respectively, demonstrating its significant potential for applications in energy and environmental fields.
研究领域:
材料科学
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环境科学
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能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER INTERNATIONAL
·
2018
·Vol. 67
·期 9
·1221-1228
·
IF 2.352
Meng Ma,Kai Liu,Haiming Zheng,Si Chen,Bozhen Wu,Yanqin Shi,Xu Wang
Poly( l -lactic acid)/crosslinked polyurethane (PLLA/CPU) blends which were prepared via reactive blending of PLLA with poly( ϵ -caprolactone) (PCL), glycerol and 4,4′-methylenediphenyl diisocyanate showed excellent toughness. The effects of the composition of the mixture and degree of crosslinking of CPU on the toughness of the PLLA/CPU blends (80/20 w/w) were studied in detail. Dynamic mechanical analysis and rheological measurements were used to characterize the structure of the in situ formed CPU in the PLLA matrix. A novel netlike phase structure was observed when the average molecular weight of PCL and degree of crosslinking were 1 kDa and 10%, respectively. The impact strength of the blend was enhanced from 2.2 kJ m −2 for pure PLLA to 62.4 kJ m −2 ; meanwhile, the elongation at break was increased to 489.8%. Therefore, the mechanical properties of PLLA/CPU blends can be easily tailored by tuning the composition of the mixture and the degree of crosslinking of CPU. © 2018 Society of Chemical Industry
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
Crystals
·
2020
·Vol. 10
·期 5
·367
·
IF 2.404
Xiaoyi Gao,Nannan Dong,Fangquan Xia,Qinghu Guo,Hua Hao,Hanxing Liu,Shujun Zhang
The impact of phase structure on piezoelectric performances of <001> textured Na0.5Bi0.5TiO3(NBT) based lead-free ceramics was studied, including 0.88NBT-0.08K0.5Bi0.5TiO3-0.04BaTiO3(88NBT) with morphotropic phase boundary (MPB) composition and 0.90NBT-0.07K0.5Bi0.5TiO3-0.03BaTiO3(90NBT) with rhombohedral phase. Both textured ceramics exhibit a high Lotgering factor, being on the order of f~96%. The piezoelectric coefficients of the textured 88NBT and 90NBT ceramics are increased by 20% and 60%, respectively, comparing to their randomly oriented ceramics. The piezoelectric enhancement of 90NBT textured ceramic is three times higher than 88NBT, revealing the phase structure plays a significant role in enhancing the piezoelectric performances of textured ceramics. Of particular significance is that the 90NBT textured ceramic exhibits almost hysteresis-free strain behavior. The enhanced piezoelectric property with minimal strain hysteresis is attributed to the <001> poled rhombohedral engineered domain configuration.Keywords:textured ceramics;phase structure;rayleigh analysis;strain behavior
研究领域:
材料科学
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物理学
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产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2022
·
IF 6.959
Xiaoshuang Kang,Guohui Dong,Tingting Dong
In this study, TiO2 samples are synthesized through two stages including hydrolysis and calcination. It is found that the addition of HCl in the hydrolysis stage could facilitate the formation of heterophase junction TiO2. By annealing at 300 °C in an argon atmosphere, interfacial oxygen vacancies (Vo) and surface Vo (distributed in the anatase phase) can be constructed in the heterophase junction TiO2. After photocatalytic experiments, it can be found that surface Vo and interface Vo have a synergistic effect in the production of photocatalytic reactive oxygen species (ROSs). Surface Vo can enrich O2 and transmit electrons to O2 on the surface of anatase. Therefore, the enriched O2 can be converted into •O2– and 1O2 easily. The interfacial Vo not only facilitate the electron transmission between the two phases but also change the electron transfer mode from I-scheme to Z-scheme. Thus, interfacial Vo make photogenerated electrons transfer to anatase and photogenerated holes leave in the rutile. These holes in the rutile part have high oxidation potential and can better oxidize H2O (or OH–) molecules to •OH. They can also oxidize •O2– to 1O2. This work promotes the further development of defect design and application in photocatalytic materials.
