CRYSTENGCOMM
·
2024
·Vol. 26
·期 27
·3726-3735
·
IF 2.6
Tianfeng Li,Xingyi He,Zifan Liang,Yingxin Dong,Renming Liu,Zhen Chi,Yanmin Kuang,Xiaojuan Wang,Lijun Guo
The emission of cyan light (470–500 nm), an essential component of the visible light spectrum, plays a crucial role in lighting, display, and light communication. CsPbBr3 quantum dots (QDs) have shown excellent performance in the green spectral regions, with high color purity, efficiency, and brightness. In order to shift the emission wavelength to the cyan, mixed-halide compositions and quantum-confinement engineering have been employed. Unfortunately, mixed-halide perovskites exhibit undesirable phase separation during optical and electrical excitations, leading to spectral instability. Quantum confinement in pure-halide QDs requires synthetic protocols that involve high loading of long-chain insulating ligands. In this study, we report color-stable cyan CsPbBr3 quantum dots (C-PQDs) by surface passivation via incorporating Zn2+ cations. The incorporation of ZnBr2 into the precursor solution facilitates Zn2+ and Br− substitution into the QDs surface/subsurface layers to induce passivation of existing Pb2+ and Br− vacancies and increase the photoluminescence quantum yield from 53.6% to 96.4% at 480 nm. Moreover, after storage under ambient conditions for 30 days or exposure to ultraviolet light for 60 minutes or heating at 333 K, the PL intensity of ZnBr2-treated C-PQDs only shows a minimal decrease. Furthermore, white and cyan light-emitting diodes (LEDs) are successfully constructed, suggesting that the proposed ZnBr2-treated strategy can promote the development of perovskite materials for a wider range of optoelectronic applications.
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
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Huijun Liu,Ying Mo,Mengjuan Sun,Qingqing Zhu,Zhongping Huang,Jian Shen
A method for the determination of brominated flame retardants was established by micro sample pretreatment technology combined with ion chromatography. Using a sealed glass capillary as a micro reactor, the brominated flame retardants were debrominated by pyrolysis at 300 ℃ and absorbed by absorbing liquid, followed by ion chromatography determination. To improve the debromination efficiency, important factors including pyrolysis time and absorbing liquid were investigated. The linearity of the method was satisfactory over a Br − concentration of 0.05–100 mg/L and the determination coefficient was greater than 0.999. The limit of detection and limit of quantitation of bromide ion were 1.50 μg/L and 5.00 μg/L, respectively. The potential of the established method was assessed by applying it to the determination of total bromine in actual electrical and electronic equipment. The average recoveries (97.1–104.2 %) and the precision (3.1–7.5 %) were achieved by real samples spiked with three levels. This proposed method, with simple operation and low cost, could be a good supplementary for the oxygen bomb combustion-ion chromatography method for the determination of brominated flame retardants in electrical and electronic products.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Huafeng Li,Jin Wang,Rui Wang,Kaibo Huang,Wanying Luo,Xueqin Tao,Zhi Dang,Hua Yin,Chuling Guo,Guining Lu
Polybrominated diphenyl ethers (PBDEs) belong to a class of persistent organic pollutants (POPs), with potential toxicity to the liver, reproductive system, and development of mammals. The highly toxic and concentrated congener, 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47), was chosen to investigate debromination mechanisms by the two synthetic iron-based bimetals (Pd/Fe 0 and Cu/Fe 0 ) in two protic solvents (water and ethanol). SEM, XPS, and BET analyses showed that the synthetic bimetals Pd/Fe 0 and Cu/Fe 0 were spherical with diameters of about 100 nm and loaded with ∼1% (wt%) of Pd and Cu, respectively. GC-MS was used for the analysis of degradation products and the chromatograms showed that both Pd/Fe 0 and Cu/Fe 0 bimetals had effective reducing properties in water solvent. In ethanol solvent, debromination of BDE-47 by Pd/Fe 0 showed a similar high activity, but BDE-47 could be hardly degraded by Cu/Fe 0 . The dominant debromination products of BDE-47 by Pd/Fe 0 and Cu/Fe 0 were ortho -substituted and para -substituted BDEs, respectively. Active H-atomic transfer was found to play a key role in the debromination of BDE-47 by Pd/Fe 0 in both, water and ethanol, with a preference for para -debromination along with the formation of dibenzo-p-furan (DF) as the by-product, mainly in water. In contrast, electron transfer with a preference for ortho -debromination was found to play a predominant role for Cu/Fe 0 system in water. More importance should be provided to active H-atomic transfer for its high efficiency. In-depth study on the mechanism of formation of by-product DF would be significant for its higher toxicity, possibility of accumulation and migration in the environment.
