Nanomaterials
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2023
·Vol. 13
·期 3
·406
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IF 5.3
Beibei Jia,Jun Zhou,Jiaxin Chen,Zixuan Zhang,Yang Wang,Zepeng Lv,Kai Wu
Space charge accumulation greatly influences the dielectric performance of epoxy composites under high voltage. It has been reported that nano-fillers can suppress the charge accumulation in the bulk of insulation materials. However, it is still unclear how the nano-fillers influence the charge distribution at the interface between the filler and polymeric matrix. In this work, the dielectric properties and the local dynamic charge mobility behavior at the interface of barium titanate/epoxy resin (BTO/EP) composites were investigated from both bulk and local perspectives based on the macroscopic test techniques and in-situ Kelvin probe force microscopy (KPFM) methods. Charge injection and dissipation behavior exhibited significant discrepancies at different interfaces. The interface between BTO and epoxy is easy to accumulates a negative charge, and nanoscale BTO (n-BTO) particles introduces deeper traps than microscale BTO (m-BTO) to inhibit charge migration. Under the same bias condition, the carriers are more likely to accumulate near the n-BTO than the m-BTO particles. The charge dissipation rate at the interface region in m-BTO/EP is about one order of magnitude higher than that of n-BTO/EP. This work offers experimental support for understanding the mechanism of charge transport in dielectric composites.Keywords:interface;epoxy resin;charge transport;trap
研究领域:
材料科学
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电气工程
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产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2024
·
IF 3.3
Yu Xia,Guofang Huang,Yan Fan,Xiaolong Zhao,Lei Wang,Jingwei Huang,Houde She,Qizhao Wang
Semiconductor heterojunctions could accelerate carrier separation and transfer for improving light-to-hydrogen (LTH) conversion efficiency. However, the lack of tight and efficient interfacial charge cross in three-dimensional semiconductor-based heterojunctions limits their practical application and the relevant profound understanding of the interfacial charge delivery. In this work, porphyrin (Cu)-based COF with a highly conjugated structure was deposited onto three-dimensional (3D) ZnIn2S4 by a facile solvothermal method to prepare a 3D/2D ZnIn2S4@CuP–Ph COF heterojunction. The content-optimized ZnIn2S4@CuP–Ph COF composite showed an excellent LTH conversion rate of up to 2667.94 μmol g–1 h–1, about 13.5 times higher than that of pristine ZnIn2S4. The significantly meliorated photocatalytic performance is attributed to the synergistically functioning contributors, that is, the fast interfacial charge transfer and the augmented light capturing capability after integration. Also, the work function results by DFT calculation reveals that the electrons of CuP–Ph COF (Φ = 4.41 eV) transfer from the interface electron delivery channels of the two components to ZIS (Φ = 7.03 eV) until the Fermi level of the two components reaches equilibrium. This moment, the work function of ZnIn2S4@CuP–Ph COF (Φ = 6.50 eV) lies between the two components, and an electron accumulation region is formed on the side of ZIS. Additionally, the free-energy barriers of hydrogen evolution dominated by ZnIn2S4@CuP–Ph COF (0.0955 eV) is much lower than that of ZnIn2S4 (0.1256 eV). This study possesses certain guiding significance for the design of organic–inorganic heterojunction photocatalysts for efficient LTH conversion.
