ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 19
·56188-56197
·
IF 5.8
Chen Jingwen,Wu Menglin,Ni Jiupai,Ni Chengsheng
Photocatalysis using the visible light of the sun is an environmentally friendly method of eliminating the NOx pollutant from the ambient air. Although Cs 3 Bi 2 Br 9 , a semiconductor with a band gap of 2.54 eV, may be a strong absorber of visible light, its photocatalysis towards the abatement of NOx is unknown. In this study, Cs 3 Bi 2-x Pb x Br 9-x (0 ≤ x ≤ 0.0789) are used for the photocatalytic oxidation of NOx. A significant NO oxidation efficiency (80%) is observed over Cs 3 Bi 2-x Pb x Br 9-x (x = 0.0443) under visible light, which is attributable to the Br vacancy ( V Br ) brought about by Pb 2+ doping. The presence of V Br increased the ionic selectivity of in the oxidized NO. At higher Pb doping level, two HONOs adsorbed on the V Br , linked, and then reduced by hot electrons to produce N 2 O 2 2− . The di-azo coupling could passivate the activation of NO on the V Br . This work advances the defect engineering of halide for the photo-driving solid–gas reaction in air.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
PubMed
高影响因子
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
·
2022
·Vol. 37
·期 6
·065011
·
IF 2.048
Xiaoyu Wang,Nasir Ali,Gang Bi,Huizhen Wu
In this work, lead-free double perovskite Cs2BiAgBr6 film is fabricated and employed into resistive switching (RS) memory device with a metal/insulator/metal structure. The RS performances of the prepared device are examined both experimentally and theoretically. High-quality Cs2BiAgBr6 film is fabricated via a post-vacuum treatment and characterized systematically. In the prepared memory device, bipolar RS is observed with a high ON/OFF ratio, and the retention and endurance performances are measured. First-principles calculations based on the density functional theory reveal that the bromide vacancies (VBr) in Cs2BiAgBr6 render it metallic characteristics. Therefore, we propose that the migration of VBr under electrical fields formed and ruptured the conductive filament, leading to the RS behaviors of memory device.
研究领域:
材料科学
·
计算物理
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DOI
高影响因子
Laser & Photonics Reviews
·
2024
·
IF 9.8
Xuemin Wen,Maksym Buryi,Vladimir Babin,David John,Romana Kučerková,Martin Nikl,Qian Wang,Yunyun Li,Wen Li,Fan Yang,Xiaoping OuYang,Yuntao Wu
The development of ultrafast scintillators is critical to the GHz X-ray and time-of-flight (TOF) imaging techniques. Low-dimensional silver-based halides have emerged as promising candidates due to high radioluminescence efficiency and ultrafast decay time. However, the ultrafast scintillation mechanism in silver-based halides, such as Rb 2 AgBr 3 (RAB), remains controversial. Here, the study reveals the origin of ultrafast scintillation timing response in melt-grown RAB bulk crystals. The RAB shows light-yellow emission with a photoluminescence quantum yield (PLQY) of 13.9%. Under the picosecond (ps) pulse X-ray irradiation, RAB has an ultrafast decay time of 3.2 ns that accounts for 40.5% of the total emitted light. The light yield is estimated as 3100 photons MeV −1 under 22 Na irradiation. Based on the temperature-dependent radioluminescence (RL) spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and spectrally resolved thermally-stimulated luminescence (TSL) glow curves, it is confirmed that the bromine vacancy as the F-center is the origin of the ultrafast scintillation component. These findings provide elaborated and fundamental insights into the ultrafast luminescent mechanisms of low-dimensional silver-based halides, thereby opening up new design horizons in the development of ultrafast scintillators.
研究领域:
材料科学
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光学
·
辐射探测
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DOI
高影响因子
Small Structures
·
2024
·Vol. 5
·期 7
·2300577
·
IF 13.9
Feiyu Diao,Qingye Zhang,Jiaju Wang,Wenshuang Liang,Federico Rosei,Xuyan Xue,Yiqian Wang
All-inorganic halide perovskites exhibit exceptional optical properties and are promising photoactive materials for optoelectronics. However, their stability remains a key challenge, exacerbated by a limited understanding of degradation mechanisms. Herein, in situ transmission electron microscopy (TEM) is used to investigate the effect of thickness on the structural stability of CsPbBr 3 nanobricks under electron beam irradiation. CsPbBr 3 nanobricks with different thicknesses have been prepared using a traditional hot-injection method, giving rise to a distinctive cubic structure. A modulated structure, caused by bromine vacancy ordering, has been observed in the thin nanobricks. The degradation behaviors of nanobricks are related to thickness-dependent bromine vacancy formation in the CsPbBr 3 lattice. More bromine vacancies exist in thin nanobricks than thick ones, resulting in a greater number of undercoordinated Pb atoms which accelerate irradiation-induced degradation. Decomposition products include Pb nanoparticles, which also demonstrate thickness-dependent characteristics. TEM images of Pb nanoparticles formed from thin nanobricks show evidence of irradiation-induced amorphization. In thicker nanobricks, Pb nanoparticle size increases with the duration of electron beam irradiation, while the remaining Cs atoms bond with Br atoms to form relatively stable CsBr nanoparticles. These results contribute to understanding of degradation mechanisms in cesium lead halide perovskites under electron beam irradiation.
