Catalysis Science & Technology
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2020
·Vol. 10
·期 11
·3709-3719
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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
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光催化
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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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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
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DOI
PubMed
高影响因子
ACS Applied Energy Materials
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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
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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
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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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
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催化化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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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
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化学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
·
IF 4.65
Yingnan Zhao,Xinyu Zhao,Zhongling Lang,Huiying Sun,Zhilu Du,Huaqiao Tan,Tianyu Qiu,Wingkei Ho,Zhao Zhao,Yonghui Wang
Phase junction can effectively improve spatial charge separation due to its good lattice matching at the interface. Developing phase junction materials with good visible light absorption and suitable electronic band structure is greatly important for photocatalytic environmental purification. In this work, we combined the P and I phases of Cu 2 MoS 4 (CMS) by one-step solvothermal in situ phase transition route. The as-prepared samples are labeled as CMS-X, where X represents the reaction time (X = 2, 4, 6, 8, 10, 12, 24 h). XRD , SEM, HRTEM , and XPS confirmed the existence of the phase junction structure. Photocatalytic experiments revealed that the phase junction samples exhibit excellent photocatalytic performance and durability for methyl orange (MO) and tetracycline (TC) degradation. Among the samples, CMS-8h showed optimal phase composition and the best photocatalytic degradation performance. Approximately 50 ml of 20 ppm MO can be completely degraded within 8 min under visible light irradiation, which is approximately 12.5 and 10 times faster than that of pure phase P-CMS and I-CMS respectively, presenting the best photocatalytic efficiency of CMS. Photocatalytic mechanism studies combined with theoretical calculations demonstrated that CMS-8h (PI-CMS) possesses a typical type-II heterojunction structure, which significantly accelerates the separation of photogenerated carriers and reduces their radiation recombination. The synergistic effect of the advantages of each phase and optimized interfacial band alignment endow PI-CMS with highly efficient and long-lasting photocatalytic activity for organic pollutant degradation.
研究领域:
材料科学
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环境科学
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化学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Jianan Dai,Chao Wu,Jing Ma,Shu-Hao Chang,Weiwei Liu
The conventional heterojunction formed by combining two different semiconductors is associated with issues of low compatibility, restricted intimate contact, and limited charge anti-recombination process. To address these issues, a simple strategy was adopted to fabricate a hetero-phase junction flanked with two dissimilar crystal phases of a single semiconducting material . This study employed TiB 2 as the initial material to fabricate an anatase/rutile TiO 2 hetero-phase junction material (AR-TiO 2 ), followed by its combination with highly conductive monolayer Ti 3 C 2 nanosheets to develop an AR-TiO 2 /Ti 3 C 2 composite photocatalyst . The photocatalyst displayed a wide range of light absorption and a remarkable capability for separating photogenerated carriers. The closely interconnected hetero-phase junction surface, formed by the rutile and anatase phases of AR-TiO 2 , combined with the incorporation of highly conductive Ti 3 C 2 nanosheets , synergistically increased the availability of multi-dimensional active sites and increased the efficacy of separating photogenerated electron pairs. The optimized AR-TiO 2 /Ti 3 C 2 achieved a degradation efficiency of 91.49 % for tetracycline hydrochloride (TCH) within 2 h and produced 1005.81 μmol of hydrogen in 6 h. The impacts of initial pH, co-existing anions, initial TCH concentration, initial temperature, and various pollutant species on the catalytic efficiency were also investigated. pH was shown to have the greatest impact on the photocatalytic performance of AR-TiO 2 /Ti 3 C 2 for TCH degradation. •O 2 − , and h + were identified as the primary reactive species that enabled the photocatalytic performance of AR-TiO 2 /Ti 3 C 2 through trapping experiments. This study presents a novel method to synthesize hetero-phase junction photocatalysts and suggests that Ti 3 C 2 has potential prospects for use in photocatalysis .
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF CHEMICAL PHYSICS
·
2020
·Vol. 152
·期 24
·
IF 2.991
Zhu Jingxian,Jiang Wenshuai,Wang Bin,Niu Lijuan,Dong Chenxi,Qu Dan,An Li,Wang Xiayan,Sun Zaicheng
Mixed phase TiO 2 (Degussa P25) exhibits superior photocatalytic performance and stability due to the formation of the hetero-phase junction between anatase and rutile. However, the large bandgap limits its visible light activity. CdS is a photocatalyst with a broad light absorption band up to 550 nm. Constructing a hetero-phase junction will greatly promote the photocatalytic activity of CdS. In this work, the one-step solvothermal method was used to synthesize CdS hetero-phase junction with both hexagonal wurtzite (WZ) and cubic zinc blende (ZB) phases. The ratio of WZ and ZB phases can be tuned by adjusting the solvent ratio and reaction time to construct type I junction and effectively separate the photogenerated electron–hole pair. Under visible-light illumination, the optimal photocatalytic activity of the prepared material reaches 7.96 mmol h −1 g −1 , and the quantum efficiency is 36.7% at 420 nm, which is three times higher than that of any single-phase sample (cubic or hexagonal phase) and maintains high photocatalytic stability as well. It is expected that this work will provide a feasible prospect for the practical application of high-efficiency homogeneous junction photocatalysts.
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
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Changchao Jia,Tao Dong,Meng Li,Peng Wang,Ping Yang
TiO 2 hollow hierarchical architectures with anatase and rutile phases are fabricated. The hierarchical structure uniformly decorated with SnO 2 nanoparticles endows a fascinating sensing performance for detecting triethylamine (TEA). Hierarchical structure provides a close connection between anatase/rutile TiO 2 and SnO 2 , which is in favor of efficient electrons transfer . It is found that TiO 2 @SnO 2 as a novel sensing material has high response at low level of TEA and rapid responding speed in comparison with individual TiO 2 components. In the case of 5 ppm TEA gas under the operation temperature of 240 °C, the response value of TiO 2 @SnO 2 sample is up to 21.6, which is three times higher than that of TiO 2 sample. The responding speed of TiO 2 @SnO 2 sensors elevates 28% in comparison with TiO 2 . This result is utilizable for developing the high efficiency gas sensors using hollow hierarchical architecture.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 24
·14613-14619
·
IF 10.733
Qian Wang,Huaiyan Ren,Yingqiang Zhao,Xinyuan Xia,Fang Huang,Guanwei Cui,Bohui Dong,Bo Tang
The phase junction of nano-TiO2 plays an important role in enhancing its photocatalytic activity. However, the achievement of the green, mild and controllable synthesis of phase-junction nano-TiO2 still remains a big challenge for the large-scale preparation and application. Deep eutectic solvents (DESs) show many advantages in the green and mild preparation of highly active nanomaterials due to their low cost, high environmental friendliness, easy large-scale preparation, tailored structures and tunable properties. In this study, by sharing two H-bond acceptors with one H-bond donor, we successfully used DES as a solvent, template, inhibitor and crystalline phase control agent simultaneously to controllably synthesize heterophase-junction nano-TiO2 with different phase ratios under green and mild reaction conditions (at 180 °C for 18 h). The H2 production rate of photocatalytic water splitting with this catalyst reached up to 14.51 mmol h−1 g−1, which was 20-fold greater than that of commercial P25 TiO2 and also much higher than those of other TiO2 nanostructures. To the best of our knowledge, this rate is the highest value reported so far for photocatalytic H2 production catalyzed by sole TiO2. This higher activity was mainly attributed to the phase junctions and defects. This study will provide a new way for the green, mild, easily controllable and versatile preparation of phase-junction photocatalysts with high efficiency.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）