JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Ye Zhang,Xue Lou,Xiaochun Chi,Quan Wang,Ning Sui,Zhihui Kang,Qiang Zhou,Hanzhuang Zhang,Li Li,Yinghui Wang
The temperature-dependent time-resolved spectroscopies are employed to investigate the hot carrier characteristics in MAPbBr 3 nanocrystals (NCs). Simultaneously, the absorption and photoluminescence data exhibits that MAPbBr 3 NCs pass through cubic phase and tetragonal phase in turn as the temperature drops. As the phase transition from the cubic phase to the tetragonal phase, the band gap narrows, the shallow defects population that participates in the carrier dynamics and the Longitudinal-optical phonon energy ( E LO ) decreases. We uncovered that the hot carrier can be induced in the MAPbBr 3 NCs through changing the photon flux and the temperature. Moreover, the hot carrier cooling time and the carrier heating effect in tetragonal phase improved in comparison with those in cubic phase, owing to the influence of bandgap, shallow defect and E LO as mentioned above. These results can help us to further understand the hot carrier characteristics in the perovskite MAPbBr 3 NCs for designing and optimizing the perovskite-based optoelectronic devices of high performance.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 24
·2041
·
IF 4.4
Yi Zhang,Huilong Chen,Junfeng Qu,Jiayu Zhang,Gavin Conibeer
The hot carrier multi-junction solar cell (HCMJC) is an advanced-concept solar cell with a theoretical efficiency greater than 65%. It combines the advantages of hot carrier solar cells and multi-junction solar cells with higher power conversion efficiency (PCE). The thermalization coefficient (Qth) has been shown to slow down by an order of magnitude in low-dimensional structures, which will significantly improve PCE. However, there have been no studies calculating theQthof MAPbBr3quantum dots so far. In this work, theQthvalues of MAPbBr3quantum dots and after BABr addition were calculated based on power-dependent steady-state photoluminescence (PD-SSPL). Their peak positions in PD-SSPL increased from 2.37 to 2.71 eV after adding BABr. The fitting shows that, after adding BABr, theQthdecreased from 2.64 ± 0.29 mW·K−1·cm−2to 2.36 ± 0.25 mW·K−1·cm−2, indicating a lower relaxation rate. This is because BABr passivates surface defects, slowing down the carrier thermalization process. This work lays the foundation for the theoretical framework combining perovskite materials, which suggests that the appropriate passivation of BABr has the potential to further reduceQthand make MAPbBr3QDs with BABr modified more suitable as the top absorption layer of HCMJCs.
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
Advanced Optical Materials
·
2024
·
IF 8
Peipei Ma,Jinhai Si,Lihe Yan,Jiayi Wu,Jin Xu,Xun Hou
In semiconductor-based microlasers, the generated excited carriers can affect both the optical absorption coefficient and refractive index, influencing the lasing behavior and device performance. In this study, the lasing behavior of individual MAPbBr 3 microrods pumped by femtosecond laser pulses is investigated using an ultrafast optical Kerr gating technique. By analyzing the spectral and temporal evolution of the lasing behavior, it is found that the band-filling (BF) effect can cause a significant change in the refractive index of the material, which results in an unfavorable red-shift and broadening of the resonant modes, deteriorating the laser linewidth and quality factor. The hot carrier cooling process can provide a buffer for alteration of the energy level occupation state, resulting in a small transient refractive index change and slight red-shift. These results offer insights into the lasing behavior driven by photogenerated carrier dynamics and provide an optimization strategy for semiconductor-based microlasers.
