JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
·
IF 6.361
Liwang Liu,Hong Li,Zirui Liu,Ya-Hong Xie
Colloidal quantum dots (QDs) have attracted a great amount of attention for their appealing optoelectronic properties. In this work, the CuInS 2 (CIS)/ZnS core/shell QDs based on 4.3 nm cores with various layers of ZnS shell (0 to 10) were synthesized. With the sequential growth of a ZnS shell over a CIS core, the band alignment of core/shell QDs converts from a type I to quasi-type II structure. This conversion prolongs the carrier lifetime and affects the electron transfer rate ( K et ) and electron transfer efficiency ( η ET ). A comparative study indicates that the photovoltaic performance of CIS based QDSCs can be markedly improved by optimizing the layers of ZnS shell. The highest photo conversion efficiency (PCE) of 2.07% is obtained at optimum ZnS thickness of about 1.55 nm. These results show tuning the thickness of shell to change the band alignment is an effective strategy to manipulate the carriers transportation behaviors and thus affect the PCE of CIS-based optoelectronic devices.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
·
2020
·
IF 9.567
Dong Li,Xiaoli Zhang,Muhammad Ramzan,Kai Gu,Yu Chen,Jiatao Zhang,Bingsuo Zou,Haizheng Zhong
Shell thickness control of core/shell quantum dots (QDs) plays an important role in determining their optical properties as well as the corresponding device performance. PbSe-based core/shell QDs are attractive near-infrared (NIR) light emitters for photonic and optoelectronic applications. We herein report the colloidal synthesis of giant shell PbSe-based core/shell QDs through controllable reactions between preformed PbSe QDs and Cd2+ ions in polar solvents. The preformed PbSe QDs experienced cation-exchange reaction in N,N-dimethylformamide (DMF), while they underwent epitaxial growth of CdS shell in dimethyl sulfoxide (DMSO). The cation exchange of preformed PbSe QDs in DMF result in PbSe/CdSe core/shell QDs with similar size (ca. 6.3 nm) but tunable shell thickness from 0.5 to 2.9 nm. In comparison, the epitaxial growth of preformed PbSe QDs in DMSO produce PbSe/CdS core/shell QDs in DMSO with average core size of ∼5.7 nm but tunable shell thickness from 0.5 to 3.1 nm. These resulting PbSe-based core/shell QDs show tunable photoluminescence emission of 1393–1744 nm for PbSe/CdSe core/shell QDs and 1566–1719 nm for PbSe/CdS core/shell QDs. The cation exchange and epitaxial growth reactions of preformed PbSe QDs were further investigated by comparing the interactions between solvents and cation ions through nuclear magnetic resonance (NMR) measurements. The interactions between Cd2+ and DMSO are stronger than that of DMF, while the interactions between Pb2+ and DMSO are weaker than that of DMF. The difference accounts for the reaction transition from cation exchange to epitaxial growth, providing alternative route for fabricating shell controllable PbSe-based core/shell QDs.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2024
·
IF 6.7
Shihong Lin,Bingyan Chen,Ying Xu,Zhiyu Li,Yuanrong Liao,Jun Wang,Peiyan Yu,Yang Zhang
Synergistic surface-enhanced Raman spectroscopy (SERS) substrates, leveraging the combined strengths of electromagnetic enhancement (EM) and chemical enhancement (CM), have been extensively explored in the literature. In this study, we introduce a distinctive approach to fabricating core@shell structures, specifically employing silver nanowire @ zeolite imidazole framework-8 (AgNW@ZIF-8) as synergistic SERS substrates. Notably, these substrates offer meticulous control over shell thickness through a straightforward post-synthesis procedure. Utilizing Ag nanowires as the plasmonic core, selected for their broader localized surface plasmon resonance (LSPR) absorption range compared to nanoparticles , we encapsulate them within ZIF-8, a metal-organic framework (MOF) recognized for its proficient charge transfer (CT) properties. Our investigation encompasses the SERS performance across various Raman-active molecules, considering their diverse sizes and distinct frontier molecular orbitals (FMO) energy levels. Additionally, we systematically explore the influence of alterations in shell thickness on SERS outcomes and scrutinize the impact of probe orientation. This comprehensive study not only advances the understanding of synergistic effects intrinsic to MOFs-metal SERS substrates but also provides valuable insights for the rational design of highly sensitive substrates tailored for practical applications.
