Advanced Optical Materials
·
2024
·
IF 8
Yixuan Xu,Zihan Cheng,Henggang Wang,Jun Jiang,Zuxu Zhou,Linger Feng,Xiaomeng Wang,Hengwei Lin,Kai Jiang
Luminescent materials with time-resolved dynamic discoloring afterglow (TDDA) hold significant potential for applications in anti-counterfeiting and data encryption. However, the afterglows coming from organic systems are usually unidentifiable due to their shorter durations (less than 10 s). Achievement of long-lasting and visually discernible TDDA remains highly desirable but challenging. In this work, the TDDA duration is successfully extended from less than 10 s to minutes by engineering the luminescent centers of carbon dots (CDs) and introducing deep trap-states in a composite of CDs and carbon nitrides (CNs) (named Y-CDs@CN). It is confirmed that the regulation of luminescent centers in CDs containing both C═N and C═O bonds is responsible for the color changes during TDDA from yellow to green. Moreover, the generation of deep trap states is found to be significant for prolonging the afterglow duration to minutes level through converting room temperature phosphorescence into long persistent luminescence, thus making the entire dynamic discoloring process being easily recognized to naked eyes. Furthermore, the afterglow of Y-CDs@CN can also be excited by blue light and even using white light of a cell phone. To harness these characteristics, potential applications of Y-CDs@CN for portable anti-counterfeiting and multidimensional information encryption are primarily investigated.
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 Physical Chemistry C
·
2021
·
IF 4.126
Mengling Liao,Beibei Shan,Ming Li
All-inorganic CsPbBr3 perovskites have emerged as promising luminescent materials for light-emitting devices owing to their unprecedented photoluminescence (PL) properties. The fundamental understanding of their photophysical properties offers new opportunities to develop high-performance devices. However, the investigation of optical properties of strongly quantum-confined CsPbBr3 perovskites of different morphologies is lacking. Herein, we report the PL properties of strongly quantum-confined CsPbBr3 perovskites with varying dimensionalities, specifically zero-dimensional quantum dots (0D-QDs), one-dimensional quantum wires (1D-QWs), and two-dimensional quantum platelets (2D-QPLs). Results reveal that the PL efficiency displays an overall increase for 0D-QDs and 1D-QWs but a negligible change for 2D-QPLs against the excitation wavelength, all with the observation of multiple local minima. A combined analysis of the excitation wavelength dependence of the PL efficiency, dimensionality dependence of excitonic transition, and time-resolved PL decays implies the presence of two different types of trap states—a continuum of electron trap states and discrete localized trap states. We conclude that both trap states are equally important in both 0D-QDs and 1D-QWs, while discrete localized trap states are dominant in 2D-QPLs. In all these quantum structures, the two trap states do not affect the intrinsic exciton relaxation but could interact with energetically excited electrons beyond the conduction band minimum, thereby decreasing the PL efficiency. Our study presents a fundamental understanding of the PL properties of quantum-confined CsPbBr3 perovskites and may guide the development of the corresponding light-emitting devices.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2025
·
IF 6.7
Yang Feng,Yuxian Zhou,Xinyi Yang,Zili Huang,Jiaxi Hu,Yi Lv
With the growing demand for highly efficient sensors capable of rapid and reliable detection of trap states in semiconductors, developing novel chemical and physical phenomena induced by trap states at nanomaterial interfaces has thus emerged as a critical technological field. Herein, we developed an innovative time-dependent chemiluminescence (CL) method for evaluating trap states in semiconductor materials. By leveraging the unique trap states of Cr3+-activated zinc gallate (ZGOC) semiconductors and the hydroxyl radical (·OH)-rich EDTA-Fe2+-H2O2 system, we achived rational manipulation of ·OH-triggered time-dependent near-infrared (NIR) CL induction. To extract high-information-density outputs from the CL response, ZGOC nanocrystals associated with different Cr3+-related trap states were precisely identified by a distinct CL “fingerprint” pattern and robust statistical analysis. Remarkably, the generalizability of this method was validated using mixed models containing two typical samples and other adjustable ZGOC systems. The developed CL probe for Cr3+-related trap state evaluation provides advantages such as cost-effectiveness, operational simplicity, and rapid response, offering a promising and innovative alternative to conventional trap state assessment methods.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Xing-Liang Yin,Lei-Lei Li,Da-Cheng Li,Zhong-Jia Li,Yuan-Xu Wang,Xiang-Jin Kong,Jin-Sheng Zhao,Jian-Hua Jiang,Jun-Chao Qian,Dong-Hui Pang,Xin-Xin Du,Jian-Min Dou