研究领域:
环境科学
·
毒理学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 4
·914
·
IF 3.267
Ligeng Wang,Chun Feng,Yan Zhang,Jun Hu
The regioselective mono-bromination of phenols has been successfully developed with KBr and ZnAl–BrO3−–layered double hydroxides (abbreviated as ZnAl–BrO3−–LDHs) as brominating reagents. The para site is much favorable and the ortho site takes the priority if para site is occupied. This reaction featured with excellent regioselectivity, cheap brominating reagents, mild reaction condition, high atom economy, broad substrate scope, and provided an efficient method to synthesize bromophenols.Keywords:phenol;bromination;regioselecitvity
研究领域:
有机化学
·
材料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Zongtang Liu,Haini Yang,Mian Wang,Yufeng Sun,Zhenghao Fei,Shujuan Chen,Rui Luo,Lin Hu,Chenggang Gu
Effective removal of polybrominated diphenyl ethers (PBDEs) from the environment is essential for the ecosystem and human health. Reductive debromination of PBDEs by nanoscale zerovalent iron (nZVI) has become an important technology. However, the agglomeration and low persistence catalytic activity of nZVI particles have become urgent problems to be improved. Herein, we report the first application of a new organo-attapulgite (OA) supported Fe/Pd nanoparticles (OA-Fe/Pd) composite for decabromodiphenyl ether (BDE209) removal. BDE209 was efficiently removed using OA-Fe/Pd with a reaction rate that was 9.97 times greater than that of the nZVI due to the synergetic effect of support material OA and Pd loading. OA could prevent nZVI particles from agglomeration and adsorb BDE209 molecules to its surface. Pd could supply atomic hydrogen and also prevent the oxidation of nZVI particles. The degradation of BDE209 by OA-Fe/Pd was affected by many factors and followed pseudo first-order kinetics. The degradation of BDE209 by OA-Fe/Pd underwent a stepwise debromination manner with the H-transfer dominant mechanism. BDE209 (25 mg∙L -1 ) could be degraded to penta-BDEs to diphenyl ether (DE) by 3.0 g∙L -1 OA-Fe/Pd within 240 min under neutral condition. This study provides some inspiration for improving the removal efficiency of PBDEs with nZVI-based materials.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Kailun Luo,Zhihua Qiao,Weiyu Liang,Cong Lu,Mengru Fu,Shanqi Zhou,Yanna Han,Cheng Peng,Wei Zhang
Brominated flame retardants (BFRs) are widely used in various productions. As typical BFRs, polybrominated diphenyl ethers (PBDEs) are prohibited because of their toxicity and persistence. Some of the alternatives to PBDEs, new brominated flame retardants (NBFRs), have also been found in the environment and some have assigned hazardous properties and were categorized as persistent. In this study, a typical e-waste dismantling area was chosen as the study area, and the soil and rice samples were collected from the paddy fields around the circular economy park in Guiyu, China. The contaminations of PBDEs and NBFRs in soils and rice plants were detected, and the health risks associated with consumption and exposure to the environment were calculated as well. The concentrations of ∑PBDEs and ∑NBFRs in soil ranged from 283 to 928 μg/kg and 54.7–437 μg/kg, respectively. In rice plants, the majority of BFRs were concentrated in the following order: root > leaf > stem > grain. Additionally, only the PBT exhibited a stronger bioaccumulation ability in rice with the bioconcentration factors more than 1.00. The results of the health quotient calculation shown that BDE-47 might have an impact on people's health that only the HQ of BDE-47 in the soil was higher than 1.00, while there had no significant health risk in grain of BFRs. We believe that our work could assist researchers in investigating and revealing the human health effects of BFRs in soil and rice.