研究领域:
材料科学
·
物理学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Feiyang Zhang,Penglei Xu,Xueqing Jin,Chen Wang,Qi Shen,Chunyan Sun
Polybrominated diphenyl ethers (PBDEs) have attracted increasing attention due to their biotoxicity and persistence. Herein, rapid degradation of decabromodiphenyl ether (BDE209) was achieved on bromine vacancies enriched BiOBr (BOB-V Br ) nanosheets, with a degradation rate for BDE209 under visible light irradiation (λ > 400 nm) exceeding 95 % within 6 min. The initial two minutes serve as an induction period, during which the Br vacancies were in-situ introduced into the BiOBr (BOB) nanosheets. By precisely controlling the duration of photoinduction, varying concentrations of Br vacancies were successfully generated on the surface of the BOB nanosheets. Consequently, an enhanced degradation rate of BDE209 was observed in direct correlation with the increased concentration of Br vacancies. BOB-V Br showed a remarkable selectivity of 74 % for meta- product (BDE207). This selectivity towards BDE207 surpasses that of other anionic vacancies, as oxygen, sulfur, and iodine vacancies. The in-situ generated Br vacancies help to accommodate the Br atom of BDE209 in atomic size and electronic structure, thus facilitating the activation of the C-Br bond and achieving rapid BDE209 debromination. This work provides a new insight for the treatment of organic halogenated pollutants by photocatalysts with homologous halogen vacancies.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
Advanced Electronic Materials
·
2019
·Vol. 6
·期 2
·1900754
·
IF 6.312
Yuanyuan Zhu,Pengwei Cheng,Jing Shi,Hongjun Wang,Yong Liu,Rui Xiong,Hongyu Ma,Hongxiang Ma
All-inorganic halide perovskites have attracted a great deal of attention for applications in resistive switching (RS) memory devices due to their superior stability compared to organic–inorganic hybrid halide perovskites. RS memory devices utilizing air-stable all-inorganic halide perovskite cesium lead bromide (CsPbBr 3 ) film as the switching layer, which are successfully prepared by spin coating at low temperature, are demonstrated. Memory devices based on CsPbBr 3 film exhibit typical reproducible bipolar RS behavior and superior switching characteristics, including the high ON/OFF ratio (≈10 4 ), long data retention (>5 × 10 4 s), and environmental stability. In addition, multilevel storage capability can be achieved through controlling the different compliance currents. The formation and rupture of bromine (Br) vacancy conducting filaments (CFs) is proposed to explain the switching behavior in the Pt-anode-based memory devices, which is verified by XPS depth-profiling analysis. Moreover, the coexistence of Br vacancies and Ag metallic CFs is suggested to be responsible for the switching behavior in Ag-anode based device. These results demonstrate that the all-inorganic halide perovskite CsPbBr 3 film will be the promising switching material for nonvolatile memory devices.
研究领域:
材料科学
·
电子工程
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物理化学
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产品关联
DOI
高影响因子
Advanced Science
·
2022
·Vol. 9
·期 33
·2204138
·
IF 17.521
Cuiling Zhang,Chong Liu,Yanyan Gao,Shusheng Zhu,Fang Chen,Boyuan Huang,Yi Xie,Yaqing Liu,Mengen Ma,Zhen Wang,Shaohang Wu,Ruud E. I. Schropp,Yaohua Mai
Indoor photovoltaics (IPVs) are expected to power the Internet of Things ecosystem, which is attracting ever-increasing attention as part of the rapidly developing distributed communications and electronics technology. The power conversion efficiency of IPVs strongly depends on the match between typical indoor light spectra and the band gap of the light absorbing layer. Therefore, band-gap tunable materials, such as metal-halide perovskites, are specifically promising candidates for approaching the indoor illumination efficiency limit of ∼56%. However, perovskite materials with ideal band gap for indoor application generally contain high bromine (Br) contents, causing inferior open-circuit voltage ( V OC ). By fabricating a series of wide-bandgap perovskites (Cs 0.17 FA 0.83 PbI 3− x Br x , 0.6 ≤ x ≤ 1.6) with varying Br contents and related band gaps, it is found that, the high Br vacancy (V Br ) defect density is a significant reason that leading to large V OC deficits apart from the well-accepted halide segregation. The introduction of I-rich alkali metal small-molecule compounds is demonstrated to suppress the V Br and increase the V OC of perovskite IPVs up to 1.05 V under 1000 lux light-emitting diode illumination, one of the highest V OC values reported so far. More importantly, the modules are sent for independent certification and have gained a record efficiency of 36.36%.