Photocatalytic water splitting is considered to be a green H 2 generation approach and has potential to be applied in the future. As a photocatalytic active material for H 2 evolution, CdS is a good candidate. However, the pristine CdS still suffers from low efficiency and poor stability. To address those issues, we developed noble-metal-free CdS@MoS 2 core-shell nanoheterostructures which exhibit outstanding photocatalytic H 2 evolution performance thus far with rate of 62.55 mmol g −1 h −1 , which exceeds that of pristine CdS by a factor of 148. Meanwhile, the photocatalytic stability can be well retained with no deterioration of activity in 24 h reaction. The excellent performance can be reasonably attributed to the low crystallinity of MoS 2 with numerous active sites provided, and the band alignment of CdS and MoS 2 as determined by valence band-XPS and Mott-Schottky plots analysis, which significantly promotes charge transportation and separation. The enhanced photocatalytic stability here should be ascribed to the intimate growth of MoS 2 shells which significantly passivate the surface trap states of CdS cores and thus the photocorrosion is remarkably retarded. This novel strategy will inspire the fabrication of other photocatalytic systems, and may high-efficient photocatalysts be obtained.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Chao Tan,Weilong Liu,Wenzhuo Li,Hongbo Qi,Xiaojun Zhu,Zhongfang Ji,Jian Cheng,Wenzhi Wu,Qingxin Yang
Appropriately doped lead-free double perovskites (LFDPs) or vacancy-ordered double perovskites (VODPs) exhibit efficient and stable white-light emission via self-trapped excitons (STEs), and therefore hold significant potential for applications in lighting and display technologies. However, the intrinsic luminescence of the host is often disregarded when studying the doped materials because most LFDPs or VODPs possess indirect bandgaps or parity-forbidden transitions from conduction band to valence band. Here, we report a weak warm white light emission from pure Cs2SnCl6 microcrystals, and attribute this emission to the deep trap state according to the observations of absorption and photoluminescence (PL) spectra. The bandgap and structural characteristics of Cs2SnCl6 were further illustrated by analyzing the absorption, PL, Raman spectra and PL dynamics under variable pressure and temperature conditions. The emission mechanism of the deep trap levels in Cs2SnCl6 microcrystals and their potential impact on the STEs emission were discussed based on the spectroscopic observations.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Yuzhu Li,Zongbao Zhang,Yang Zhou,Lai Xie,Naitao Gao,Xubing Lu,Xingsen Gao,Jinwei Gao,Lingling Shui,Sujuan Wu,Junming Liu
Metal halide perovskite solar cells have drawn a lot of attention due to their excellent photovoltaic properties. However, a simple method to prepare perovskite films with high quality in ambient air remains a big challenge, which has become an obstacle for the commercialization of PSCs. Here we propose a facile method to prepare efficient CH 3 NH 3 PbI 3-x (SCN) x -based planar PSCs in ambient conditions and ammonium salts (NH 4 Cl, NH 4 SCN) are used to regulate the microstructure of CH 3 NH 3 PbI 3-x (SCN) x perovskite film prepared in ambient air. At the optimal concentration, the devices with NH 4 Cl or NH 4 SCN additives achieve the champion efficiency of 14.71% and 16.61% respectively, which are much higher than the 12.97% of the reference device. The stability of the unsealed devices with additives in ambient air has also been significantly improved. The modified devices without any encapsulation still retain about 80% of initial efficiency after 30 days in ambient air. The conductive atomic force microscopy and photoluminescence measurement are used to characterize photoelectric properties of perovskite film. The trap-state density and charge recombination of the devices have been investigated. The results suggest that the improved photovoltaic characteristics and stability may be attributed to the improved quality of perovskite films, the reduced trap states and the suppressed charge recombination.