研究领域:
光学
·
材料科学
·
半导体物理
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Guanhua Zhang,Tiantian Dai,Yue Meng,Lianyang Zhang,Chao Yang,Guoxiang Pan,Zheming Ni,Shengjie Xia
Z-scheme heterojunction catalysts are novel photocatalytic materials with wide application prospects because of their promise for the engineering of band structure to achieve high-speed hot carrier-transfer and strong redox tunability. A bridged-Au Z-scheme heterojunction catalyst (ZnO-Au-ZnAl 2 O 4 ) was synthesized using layered double hydroxides (LDHs) as the backbone. The atomistic and architectural structures, elemental composition and and visible-light absorption of as-prepared photocatalysts were systematically investigated and characterized. The presence of Z-scheme heterojunctions in ZnO-Au-ZnAl 2 O 4 can significantly improve the photocatalytic activity under visible light irradiation with a reaction rate constant of 0.5503 h −1 (ZnO-Au(2%)-ZnAl 2 O 4 ), 27.2 times that of pure ZnO (0.0202 h −1 ) and 9.8 times that of ZnO-ZnAl 2 O 4 (0.0389 h −1 ). We further investigated the reaction kinetics of the heterostructure catalyst in the photodegradation of catechol , where the effect of the catalyst dosage, initial pH, irradiation intensity and reaction temperature were discussed. Based on the mechanism study in the capture and detection of photo-generated radicals and the calculation of band structures by DFT (work function), the successful construction of bridged-Au Z-scheme heterojunction was further proven. Au nanoparticles sandwiched between ZnO and ZnAl 2 O 4 play a vital role for the formation of a built-in electric field (BIEF) between ZnO and ZnAl 2 O 4 , which can significantly facilitate the transfer of hot carriers in the photocatalytic system.
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
GREEN CHEMISTRY
·
2023
·Vol. 25
·期 7
·2771-2781
·
IF 9.8
Pei-dong Wu,Lanyun Li,Keping Wang,Hu Li,Zhen Fang
A photoelectrochemical system is a promising method for biomass valorization but is still in its infancy. Herein, a Mo–BVO–TiCoNO–CoFeOxy photoanode with a nanowire structure was prepared for the first time to efficiently convert bio-based benzyl alcohol (BA) to benzoic acid (97.7% yield) in water while coupling H2 production of 136.8 μmol cm−2. The nanowire structure enables a significant increase in the exposed active sites on the photoelectrode surface to enhance the BA oxidation capacity, whereas its large aspect ratio increases visible light absorption, and the thermal effect (resulting from the size effect) increases H2 production at the counter electrode. DFT calculations and further experiments revealed that Co species of the CoFeOxy layer functioned as stabilizers of photoelectrode properties, while Fe species acted as catalytic site providers in the BA oxidation. The analysis of steady-state photoluminescence with variable temperature showed the generation of hot carriers and conversion to photocurrent over the non-noble bimetallic material.
研究领域:
材料科学
·
光化学催化
·
能源转化
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2020
·Vol. 31
·期 6
·2005688
·
IF 16.836
Bin Zeng,Shengyang Wang,Yuying Gao,Guanna Li,Wenming Tian,Jittima Meeprasert,Hao Li,Huichen Xie,Fengtao Fan,Rengui Li,Can Li
Plasmon-induced photocatalysts hold great promise for solar energy conversion owing to their strong light-harvesting ability and tunable optical properties. However, the complex process of interfacial extraction of hot carriers and the roles of metal/semiconductor interfaces in plasmonic photocatalysts are still not clearly understood. Herein, the manipulation of the interface between a plasmon metal (Au) and a semiconductor (rutile TiO 2 ) by introducing an interfacial metal oxide (Al 2 O 3 ) is reported. The resulting Au/Al 2 O 3 /TiO 2 exhibits remarkable enhancement in photocatalytic water oxidation activity compared with Au/TiO 2 , giving an apparent quantum efficiency exceeding 1.3% at 520 nm for photocatalytic water oxidation. Such an interfacial modulation approach significantly prolongs the lifetime of hot carriers in the Au/TiO 2 system, which conclusively improves the utilization of hot carriers for plasmon-induced water oxidation reaction upon irradiation. This work emphasizes the essential role of the interfacial structure in plasmonic devices and provides an alternative method for designing efficient plasmonic photocatalysts for solar energy conversion.