研究领域:
材料科学
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能源科学
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化学工程
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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
Sicheng Zhang,Tengfei Duan,Dejian Yan,Hongyun Yang,Lingling Cheng,Yong Pei,Kuiyi You,He'an Luo
Charge recombination at the interface of oxygen evolution catalyst (OEC) and BiVO 4 -based photoanode is one of the great challenges to achieve efficient photoelectrochemical (PEC) water splitting due to the poor charge transfer and separation efficiency of BiVO 4 . Herein, a composite photoanode (NiFe/C-Mo:BiVO 4 ) consisting of a molybdenum doped BiVO 4 photoanode, an OEC interfacial layer of NiFeOOH and a tailorable hole transfer layer (HTL) made of glucose-derived carbon in between, was designed and fabricated for highly efficient PEC water splitting. The composite NiFe/C-Mo:BiVO 4 photoanode exhibited the photocurrent density of 5.62 mA cm −2 at 1.23 V RHE and an outstanding photo-stability. Characterization and photoelectrochemical analyses revealed that the inserted carbon HTL, though not active for surface water oxidation kinetics, greatly suppressed the unwanted recombination of electron-hole pairs and drastically improved the transfer and storage of charge carriers at the OEC/BiVO 4 interface. A surface charge separation efficiency of 89 % at 1.23 V RHE and remarkable hole storage properties were obtained. This work afforded a novel approach to the design of low-cost and sustainable HTL integrated photoanodes for efficient PEC water oxidation.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
Carbon Letters
·
2023
·Vol. 33
·期 5
·1395-1406
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IF 4.5
Chen Zhangjing,Li Liangliang,Cheng Gang
Photocatalytic CO 2 reduction is a promising approach for reducing CO 2 emissions and achieving the goal of carbon neutrality. In this work, selectively coupling Cu(OH) 2 and CuO with amine-modified brookite TiO 2 (NH 2 –B–TiO 2 ) has been achieved by a simple precipitation method. The results show that CuO is better than Cu(OH) 2 as a co-catalyst to enhance the CO 2 photoreduction capability of NH 2 –B–TiO 2 . The highest rates of CO 2 conversion to CH 4 and CO of NH 2 –B–TiO 2 –CuO composite reach 6.05 and 3.25 μmol h −1 g −1 , respectively, which is higher than 8 times the yield of CH 4 of NH 2 –B–TiO 2 . It is proposed that the NH 2 –B–TiO 2 –CuO composite offers an effective charge transfer through the formation of a p–n junction between NH 2 –B–TiO 2 and CuO interfaces, while in the NH 2 –B–TiO 2 –Cu(OH) 2 composite, the Cu(OH) 2 dominantly serves as an electron sink to capture photo-induced electrons, promoting photo-induced carrier separation. This work provides an ingenious synthetic method for selectively anchoring Cu(OH) 2 and CuO on semiconductors with different charge transfer routes for an efficient CO 2 photoreduction. Graphical abstract
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
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
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2021
·Vol. 168
·期 11
·116513
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IF 4.316
Yuanyuan Jiang,Rajesh Pathak,Tiansheng Zhang,Haibin Xu,Xiaoyi Li,Ronghua Jian,Fan Wu
The solution-processed TiO2/BiFeO3/BiOI ternary heterojunction with cascade energy level alignments was developed for photoelectrochemical conversion, in which, BiOI was deposited on BiFeO3 sensitized TiO2 mesoporous film by spin-coating method. BiFeO3 as ferroelectric material was served here as a mediator for improvement of charge separation and transfer. The photocurrent generation in TiO2/BiFeO3/BiOI sample are very stable, even measured after 50 light on/off cycles with 2000 s. Moreover, compared with the TiO2/BiOI film, TiO2/BiFeO3/BiOI film showed about twice as high photocurrent density and photocatalytic activity. Kelvin probe force microscope showed that the surface potential of TiO2/BiFeO3/BiOI film was 0.456 V, which was obviously larger than 0.226 V in TiO2/BiOI sample. The increased surface potential should originate from the polarization electric-field Eself by BiFeO3 interlayer, in which the direction of electric-field was directed toward the BiOI. The presence of Eself consequently resulted in the better dissociation of photo-generated electrons and holes. Charge transport dynamics suggested that charge transfer rate increased from 6.813 s−1 of TiO2/BiOI heterojunction to 22.280 s−1 of TiO2/BiFeO3/BiOI heterojunction, and surface charge recombination rate reduced from 10.305 s−1 of the TiO2/BiOI to 7.707 s−1 of TiO2/BiFeO3/BiOI heterojunction, which results in the enhanced photoelectrochemical conversion in TiO2/BiFeO3/BiOI heterojunction.
研究领域:
材料科学
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光电化学
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纳米技术
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能源材料
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Nuo Zhang,Bingzhu Wang,Pengcheng Hu,Zhenxing Gao,Haiwang Wang
MCNTs-CdS has been identified as a promising material for photocatalytic hydrogen production due to its strong visible-light responsiveness and suitable energy band structure. However, the rapid complexation of its photogenerated electrons and holes makes its photocatalytic hydrogen production unsatisfactory. To address the above problem, MCNTs-CdS/Pt/ZnFe 2 O 4 composites were designed in this paper, and Pt was used as an electronic bridge to realize the fast transfer of electrons between the two semiconductors. The results show that the carrier transport resistance of MCNTs-CdS/Pt/ZnFe 2 O 4 system is greatly reduced, and the electron-hole separation rate is significantly better than that of MCNTs-CdS. In addition, the results of the photolysis of water hydrogen production demonstrated that when the deposition amount of Pt was 8 % and the mass ratio of MCNTs-CdS to ZnFe 2 O 4 was 1:0.1, the hydrogen production rate reached its maximum (1100.82 μmol/g/h), which was 35.51 times higher than that of MCNTs-CdS. The metal Pt functions as an electronic bridge to realize rapid electron transfer and MCNTs-CdS/Pt/ZnFe 2 O 4 form a Z-scheme carrier transport mechanism.