研究领域:
材料科学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2025
·
IF 9.8
Yahui Xu,Hanbo Wang,Zikai Wang,Yan Wang,Dongyu Zhu,Ziming Wang,Kechang Li,Yumei Tian,Haiyan Lu
Hollow carbon spheres (HCSs) attracted increasing attention in the field of supercapacitor materials owing to their unique hollow structure. However, their hollow shells exhibited weak mechanical strength and tended to collapse under high-rate cycling. In this study, a nitrogen/sulfur co-doped hollow carbon sphere (NS-HCS) with tunable shell thickness was synthesized by adjusting the shell thickness and dopant loading. The optimized NS-HCS-1 integrated double-layer and pseudocapacitive storage while retaining the intrinsic high-power characteristics of carbon materials. The appropriate shell thickness enhanced structural durability, whereas N and S doping enriched the pore structure, accelerated ion transport, and provided additional pseudocapacitance, thereby improving electrochemical performance. In a three-electrode system, the material delivered a specific capacitance of 366 F g −1 at 1 A g −1 and retained 98.42 % of its initial capacitance after 20,000 cycles at 15 A g −1 . The assembled symmetric cell achieved a maximum energy density of 34.08 Wh kg −1 and a power density of 570 W kg −1 . This synergistic engineering of shell thickness and heteroatom doping afforded outstanding electrochemical performance, rendering NS-HCS-1 a promising electrode candidate for next-generation supercapacitors.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
功能材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Ali Shmshad,Jialun Tang,Imran Muhammad,Dengbao Han,Xin Zhang,Shuai Chang,Qingfan Shi,Haizheng Zhong
Colloidal quantum dots (QDs) are talented materials and have been extensively investigated in the field of photonics and optoelectronics due to their size-dependent optical properties. The core/shell structure of QDs with a wide band gap shell has been adopted for obtaining stable emission and high photoluminescent (PL) quantum efficiency. However, when employed in active devices such as light-emitting diodes (LEDs), the thick-shell structure of QDs may impede the transportation of carriers, thus deteriorating the device performance. In this work, the effect of the shell thickness of CdSe/ZnS QDs on the device performance is systematically studied through impedance spectroscopy, by constructing the electron-only symmetric device architecture. It is found that the evolution of capacitance in the symmetric device under applied voltage reflects the charge accumulation within the device and predicts the LED performance. The lowest capacitance is evaluated in the symmetric device containing QDs with a medium shell size of 2.1 nm, showing improved performance in the LED with the highest luminance and current efficiency of 26 370 cd/m2 and 8.3 cd/A, respectively.
研究领域:
光子学
·
光电学
·
材料科学
✓ 已验证
DOI
高影响因子
FERROELECTRICS
·
2018
·
IF 0.728
Hui Zhang,Qi Tang,Lilong Gao,Hua Yuan,Hai-Lin Cong,Bing Yu
ABSTRCTCore-shell structure particles are attracting considerable attention because of their applications in drug delivery and catalysis carrier. In this study, SiO2@SiO2 core-shell structure with tunable shell thickness was successfully prepared by using tetraethoxysilane (TEOS) as the silica source. Monodisperse nonporous silica spheres with a diameter of 1.7 μm were synthesized by a modified Stöber method. An template CTAB was first grafted onto the SiO2 microsphere surface. Then TEOS was hydrolyzed with the addition of ammonia. Finally, superficially porous core-shell SiO2@SiO2 microspheres were obtained through calcination to remove the template.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Jiao Li,Pinggui Tang,Jiajun Zhang,Yongjun Feng,Ruixian Luo,Aifan Chen,Dianqing Li
A facile method to prepare SnO2 hollow microspheres has been developed by using SiO2 microspheres as template and Na2SnO3 as tin resource. The obtained SnO2 hollow microspheres were characterized by X-ray diffraction, scanning electron microscopy, high resolution and transmission electron microscopy, and Brunauer–Emmett–Teller analysis, and their sensing performance was also investigated. It was found that the diameter of SnO2 hollow microspheres can be easily controlled in the range of 200–700 nm, and the shell thickness can be tuned from 7.65 to 30.33 nm. The sensing tests showed that SnO2 hollow microspheres not only have high sensing response and excellent selectivity to acetone, but also exhibit low operating temperature and rapid response and recovery due to the small crystal size and thin shell structure of the hollow microspheres, which facilitate the adsorption, diffusion, and reaction of gases on the surface of SnO2 nanoparticles. Therefore, the SnO2 hollow microsphere is a promising material for the preparation of high-performance gas sensors.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2013
·
IF 2.112
Lei Wang,Lixin Cao,Ge Su,Wei Liu,Chenghui Xia,Huajian Zhou
The synthesis and luminescent properties of water-soluble ZnSe:Cu/ZnS core/shell quantum dots (QDs) with different shell thickness are reported in this paper. X-ray powder diffraction (XRD) studies present that the ZnSe:Cu/ZnS core/shell QDs with different shell thickness have a cubic zinc-blende structure. The tests of transmission electron microscope (TEM) pictures exhibit that the QDs obtained are spherical-shaped particles and the average grain size increased from 2.7 to 3.8 nm with the growth of ZnS shell. The emission peak position of QDs has a small redshift from 461 to 475 nm with the growth of ZnS shell within the blue spectral window. The photoluminescence (PL) emission intensity and stability of the ZnSe:Cu core d-dots are both enhanced by coating ZnS shell on the surface of core d-dots. The largest PL intensity of the core/shell QDs is almost 3 times larger than that of Cu doped ZnSe quantum dots (ZnSe:Cu d-dots). The redshift of core/shell QDs compared with the core QDs are observed in both the absorption and the photoluminescence excitation spectra.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2020