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
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2022
·Vol. 33
·期 26
·20981-20991
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IF 2.779
Yan Gui-wei,Liu Qing-qing,Fang Bi-jun,Chen Zhi-hui
Mg doped (Ba 0.98 Li 0.02 )TiO 3 energy storage ceramics with antiferroelectric-like double hysteresis loops were prepared using solid-state reaction method. XRD patterns indicated that tetragonal phase structure of the pure (Ba 0.98 Li 0.02 )TiO 3 ceramic was destroyed and the orthorhombic phase structure appeared with Mg doping. The ratio of orthorhombic/tetragonal phase increased with Mg content increasing, and the value of polarization was in direct proportion to the ratio of orthorhombic/tetragonal phase. The breakdown strength of (Ba 0.98 Li 0.02 )(Mg x Ti 1− x )O 3 ceramics was improved from 60.97 kV/cm at x = 0 to 103.66 kV/cm at x = 0.04. The optimum energy storage properties of (Ba 0.98 Li 0.02 )(Mg x Ti 1− x )O 3 ceramics were obtained with energy storage density of 0.76 J/cm 3 at 102.5 kV/cm when x = 0.04, which is nearly 2.3 times larger than the pure (Ba 0.98 Li 0.02 )TiO 3 ceramic, and the energy storage efficiency was improved from 64 to 87%.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2020
·Vol. 31
·期 12
·9167-9175
·
IF 2.22
Cai Wei,Zhang Qianwei,Zhou Chuang,Gao Rongli,Zhang Shilong,Li Zhendong,Xu Ruicheng,Chen Gang,Deng Xiaoling,Wang Zhenhua,Fu Chunlin
Ba 0.85 Ca 0.15 Zr 0.9 Ti 0.1 O 3 (BCZT) ceramics with various grain sizes were fabricated through solid-state method followed by different sintering temperatures. The influences of grain size and phase structure on the electric properties and energy storage performance were systematically investigated. The remnant polarization and quasi-static piezoelectric constant of BCZT samples increase gradually as grain size increases, and the samples with the grain size of 44.37 µm exhibit excellent ferroelectricity and piezoelectricity (2 P r = 25.4 µC/cm 2 , d 33 = 513 pC/N). Although the energy storage density of BCZT samples with the grain size of 8.28–44.37 µm is relative lower, all the ceramic samples have higher energy storage efficiency (82–87.4%). There is the maximum energy storage density in phase transition temperature of tetragonal–cubic phase for all BCZT ceramics and the maximum energy storage density first increases and then decreases with the increase of grain size. But the energy storage density of BCZT ceramics near room temperature decreases with increasing of grain size. The smaller grain size is beneficial to improve the room temperature energy storage density of BCZT samples and is disadvantageous to obtaining superior ferroelectric and piezoelectric properties.
研究领域:
材料科学
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物理学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2012
·
IF 1.751
Lin Gan,Zhi-Yong Mao,Yu-Qiang Zhang,Fang-Fang Xu,Ying-Chun Zhu,Xue-Jian Liu
Ce 3+ -doped β-SiAlON blue phosphors with composition of Ce x Si 6− z Al z O z N 8− z (0.2≤ z ≤4) at a fixed x =0.01 were synthesized by the gas pressure sintering method. The phases and photoluminescence properties were found to be directly correlated to the z value. Higher z value would result in the formation of AlN polytypoid impurity phases. The optimal z value resides in the range 0.3≤ z ≤0.5, by which high purity of β-SiAlON phase, good crystallinity and fine grain size were obtained, leading to the best luminescence properties. These phosphors could be a good candidate for application in white light-emitting diodes using InGaN-based near–ultraviolet chips.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2019
·
IF 7.723
Jinjin Lin,Tao Sun,Minbo Li,Jinxiang Yang,Jinni Shen,Zizhong Zhang,Ying Wang,Xiaoyan Zhang,Xuxu Wang