研究领域:
材料科学
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能源技术
·
光伏器件
✓ 已验证
DOI
高影响因子
Materials Research Express
·
2017
·Vol. 4
·期 8
·085028
·
IF 1.068
Guangguang Huang,Chunlei Wang,Shuhong Xu,Yiping Cui
For ultrasmall Mn-doped quantum dots (QDs), the energy transfer of the exciton to the Mn is the key factor for Mn emission. Herein, the Ag-induced electron trap state energy level, which is an intermediate energy level between the conduction band (CB) and 4T1 of Mn, is proposed for improving the energy transfer. After doping the Ag and forming Ag&Mn:ZnInS QDs, most excitons will first be captured by the intermediate energy level and then be transferred to Mn d-states, leading to enhanced photoluminescence (PL) quantum yields (QY) of the QDs from the original 17% (Mn:ZnInS QDs) to 30% (Ag&Mn:ZnInS QDs).
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2024
·Vol. 26
·期 24
·17182-17190
·
IF 2.9
Zhe-Yong Chen,Xue Ren,Hui-Ling Hu,Meng Liu,Yi Liu,Feng-Lei Jiang
ZnSeTe quantum dots (QDs) attract growing interest owing to their low threats to health and the environment. They are widely applied as emitters in displays and lighting devices. Previous findings have indicated that inorganic halides are excellent candidates for surface ligands on QDs. By incorporating inorganic halides during the synthesis process, the photoluminescence (PL) intensity and quantum yield (QY) of QDs can be significantly enhanced. However, the alteration of surface states in QDs induced by zinc halide modification and the mechanism of formation of trap-state radiative recombination processes have been less discussed. Herein, we proposed a synthesis strategy for ZnSeTe/ZnSe/ZnSeS/ZnS core/shell/shell/shell QDs modified with ZnCl2, and by comparing the morphology and elemental composition of QDs with different amounts of ZnCl2 added, we revealed the regulatory mechanism of nanocrystal growth in the presence of ZnCl2. QDs with modification of ZnCl2 exhibited broad yellow fluorescence, distinct from the intrinsic blue emission. Through spectroscopic and surface ligand analyses, we attributed this yellow emission to the intermediate state energy levels caused by the defects on the surface. Finally, we used the QDs with broad linewidth emission to fabricate a simple white-light-emitting diode (WLED). This work provided new insights into the role of inorganic ligands and the use of a single emitting material in solid-state lighting devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 35
·2103978
·
IF 18.808
Wenchao Wang,Xueqin Bai,Qing Ci,Lili Du,Xingang Ren,David Lee Phillips
Undesired photoelectronic dormancy through active species decay is adverse to photoactivity enhancement. An insufficient extrinsic driving force leads to ultrafast deep charge trapping and photoactive species depopulation in carbon nitride (g-C 3 N 4 ). Excitation of shallow trapping in g-C 3 N 4 with long-lived excited states opens up the possibility of pursuing high-efficiency photocatalysis. Herein, a near-field-assisted model is constructed consisting of an In 2 O 3 -cube/g-C 3 N 4 heterojunction associated with ultrafast photodynamic coupling. This In 2 O 3 -cube-induced near-field assistance system provides catalytic “hot areas”, efficiently enhances the lifetimes of excited states and shallow trapping in g-C 3 N 4 and this favors an increased active species density. Optical simulations combined with time-resolved transient absorption spectroscopy shows there is a built-in charge transfer and the active species lifetimes are longer in the In 2 O 3 -cube/g-C 3 N 4 hybrid. Besides these properties, the estimated overpotential and interfacial kinetics of the In 2 O 3 -cube/g-C 3 N 4 hybrid co-promotes the liquid phase reaction and also helps in boosting the photocatalytic performance. The photocatalytic results exhibit a tremendous improvement (34-fold) for visible-light-driven hydrogen production. Near-field-assisted long-lived active species and the influences of trap states is a novel finding for enhancing (g-C 3 N 4 )-based photocatalytic performance.