研究领域:
环境科学
·
毒理学
·
农业科学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2024
·
IF 8.1
Bin Li,Jianghong Shi,Xueling Xiang,Mengtao Zhang,Hui Ge,Shuhan Sun
Bromophenols has been proven to synthesize hydroxylated polybrominated diphenyl ethers (OH-PBDEs), which may pose additional environmental and health risks in the process of bioremediation. In this study, the removal of 2,4-dibromophenol (2,4-DBP) and 2,4,6-tribromophenol (2,4,6-TBP) and the biosynthetic of OH-PBDEs by Prorocentrum donghaiense were explored. The removal efficiencies of 2,4-DBP and 2,4,6-TBP ranged from 32.71% to 76.89% and 31.15%–78.12%, respectively. Low concentrations of 2,4-DBP stimulated algal growth , while high concentrations were inhibitory. Furthermore, exposure to 10.00 mg L −1 2,4-DBP resulted in the detection of 2′-hydroxy-2,3′,4,5′-tetrabromodiphenyl ether (2′–OH–BDE-68) within P . donghaiense . In contrast, increasing concentrations of 2,4,6-TBP considerably inhibited P . donghaiense growth, with 4′-hydroxy-2,3′,4,5′,6-pentabromodiphenyl ether (4′–OH–BDE-121) detected within P. donghaiense under 5.00 mg L −1 2,4,6-TBP. Metabolomic analysis further revealed that the synthesized OH-PBDEs exhibited higher toxicity than their precursors and identified the oxidative coupling as a key biosynthetic mechanism. These findings confirm the capacity of P. donghaiense to remove bromophenols and biosynthesize OH-PBDEs from bromophenols, offering valuable insights into formulating algal bioremediation to mitigate bromophenol contamination.
研究领域:
环境科学
·
海洋生物学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Kun-Hua Wang,Jun-Nan Yang,Qian-Kun Ni,Hong-Bin Yao,Shu-Hong Yu
Using nanocrystals as “artificial atoms” to construct supercrystals is an interesting process to explore the stacking style of nanoscale building blocks and corresponding collective properties. Various types of semiconducting supercrystals have been constructed via the assembly of nanocrystals driven by the entropic, electrostatic, or van der Waals interactions. We report a new type of metal halide perovskite supercrystals via the gold-bromide complex triggered assembly of newly emerged attractive CsPbBr3 nanocubes. Through introducing gold-bromide (Au–Br) complexes into CsPbBr3 nanocubes suspension, the self-assembly process of CsPbBr3 nanocubes to form supercrystals was investigated with the different amount of Au–Br complexes added to the suspensions, which indicates that the driven force of the formation of CsPbBr3 supercrystals included the van der Waals interactions among carbon chains and electrostatic interactions between Au–Br complexes and surfactants. Accordingly, the optical properties change with the assembly of CsPbBr3 nanocubes and the variation of mesoscale structures of supercrystals with heating treatment was revealed as well, demonstrating the ionic characteristics of CsPbBr3 nanocrystals. The fabricated CsPbBr3 supercrystal presents a novel type of semiconducting supercrystals that will open an avenue for the assembly of ionic nanocrystals.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 29
·期 3
·4461-4473
·
IF 4.223
Shao Jiang,Zhang Yi,Liu Zongtang,Fei Zhenghao,Sun Yufeng,Chen Ziyan,Wen Xiaoju,Shi Weizhong,Wang Dandan,Gu Chenggang
Organic palygorskite (OP)–supported Pd/Fe nanoparticles composite (OP-Pd/Fe) was prepared by stepwise reduction method. The removal capacity of 4,4′-dibrominated diphenyl ether (BDE15) by OP-Pd/Fe was compared with other various materials. For better understanding the possible mechanism, the synthesized and reacted OP-Pd/Fe materials were characterized by TEM, SEM, XRD, and XPS, respectively. The effects of major influencing parameters on the degradation of BDE15 were also studied. Benefit from the synergistic effect of the carrier and bimetallic nanoparticles, BDE15 could be completely debrominated into diphenyl ether (DE) under suitable conditions. A two-stage adsorption/debromination removal mechanism was proposed. The degradation of BDE15 with OP-Pd/Fe was mainly stepwise debromination reaction, and hydrogen transfer mode was assumed as the dominated debromination mechanism. The removal process fitted well to the pseudo first-order kinetic equation. The observed rate constants increased with increasing Pd loading and OP-Pd/Fe dosage while decreased with increasing initial BDE15 concentration, the tetrahydrofuran/water ratio, and the initial pH of the solution. The work provides a new approach for the treatment of PBDEs pollution.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Research Express