Loading noble metal on the surface has been widely used to improve photocatalytic activity of semiconductor photocatalyst. Here, Pt-embedded anatase (A)-rutile (R) TiO 2 junction photocatalyst (A/Pt/R) was found to show much more efficient photocatalytic H 2 evolution activity than the other TiO 2 photocatalysts loading Pt on the outside surface (such as Pt/A/R, Pt/A, Pt/R and Pt/P25), although the as-embedded Pt is unreachable to reactants. The A/Pt/R sample shows a photocatalytic H 2 evolution rate as high as 17.9 mmol⋅g cat −1 ⋅h −1 , which is 27.2 and 2.5 times higher than the common A/R and Pt/A/R samples, respectively. The traditional theory fails to explain the unexpected high photoactivity. The reverse tandem Schottky junction is suggested to be possibly responsible for the high photoactivity of A/Pt/R, which allows the photogenerated electrons to transfer more swimmingly from rutile to anatase than the common A/R phasejunction. This finding provides a new strategy for further promoting photocatalytic activity of Pt/TiO 2 and other heterophase or heterojunction photocatalysts.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Chunran Zhao,Chenrui Wang,Xujie Ren,Shude Yuan,Leihong Zhao,Lvchao Zhuang,Botao Teng,Ying Wu,Yiming He
Fabricating heterophase junctions proves to be an efficient strategy for achieving efficient charge separation and enhancing the catalytic activity of photocatalysts. Surprisingly, this approach is rarely utilized in the field of piezocatalysis. In this work, a novel ZnSnO 3 heterophase junction catalyst was fabricated by combining rhombohedral (R-ZnSnO 3 ) and orthorhombic (O-ZnSnO 3 ) phases for efficient piezo and piezo-photocatalytic RhB degradation and N 2 fixation. The piezocatalytic RhB degradation rates of ZnSnO 3 heterophase catalysts are 5.6 and 3.6 times higher than those of O-ZnSnO 3 and R-ZnSnO 3 , respectively, with similar enhancements observed in piezocatalytic N 2 fixation. The coupling of R-ZnSnO 3 and O-ZnSnO 3 does not increase the piezoelectric properties; however, an S-scheme structure formed at the interface. Under the combined effects of band bending, interface electric fields, and Coulomb attraction, electrons and holes migrate and achieve effective spatial separation. This result supports the energy band theory over the induction charge theory, contributing to the ongoing debate in piezocatalytic mechanisms. Electrochemical analyses and piezo-photocatalytic tests further indicate that ZnSnO 3 heterophase junctions exhibit a synergistic effect between piezocatalysis and photocatalysis. This synergy can be attributed to the complementary effects of photoinduced carrier generation and piezoelectric field-assisted carrier separation. Hydroxyl radicals, superoxide radicals, and holes serve as the primary active species responsible for piezocatalytic RhB degradation through a mechanism similar to photocatalysis. Theoretical calculations reveal that the Sn site on the surface of O-ZnSnO 3 acts as the active site within the ZnSnO 3 heterophase junction, providing valuable insights for future catalyst development. This work offers a deeper understanding of the synergistic mechanisms in piezo-photocatalysis, presenting a promising route for efficient environmental and energy applications.
研究领域:
材料科学
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环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Wanyue Qian,Yunzhe Wang,Liang Liu,Yihan Yang,Guoxiang Zhang,Shuquan Huang,Jianjian Yi
Phase engineering plays a critical role in enhancing photocatalytic performance of metal oxides. Herein, we demonstrate the phase-selective synthesis of MoO 3 (hexagonal h-MoO 3 , orthorhombic α-MoO 3 , and their junction h/α-MoO 3 ) through controlled phase transitions by adjusting annealing conditions. As evidenced with photocatalytic hydrogen evolution reaction, h/α-MoO 3 (14.20 μmol/h) phase junction shows superior performance to either h-MoO 3 (9.62 μmol/h) or α-MoO 3 (11.31 μmol/h), with a hydrogen yield of 47.6% and 25.6% greater than that of h-MoO 3 and α-MoO 3 (Pt as cocatalyst), respectively. A systematic study of the chemical structure characterizations, photochemical tests, band structure analysis, and photocatalytic activity evaluation reveal that, the enhancement is attributed to the strong built-in electric field in the h/α-MoO 3 phase junction, which effectively facilitates charge separation. Our findings introduce a novel strategy for improving photocatalytic performance using phase engineering.
研究领域:
材料科学
·
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）