研究领域:
材料科学
·
光催化
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 10
·3470-3476
·
IF 7.393
Yiwei Zhang,Fengjing Liu,Chao Jiang,Fawei Tang,Xinping Zhang
The robust material tunability of the hybrid organic–inorganic perovskite (HOIP) has attracted considerable research interests to explore the application in photoelectronic devices. Huge hysteresis has been recognised as a main problem in HOIP-based photoelectric devices; the origin of hysteresis has been attributed to the ion migration and trap states in HOIP materials. In this study, we designed and synthesised a HOIP single crystal with one-dimensional structure where the PbI42− octahedron is caged by the organic chains. The ion migration can be dramatically suppressed by the quantum size effect. Besides, in the single crystal trap states density is ultra-low due to the absence of grain boundaries. As a result, photodetectors based on this 1D HOIP single crystal show negligible hysteresis I–V curves. Moreover, a high quality ohmic contact is formed between electrodes and 1D HOIP, which is beneficial for photocarrier extraction. A responsivity of 80 mA W−1 and EQE of 30% are realised. The response speed is determined to be less than 0.4 ms. In addition, the photodetectors based on the novel 1D single crystal present good stability; after 3 months of ambient storage, 85% of its original photocurrent generation ability is retained.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
高影响因子
ORGANIC ELECTRONICS
·
2018
·
IF 3.68
Yue Wang,Lijie Zhu,Tiening Wang,Yufeng Hu,Zhenbo Deng,Qiuhong Cui,Zhidong Lou,Yanbing Hou,Feng Teng
In this work, we synthesized ligand-free anatase TiO 2 nanocrystals with clean surface and excellent electron extraction. By introducing the trap states between the TiO 2 nanocrystals and the photoactive layer of poly (3-hexylthiophene) (P3HT): (phenyl-C61-butyric-acid-methyl-ester) (PC 61 BM) bulk heterojunction (BHJ), a high performance solution-processed broadband OPD in the visible wavelength is realized and characterized. The OPD shows near spectrally flat response from 350 to 650 nm with high EQE (113%), high responsivity (0.5 A/W) and high detectivity (1.9 × 10 12 Jones) at −1 V. The device also exhibits a high −3 dB bandwidth of 902 kHz and a respectable response speed with a rise time and fall time of 34 μs and 26 μs, respectively. The photocurrent retention measurement at a bias voltage of −1 V implies that the device photoresponse is significantly stable. These OPD performance parameters are sufficient for use in the machine vision or imaging systems. With the help of the J-V curves and light assisted C-V measurements, the underlying working mechanism is proposed as well.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2022
·Vol. 18
·期 44
·2204120
·
IF 15.153
An Hu,Peng Bai,Yunke Zhu,Zhenyu Tang,Lixin Xiao,Yunan Gao
Colloidal semiconductor CdSe nanoplatelets (NPLs) feature ultranarrow and anisotropic emissions. However, the optical performance of blue-emitting NPLs is deteriorated by trap states, currently exhibiting tainted emissions and inferior photoluminescence quantum yields (PLQYs). Here, near trap-free blue-emitting NPLs are achieved by the controlled growth of the core/crown. Deep trap states in NPLs can be partially suppressed with the asymmetrical crown growth and are further suppressed with the growth of the small core and the alloyed symmetrical crown, yielding NPLs with pure blue emissions and near-unity PLQYs. Exciton dynamic research based on these NPLs indicates that the trap emission stems from surface traps. Besides, light-emitting diodes exhibiting ultranarrow emission centered around 461 nm with full-width-at-half-maximums down to 11 nm are fabricated using these NPLs.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）