研究领域:
材料科学
·
能源技术
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产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2024
·Vol. 11
·期 14
·4424-4431
·
IF 6.1
Jiaqi Zhao,Yuan Wang,Tinglei Wang,Yu Wang
Chiral defect-induced strategy is employed to synthesize zero-dimensional (0D) chiral Cs4PbBr6 perovskite nanocrystals (NCs) with blue photoluminescence via a phase transition process. The chirality of the ground state of chiral Cs4PbBr6 perovskite NCs is confirmed by circular dichroism (CD) spectra, which shows the characteristic mirrored CD signals, behaving as a pair of enantiomers. Meanwhile, the obvious circularly polarized luminescence (CPL) response indicates that the chiral Cs4PbBr6 perovskite NCs are endowed with the chirality of the excited state. Furthermore, the UV–vis spectroscopy and electron paramagnetic resonance (EPR) data explicitly reveal that the CPL response originates from the chiral bromine vacancy (VBr). This work not only provides guidance to realize the CPL of 0D chiral perovskites but also gives insights into the structure–property relationship.
研究领域:
材料科学
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光学
·
物理化学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Haoqi Li,Wenjun Yuan,Kun Zhang,Yifei Wang,Xinrui Chen,Yuqin Su,Xingle Shang,Hengyang Xiang,Haibo Zeng
The carrier injection limitation caused by the surface ligands of quantum dots (QDs) is a major challenge for achieving high-brightness emission in quantum dot light-emitting diodes (QLEDs). In this work, we enhanced the polarity of the antisolvent by incorporating inorganic bromides (ZnBr2) to improve ligand stripping capability, thereby achieving fewer insulating ligands to meet the demand for efficient carrier injection. Simultaneously, the inorganic bromide provided a Br-rich environment, suppressing the generation of Br vacancies under polar conditions, which frequently happened in traditional antisolvent strategies. Benefiting from this polarization-passivation synergistic strategy, ZnBr2-treated QDs exhibited a 17% reduction in ligand quantity and a 40% reduction in defect density, thus the photoluminescence quantum yield (PLQY) of ZnBr2-treated QDs increased from 47% to 86%. The fabricated QLEDs exhibited a 143% increase in current density and a maximum brightness reaching 104,126 cd/m2, which was 4.96 times that of samples treated with pure antisolvent. Correspondingly, the operational lifetime (T50@100 cd/m2) of the device extended from 20 h to 241 h. This simple inorganic bromide polarization-passivation synergistic strategy in QDs' purification engineering provides a new approach for realizing high-brightness QLEDs.
研究领域:
材料科学
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纳米科技
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光电功能材料
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半导体器件
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固态照明
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2021
·Vol. 33
·期 24
·2100674
·
IF 30.849
Wen Ye,Jing-Hui He,Qiang Cao,Wu-Ji Sun,Jia Wang,Ze-Kun Chen,Xue-Feng Cheng,Chuang Yu,Jian-Mei Lu
Owing to their special photoelectric properties, halide perovskites have always attracted research attention. Hollow-structured halide perovskites have many practical applications but are challenging to prepare as most template methods violate their poor chemical and thermal stability. In this study, novel halide perovskite Cs 2 PdBr 6 hollow nanospheres are prepared using a template-free method; specifically, large quantities of highly pure lead-free halide perovskite Cs 2 PdBr 6 hollow nanospheres are produced at 30 °C without a surfactant. These ultrapure nanospheres exhibit superiority in chemresistive detection of CO with a detection limit of 50 ppb, which is the lowest among all the reported CO sensing materials. Moreover, in situ sum-frequency-generation spectra and density functional theory calculations reveal that the high sensitivity is attributable to the large specific surface area and surfactant-free surface of rich Br − vacancies that favor CO binding. Overall, this work provides insight on regulation of the halide perovskite structure and the use of hollow spheres in gas-sensing applications.
研究领域:
材料科学
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纳米技术
·
气体传感
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钙钛矿化学
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环境监测
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Juan Gao,Qin Gao,Jiangshun Huang,Xueli Geng,Pengzhan Li,Yihang Liu,Qiaofeng Yang,Hao Zhang,Mei Wang,Zhisong Xiao,Paul K. Chu,Ruifeng Lu,Anping Huang
Low-power and color-sensitive neuromorphic vision systems are critical to the next generation of intelligent devices. Here, we report a coral-inspired, lead-free synaptic device based on Cs3Bi2Br9 perovskite nanocrystals prepared by centrifugal casting into a porous thin film. The device exhibits wavelength-dependent plasticity under 405, 520, and 635 nm illumination without an external bias. By modulating the light wavelength and intensity, short-term and long-term synaptic plasticity are achieved to mimic excitatory, inhibitory, and saturating biological responses. Structural and spectroscopic analyses reveal that bromine vacancies play a key role in the dynamic modulation of carrier transport and plasticity evolution. The efficient preprocessing of RGB visual information significantly enhances recognition accuracy in artificial neural network devices. This wavelength-specific modulation of synaptic plasticity, a novel approach for color image preprocessing and recognition, is very promising for the advancement of neuromorphic systems.
研究领域:
神经形态工程
·
光电子学
·
材料科学
·
人工智能硬件
·
光子学
✓ 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）