·Vol. 10
·期 4
·325
·
IF 2.404
Liqing Liu,Hui Wang,Dehao Wang,Yongtao Li,Xuemin He,Hongguang Zhang,Jianping Shen
The ZnO@TiO2core/shell nanowire arrays with different thicknesses of the TiO2shell were synthesized, through depositing TiO2on the ZnO nanowire arrays using the pulsed laser deposition process. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images show that these core/shell nanowires were homogeneously coated with TiO2nanoparticles with high crystallinity, appearing to be a rather rough surface compared to pure ZnO nanowires. The efficiency of ZnO@TiO2core/shell structure-based dye-sensitized solar cells (DSSCs) was improved compared with pure ZnO nanowires. This is mainly attributed to the enlarged internal surface area of the core/shell structures, which increases dye adsorption on the anode to improve the light harvest. In addition, the energy barrier which formed at the interface between ZnO and TiO2promoted the charge separation and suppressed the carrier recombination. Furthermore, the efficiency of DSSCs was further improved by increasing the thickness of the TiO2shell. This work shows an efficient method to achieve high power conversion efficiency in core/shell nanowire-based DSSCs.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 84
·53104-53110
·
IF 3.108
Jian Liu,Zhongzhu Wang,Sajid ur Rehman,Hong Bi
Highly uniform core–shell polypyrrole@carbon microspheres (PPy@CM) have been successfully constructed by oxidation polymerization of pyrrole as the shell on the core of carbon microspheres. The thickness of the PPy shell can be easily controlled by modulating the weight ratio of pyrrole monomer and carbon microspheres. Hydrophilic carbon microspheres with abundant hydroxyl groups have a very strong affinity to the conjugated chains of PPy, which is responsible for the spontaneous formation of the uniform core–shell structure. Coating the PPy shell on the carbon core could increase the complex permittivity and dielectric loss due to an additional interfacial polarization. With a proper thickness of the PPy shells, the improved dielectric loss would be induced. The microwave absorbing properties of the PPy@CM powders were investigated by dispersing them in paraffin wax with 40 wt% powders in the frequency range of 2–18 GHz. The PPy@CM-0.6 (0.6 g CM) sample exhibits the maximum reflection loss of −38.1 dB at 11.6 GHz and a bandwidth of less than −10 dB covering 11.17 to 12.26 GHz with the thickness of 3 mm. In addition, the absorption peak sites and bandwidth of the PPy@CM composites can be easily modulated not only by the thickness of the absorbers but also of the PPy shell of the PPy@CM composite. Thus, the PPy@CM composites can be considered as a new type of promising lightweight microwave absorbers to satisfy the applications of microwave absorption in the 8–18 GHz range.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2015
·
IF 2.489
Haibo Duan,Jingjing Diao,Naru Zhao,Yijuan Ma
Hollow mesoporous bioactive glass microspheres (HMBGMs) were fabricated via a hydrothermal-assisted self-transformation method employing cetyltrimethyl ammonium bromide (CTAB) as a mesoporous template. The morphology, structure, particle size and specific surface area of HMBGMs were characterized by various methods. The results demonstrated that the solid BG spheres prepared in a Sto¨ber solution could spontaneously transform to hollow structure by incubating in hydrothermal condition. Meanwhile, the shell thickness of HMBGMs could be controlled by the hydrothermal time. In vitro drug release studies demonstrated that the HMBGMs exhibited a sustained release property. The obtained HMBGMs may have potential applications in drug delivery and bone tissue regeneration.
研究领域:
材料科学
·
生物医学工程
·
药物递送系统
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2025
·
IF 5.6
Zhu Dongyu,Wang Yan,Yang Xingchen,Wang Hanbo,Xu Yahui,Wang Ziming,Tian Yumei,Lu Haiyan
Electrochemical supercapacitors must simultaneously deliver high power density, long life, and rising volumetric energy, yet converting surface area rich carbons into compact, fast, and durable electrodes remains nontrivial. Hollow spherical structures have been extensively studied for their application as supercapacitor electrode materials due to their large specific surface area, regular morphology, and numerous modification sites. This work focuses on the precise control of the shell layer thickness of hollow carbon spheres (HCS) while introducing nitrogen atoms via a one-step method to further enhance the material’s volumetric active material density. The resulting HCS-N-1 exhibits an excellent specific capacitance of 381 F g -1 at 1 A g -1 in a three-electrode system, and maintains an astonishing capacitance retention rate of 97.45% after 20,000 cycles at 10 A g -1 . The assembled symmetric supercapacitor (SSC) exhibits an preeminent energy density of 32.5 Wh kg -1 at a particularly excellent power density of 2463 W kg -1 , with only an 8.41% energy decay after 20,000 charge-discharge cycles. These impressive electrochemical properties highlight the strategic insights provided by this work for the structural design of high-performance hollow spherical carbon materials.
研究领域:
材料科学
·
电化学
·
纳米能源
·
储能材料
·
碳材料化学
✓ 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）