·
2017
·Vol. 4
·期 8
·085009
·
IF 1.068
Zongtang Liu,Chenggang Gu,Yongrong Bian,Xin Jiang,Yufeng Sun,Zhenghao Fei,Jingtao Dai
In this study, Fe/Ni bimetallic nanoparticles were supported on the attapulgite (A-Fe/Ni) to enhance the degradation reactivity of decabrominated diphenyl ether (BDE209) in aqueous solution. The Fe/Ni nanoparticles were well distributed on the attapulgite surface with an average diameter of 20–40 nm. The removal percentage of BDE209 by A-Fe/Ni was 1.59 times higher than Fe/Ni nanoparticles alone because attapulgite could act as supporting material to disperse Fe/Ni nanoparticles and prevent Fe/Ni nanoparticles from aggregation. The degradation kinetics for BDE209 debromination by A-Fe/Ni could be well described by a pseudo-first-order model, and the debromination rate constant of BDE209 increased with increasing the dosage of A-Fe/Ni, water/THF ratio, and decreasing the initial BDE209 concentration and solution pH. The degradation products were identified using a third-order polynomial regression equation between the experimental and reference gas chromatography relative retention times. Stepwise debromination from n-bromo-DE to (n − 1)-bromo-DE was a possible pathway with bromines being substituted sequentially by hydrogen. The preferred elimination of bromines of BDE209 by A-Fe/Ni followed the debromination preference of para-Br > meta-Br > ortho-Br. The results provide evidences for understanding the debromination mechanism of polybrominated diphenyl ether by clay-supported Fe/Ni nanoparticles.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
·
2018
·
IF 2.207
Qian Liu,Penghui Ren,Xiaofei Wang,Yuanzuo Li,Yanhui Yang
Tetrabromophenol blue and Bromoxylenol blue as the sensitizers of dye-sensitized solar cells (DSSCs) are measured in experiments. In order to better understand the photoelectrical properties of the two dyes, we obtain the UV-Vis spectra, fluorescence spectra, and current-voltage characteristics. The frontier molecular orbital, energy levels, the first hyperpolarizability, the first hyperpolarizability density, and molecular electrostatic potential are calculated with density functional theory (DFT) and time-dependent DFT (TDDFT). The critical factors including the light harvesting efficiency (LHE (Tetrabromophenol blue for 0.0284 and Bromoxylenol blue for 0.0290), the driving force of electron injection (ΔGinject), x-axis direction dipole moment (μnormal), the conduction band of edge of the semiconductor (ΔECB), and the excited-state lifetime (τ)) are computed, which have a close connection to the short-circuit current density (Jsc) and open-circuit voltage (Voc). The results show that the Jsc (0.09 mA/cm2) and Voc (0.39 V) of Tetrabromophenol blue have larger values, which can be explained by a larger absolute value of ΔGinject, absolute value of μnormal, τ, and ΔECB. Therefore, Tetrabromophenol blue displays well photoelectric conversion efficiency compared with Bromoxylenol blue.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2019
·Vol. 7
·期 35
·10783-10788
·
IF 6.641
Wenqiang Liu,Guodong Yuan,Yang Zhang,Qi Wang,Shuai Zhao,Zhiqiang Liu,Tongbo Wei,Junxi Wang,Jinmin Li
All-inorganic perovskite nanocrystals (NCs) have recently emerged as a new class of materials due to their tunable bandgaps and high photoluminescence quantum yields (PLQYs). The origin of the enhancement of PLQY of CsPbBr3 NCs is usually attributed to the efficient passivation of the surface halide vacancies creating nonradiative recombination sites. In this work, Br-rich CsPbBr3 NCs with a PLQY of 97% were prepared using an extreme excess of Br source with Br/Pb of 4.5/1 from the ligand itself at room temperature. Br-rich CsPbBr3 NC based light-emitting devices were fabricated under ambient conditions, exhibiting the maximum current efficiency of 1 cd A−1 at the luminance of 750 cd m−2. First principles calculations indicate that Br interstitials can form the strong localized states. Such localized effect can prevent photogenerated carriers from defusing to non-radiative recombination centers, thus being responsible for the high emission efficiency.
研究领域:
材料科学
·
纳米技术
·
光电
✓ 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）