研究领域:
材料科学
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能源科学
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纳米技术
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产品关联
DOI
高影响因子
Frontiers of Optoelectronics
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2022
·Vol. 15
·期 1
·1-10
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IF 0
Jiang Mengjia,Li Shuyu,Zhen Chun,Wang Lingsong,Li Fei,Zhang Yihan,Dong Weibing,Zhang Xiaotao,Hu Wenping
Simultaneously realizing the optical and electrical properties of organic materials is always challenging. Herein, a convenient and promising strategy for designing organic materials with integrated optoelectronic properties based on cocrystal engineering has been put forward. By selecting the fluorene (Flu) and the 7,7′,8,8′-tetracyanoquinodimethane (TCNQ) as functional constituents, the Flu-TCNQ cocrystal prepared shows deep red emission at 702 nm, which is comparable to the commercialized red quantum dot. The highest electron mobility of organic field-effect transistor (OFET) based on Flu-TCNQ is 0.32 cm 2 V −1 s −1 . Spectroscopic analysis indicates that the intermolecular driving force contributing to the co-assembly of Flu-TCNQ is mainly charge transfer (CT) interaction, which leads to its different optoelectronic properties from constituents. Graphical Abstract
研究领域:
材料科学
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光学
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电子工程
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产品关联
DOI
PubMed
JOURNAL OF POWER SOURCES
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2022
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IF 9.794
Yan Lei,Ruijuan Qi,Jinpeng Wu,Haodan Guo,Xiangrong Li,Yanyan Fang,Dongmei Xie,Yuan Lin
The III-V group colloidal quantum dots (CQDs) have been successfully synthesized with stable and low-cost chemical reagents recently, but they are rarely used for solid state solar cells due to the poor charge carrier transfer in solid films. In this work, the surface of InZnP (Zn doped InP) CQDs has been reconstructed with PbS via a chemical engineering strategy. Comparing with InZnP CQDs, the long carbon chain ligands capped on the InZnP@PbS CQDs surface can be easily exchanged with small molecules. By capping the mercaptopropionic acid (MPA) onto the InZnP@PbS CQDs surface, the electrical coupling between the InZnP@PbS CQDs has been established, and the photoinduced charge carrier transfer has been significantly enhanced. Based on the above CQDs, solid state solar cell devices are assembled, achieving about 1.5% of power conversion efficiency (PCE). The photoelectric performances of the fabricated solar cells almost do not decay after 150 days storage. Current work may provide a new way for III-V group CQDs application in solution-processed optoelectronics .