研究领域:
材料科学
·
能源转换
·
表面化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Jin-Feng Liao,Yang-Fan Xu,Xu-Dong Wang,Hong-Yan Chen,Dai-Bin Kuang
Though coating CsPbBr3 nanocrystal (NC) with an outer layer has been regarded as an effective strategy to address its instability issues, deep investigations into the electronic interaction between CsPbBr3 NC and coating layer have yet to be conducted. In this study, the dynamics of hot carrier and charge carrier of CsPbBr3 nanocrystal with various MO2 (M = Si, Ti, Sn) coating layers have been comprehensively studied. Combined transient optical characterizations (time-resolved photoluminescence and ultrafast transient absorption) and photoelectrochemical measurements reveal that coating with insulating SiO2 accelerates the hot carrier relaxation and enhances the radiative recombination by passivating surface traps, whereas efficient charge-carrier separation and extraction are observed after coating with SnO2 and TiO2. The electron injection from CsPbBr3 NC to SnO2 (1.14 × 108 s–1) is 2-fold faster than to TiO2 (5.4 × 107 s–1) owing to the lower conduction band edge and the higher electron mobility of SnO2. Particularly, the first time fabricated CsPbBr3 NC/SnO2 composite exhibits superior stability against UV light and moisture, as well as the best photocurrent response in this study. This work has implied that rational design of the coating layer for perovskite NC can not only improve the stability but also tailor the electronic and optoelectronic properties for various applications.
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
Journal of Physical Chemistry C
·
2022
·
IF 4.177
Shu Hu,Yongtao Huang,Yang Zhang,Pingyuan Yan,Heng Li,ChuanXiang Sheng
Significantly slow hot-carrier-cooling happens in a multiphase quasi two-dimensional (2D) perovskite film of (BA)2(FA)n−1PbnI3n+1, where BA is butylammonium, FA is formamidinium, and n = 3 nominally. Due to this phenomenon, a linearly polarized multi-peak emission from phases of n = 2, 3, and 4 emerges and the ever-present one from n = ∞ phase blue-shifts in the photoluminescence (PL) spectra, excited using a nanosecond pulsed laser with increasing excitation intensities. Furthermore, hot-carrier PL from small n materials also emerges using a continuous wave laser with an intensity of ∼100 mW/cm2; consequently, the abnormal enhancement of the open-circuit voltage through hot-carrier extraction above 300 mW/cm2 is achieved. Our work may prove that the FA-based 2D perovskite gives a direction to fabricating hot-carrier solar cells that potentially boost the power conversion efficiency.
研究领域:
材料科学
·
光伏技术
·
物理化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Min Xu,Peng Wang,Shuwen Qi,Rongjun Zhao,Lin Xie,Yong Hua
Enhancing the efficiency and stability is very critical for perovskite solar cells (PSCs) commercialization. Herein, we report an effective approach to enable highly efficient and stable PSCs by incorporating a polymer material, poly[N, N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene) (named P(NDI2OD-T2)), into hole transport layer (HTL). Our research results exhibit that the addition of P(NDI2OD-T2) not only effectively improves the hole mobility and conductivity of HTL, but also makes its energy level more alignment with perovskite. More importantly, ultrafast carrier results demonstrate that the introduction of P(NDI2OD-T2) into Spiro-OMeTAD HTL can effectively improve the extraction and transfer of hot carriers from perovskite layer to HTL, and consequently reduce the recombination of charge carriers in the device. As a result, PSCs based on Spiro + P(NDI2OD-T2) as a HTL shows an enhanced power conversion efficiency (PCE) of 24.20 %, which is much higher than that of control device without P(NDI2OD-T2) (21.94 %). Furthermore, the un-encapsulated P(NDI2OD-T2)-treated PSCs exhibit excellent humidity, thermal and light stabilities, with the devices maintaining 94 % of its initial efficiency after 3000 h at ≈40 % humidity, 95 % of its initial efficiency after storage at 65 °C and 85 °C for 600 h, and 90 % of its initial efficiency after 600 h under one sun light irradiation, respectively. This work provides an effective strategy for improving the device efficiency and long-term stability of PSCs.