研究领域:
材料科学
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光电子学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2018
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IF 11.698
Hongwen Zhang,Lei Ma,Jintao Ming,Bingqian Liu,Yibo Zhao,Yidong Hou,Zhengxin Ding,Chao Xu,Zizhong Zhang,Jinlin Long
This work demonstrated the 12 fold-enhanced solar water splitting over the type-II core-shell nanostructured TiO 2 rutile photoanodes by orienting the charge flow and accelerating the hole transport to water-oxidation sites. Such nanoheterostructured photoanodes were designed rationally and prepared by a facile strategy to enwrapping an amorphous Ta 2 O x N y layer on surface of TiO 2 nanorods grown on the FTO glass substrates, consequently the incident photon-to-current conversion efficiency was increased from 2.2% to 22.6% in a two-electrode system under 390 nm light irradiation. The activity results showed that under AM 1.5 G illumination, the photocurrent output of TiO 2 @Ta 2 O x N y photoanodes reached a stable density of 1.32 mA cm −2 at 1.23 V vs RHE, and which is 12 times and ca. 4.3 times than that of the pristine TiO 2 and TiO 2 @Ta 2 O 5 counterparts, respectively. Correspondingly, the oxygen evolution rate was improved from 20.3 to 112.7 mmol m −2 h −1 . A solar-to-chemical energy conversion efficiency of ca. 1.49% was achieved at 1.23 V vs RHE.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
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IF 24.319
Yizhou Wu,Yu Chen,Donglin Li,Dania Sajjad,Yixuan Chen,Yiying Sun,Shusong Liu,Jiafu Shi,Zhongyi Jiang
Heterostructure materials are increasingly utilized in solar energy conversion to pursue high efficiency and long-term stability. The charge transfer across interfaces gives rise to major energy loss arising from non-ideal interfacial effects, i.e., high interfacial energy barrier and low interfacial contacting area. Herein, we demonstrate a facile interface engineering strategy to eliminate non-ideal interfacial effects. A heterojunction of CN@C-P25 is constructed via polyphenol-assisted assembly of titania (P25) and carbon nitride (CN). The uniform dispersion of P25 on CN enlarges the interfacial contacting area of 3.2-fold compared with random dispersion, while the transformation of polyphenols into conjugated carbon facilitates the interfacial charge transfer by switching a 0.4 eV Schottky contact to a 0.1 eV Ohmic contact between CN and P25. A 2.5-fold enhancement of charge transfer flux is obtained with an initial reaction rate of 5185 μmol h −1 g −1 for photocatalytic nicotinamide regeneration.
研究领域:
材料科学
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能源转换
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界面化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
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IF 9.965
Tong Wang,Lili Gao,Peng Wang,Xuefeng Long,Huan Chai,Feng Li,Jun Jin
Aiming at the drawbacks of hematite like poor conductivity and tardy oxidation kinetics, herein, we utilized dual dopants in the bulk and surface to ameliorate the situation. Specifically, doping optimal amount of Zr 4+ in the hematite (Zr:Fe 2 O 3 ) enhances the conductivity of hematite due to the higher charge carrier density. Further, F:FeOOH could form p-n heterojunction in bulk where a potential barrier is built up that repels electrons but prompts holes transferring to F:FeOOH for water oxidation. What’s more, the high electronegative of F - would withdraw electron from the Fe site in FeOOH, and the enhanced positive electricity of Fe 3+ is beneficial for adsorption of OH – as well as enhance the conductivity of FeOOH to expedite holes transfer. As a result, the composite photoanode (F:FeOOH/Zr:Fe 2 O 3 ) shows a 3.25-times enhanced photocurrent density comparing with α-Fe 2 O 3 . The special designation employs ultrathin F:FeOOH to act as both p-type semiconductor and efficient co-catalyst, avoiding redundant layer that would extend the migration distance of holes. On the top of that, the dual modification approach provides an extensive prospect for the further application of hematite.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Fangxia Xie,Qing Xi,Mei Zhang,Rui Li,Xiaoming Gao,Houfen Li,Xiaochao Zhang,Yawen Wang,Yunfang Wang,Xiuping Yue,Jianxin Liu,Caimei Fan
Directing the transfer of photoinduced charges to various reaction sites through catalyst design plays crucial roles in enhancing photocatalytic oxygen evolution. Herein, we used a facile alcoholysis method to synthesize amorphous FeOOH modified light-switchable oxygen vacancies BiOBr, which exhibited outstanding photocatalytic oxygen evolution activity. Density functional theory calculations, photoelectronchemical tests and kelvin probe force microscopy revealed that FeOOH overlayer acts as the hole storage layer, while oxygen vacancies (OVs) provided a number of electron trap centers. Benefiting from this synergistic effect, the photogenerated charges showed an outstanding directional transfer performance, which greatly prolong the lifetime of the photo-induced charge carriers. Moreover, as a cocatalyst for water oxidation, FeOOH can effectively lower the kinetics barriers and provide more active sites for oxygen evolution reaction. Therefore, under simulated sunlight irradiation, the 2%FeOOH/BiOBr photocatalyst demonstrated remarkable photocatalytic activity towards oxygen evolution, achieving a rate of 284.34 μmol·g −1 ·h −1 , which is around 1.71 folds than pure BiOBr. Finally, the possible reaction mechanism has also been discussed. This work has provided valuable insights and inspiration for the effective design and optimization of BiOBr-based catalysts, which play a critical role in facilitating efficient directional transfer of photogenerated charges.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）