研究领域:
材料科学
·
能源技术
·
光物理化学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2025
·
IF 3.4
Jingsong Liu,Songyao Wu,Zhe Dong,Meizi Yang,Fengyuan Zhang,Guowei Li,Hangyu Yan,Mengdai Luoshan
Multicomponent heterojunctions have attracted considerable attention for the potential applications in photodriving applications. However, the limited number of active sites on the surface and the rapid recombination of photogenerated carriers restrict the improvement of the performance of photothermal conversion and photocatalytic degradation. Here, a ternary nanohybrid composed of PbS, Pt, and TiO2 is presented for the first time. PbS nanocrystals evolved from octahedral to a unique 24-faceted morphology were monitored and described systematically. Then, they were selectively deposited by Pt nanoparticles and coated with a TiO2 thin nanoshell. Under 808 nm near-infrared laser irradiation, the photothermal conversion performance and photocatalytic reduction rates of these nanohybrids were investigated in depth. Among them, the PbS-Pt-TiO2 nanohybrids exhibited the highest photothermal conversion efficiency and fastest degradation speed of Rhodamine B when compared to PbS-Pt and pure PbS, which are attributed to the effective light absorption of 24-faceted PbS nanocrystals and the outer TiO2 shell, the abundant catalytic active sites provided by Pt nanoparticles, and the excellent separation and transportation efficiency of hot carriers between different components.
研究领域:
纳米材料
·
光催化
·
能量转换
·
材料科学
·
光学材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Photonics
·
2024
·
IF 6.5
Shulin Sha,Kai Tang,Maosheng Liu,Peng Wan,Zeng Liu,Da Ning Shi,Caixia Kan,Mingming Jiang
Ferroelectric materials, known for their superior spontaneous polarization and pyroelectric and photovoltaic effects, offer a promising avenue for fabricating high-performance optoelectronic devices. Herein, we report an ultraviolet (UV) photodetector (PDs) based on BaTiO3@MXene/4H-SiC heterostructure, with its photosensitive properties significantly boosted by the ferro-pyro-phototronic effect. In the detector, the incorporation of MXene nanosheets boosts the spontaneous ferroelectric polarization of BaTiO3 nanocrystals, thereby strengthening the built-in electric field at the BaTiO3/4H-SiC heterojunction. The resulted BaTiO3@MXene/4H-SiC heterostructure can work in a self-biasing manner, with robust performances, including responsivity (∼187.74 mA/W), specific detectivity (∼6.52 × 1013 Jones), external quantum efficiency (∼75.07%), response/recovery time (∼74.3/122.7 μs) upon 310 nm light irradiation. Particularly, the superlinear increase of the photocurrent, which results from the hot-carrier multiplication in MXene nanosheets, allows the device to produce additional photocurrent under ultraviolet illumination. Theoretical analysis confirms that the surface modification of MXene nanosheets can effectively alter the length of the Ti–O bonds on BaTiO3 nanocrystal surfaces, thus enhancing their spontaneous ferroelectric polarization. Being seamlessly integrated into an ultraviolet wireless communication system, the BaTiO3@MXene/4H-SiC self-powered photodetector demonstrates promising application prospects in optoelectronic interconnection circuits. This study provides an optimization strategy for advanced BaTiO3 nanocrystals toward future high-performance electronic and optoelectronic devices in existing applications.
研究领域:
材料科学
·
光电子学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2016
·
IF 4.712
Xiang Wei,Zhonghui Liu,Xiulong Jin,Lin Huang,Deepanjali Dattatray Gurav,Xuming Sun,Baohong Liu,Jian Ye,Kun Qian
Laser desorption/ionization mass spectrometry (LDI MS)-based small metabolites detection is fundamentally important for the clinic prognoses and diagnoses. Plasmonic materials have been applied as efficient substrates for LDI MS of these molecules. However, there is no clear understanding of the mechanism of using plasmonic materials for enhanced LDI MS of small metabolites, thus restricting their application for real case serum samples. In this work, we report the use of plasmonic nanoshells for enhanced LDI MS detection of small analytes. The antibonding modes of Au nanoshells provided unique opportunity for the generation of hot carriers in the ultra-violet (UV) optical range. This effect of the Au nanoshells displayed desirable analytical sensitivity and endurance towards small metabolites (e.g. amino acids) in complex protein/mixtures as compared to Au nanorods/nanospheres and conventional organic matrix. Further we achieved LDI MS profiling and detection of small metabolites from complex serum samples by Au nanoshells. Our work not only shed light on the enhancement mechanism of LDI MS detection using plasmonic nanoparticles with hot carriers, but also contributed to the real case application of LDI MS in clinical study.
研究领域:
分析化学
·
医学诊断
·
纳米生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）