SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Yiqun Chen,Baitian Zeng,Liying Long,Qing Shao,Zizheng Liu,Feng Wu,Pengchao Xie
The ultraviolet/persulfate (UV/PS) process has attracted more and more attention for water treatment. However, it runs the risk of producing bromate in the presence of bromide ions. In this work, we propose a new strategy using sulfite to inhibit bromate formation. The results show that the addition of sulfite significantly reduced the formed bromate in the UV/PS system by 61.2% and 24.5% in 30 min and 120 min, respectively. Increasing sulfite dosage or pH could enhance bromate control. From the standpoint of reaction kinetics, sulfite is likely to inhibit bromate formation by reducing bromine radicals (Br ) back to bromide ions, the energy profile of which was quantified by density functional theory (DFT) calculations. In the UV/PS/sulfite system, the conversion of SO 3 − to HO was observed, indicating that sulfite also served as a source of reactive radicals. Moreover, sulfite apparently promoted the degradation of benzoic acid and phenol in a UV/PS system, showing advantages over other inorganic reductants. As a result, we discovered that sulfite could not only help control bromate formation in UV/PS but also improve the system’s oxidation capacity.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Min Chen,Jiangzhou Luo,Jun Hu,Yuxuan Zhao,Honglei Ling,Xueping Zong,Song Xue
The network polyimide (PI) precursor is a promising candidate to fabricate the advanced carbon molecular sieve (CMS) membrane since its robust crosslinked structure could prevent pore structure collapse during CMS formation. Exploring the relationship between network PI precursor structure and CMS membrane is highly significant. Herein, a novel brominated network PI precursor was fabricated via in-situ cross-linking technique firstly, and then the thermally induced bromination/debromination process was applied to tune the microporosity and gas transport properties of network PI precursor and its derived CMS membranes. After the bromination/debromination and carbonization at 550 °C, the resultant CMS membrane exhibited both high gas permeability and gas selectivities compared to its un-brominated network PI precursor derived CMS membrane. This is due to the bromination/debromination and carbonization enable the CMS membrane possesses large d -spacing values (11.06 Å), high BET surface areas (538.57 m 2 /g), and high percentage (∼71 %) of ultra-micropores. For instance, 6F-TA/TA-Br-550/30 membrane exhibits great CO 2 /CH 4 separation ability, with a CO 2 permeability of 6300 Barrer and a CO 2 /CH 4 selectivity of 46.11, which is suppressed the latest 2019 trade-off curves. We anticipate that the present bromination/debromination and carbonization could provide a fresh perspective on the rational design of network PI precursor and its derived CMS membrane with excellent gas separation performance.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Qiming Zhang,Hang Jiang,Siting Liu,Qianyun Wang,Jianwei Wang,Zhikang Zhou,Kedi Cai,Qinzhi Lai,Qian Wang
Zinc-bromine flow batteries (ZBFBs) are considered as one of the most promising energy storage technologies, owing to the high energy density and low cost. However, the sluggish electrochemical kinetics and severe self-discharge lead to the limited power density and service life, hindering the practical application of ZBFBs. Herein, Prussian blue modified nitrogen-doped carbon (PB@NC) is synthesized as an auxiliary redox-targeting catalyst for the bromine cathode. The excellent conductivity and adsorption capability of nitrogen-doped carbon (NC) ensure the smooth electron transfer and the enriched bromine species at the reaction interface. Under the assistance of NC, Prussian blue (PB) could rapidly lose or gain electrons, then transform into the oxidized or reduced states that subsequently engages in the targeted redox reactions with the contacted Br ‐ or Br 2 . It offers an alternative reaction pathway for the bromine redox, promoting the electrochemical kinetics significantly, which demonstrates a reversible redox-targeting catalytic effect. Therefore, a ZBFB modified with PB@NC achieves an energy efficiency of 85.9% at a current density of 80 mA cm −2 , and ultra-high energy efficiency of 71.1% even at current density of 160 mA cm −2 . This work offers a promising strategy for advancing the development of ZBFBs by the efficient cathode material design.
研究领域:
材料科学
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电化学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENT INTERNATIONAL
·
2019
·
IF 7.943
Xiao-Qiu Lin,Zhi-Ling Li,Ying-Ying Zhu,Fan Chen,Bin Liang,Jun Nan,Ai-Jie Wang
Tetrabromobisphenol A (TBBPA) has aroused serious pollution in surface sediment. To date, whether and how iron-based nanoparticles could stimulate TBBPA in situ anaerobic biodegradation in sediment remains poorly understood. In this study, the distinctly enhanced TBBPA degradation activity with the rate constant k improved 4.7 times by fed with Pd/Fe nanoparticles (0.412 g L −1 dosage, 0.5 wt% Pd loading) was observed. TBBPA degradation first went through reductive dehalogenation with bisphenol A (BPA) as the metabolites, and after the addition of Pd/Fe nanoparticles, BPA was further degraded to 4-(allene)phenol and 2,2-bis(4-hydroxyphenyl) propanoic acid via UPLC-QTOF-MS analysis, suggesting the complete detoxification potential. By the addition of Pd/Fe nanoparticles, the large amount of H 2 production (560 times higher) and the significant inhibition of methane generation facilitated the metabolism of potential reductive dehalogenators ( Desulfovibrio , Clostridium , etc.), demonstrated by their increased ecological abundance and the tighter cooperative interrelations between each other. Meanwhile, the addition of Pd/Fe nanoparticles largely promoted the ecological abundance of Fe(III) reducing and aromatics degrading bacteria ( Bacillus , Cryptanaerobacter , etc.), resulting in BPA further degradation. The bacterial ecological network further revealed that the potential BPA degrading bacteria shared the more positive interactions with the potential dehalogenators in the presence of Pd/Fe nanoparticles. The study firstly revealed the addition of Pd/Fe nanoparticles obviously enhanced the respiratory metabolic activities and cooperative interrelations of reductive dehalogenators and BPA degraders, which gives suggestions for in situ remediation and detoxification of BFRs in contaminated sediment.
研究领域:
环境科学
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 9
·期 6
·2016-2023
·
IF 7.059
Fengyou Qin,Hongjun Tian,Minxing Yan,Yanjun Fang,Deren Yang
Perovskite light-emitting diodes (PeLEDs) have drawn tremendous research attention recently. However, they are mainly prepared via solution processes, while the devices fabricated using the all-vacuum deposition procedure still remain largely unexplored. In this work, we prepared a cesium-lead-bromide perovskite film using the vacuum deposition method, and realized a more balanced stoichiometry by replacing some CsBr with NaBr. It was discovered that the introduction of an appropriate amount of NaBr not only reduced the insulating Cs4PbBr6 phase in the active layer, but also passivated the trap states effectively, which resulted in a 2-fold increase of the peak external quantum efficiency (EQE) of the PeLEDs to 2% with the maximum luminance reaching close to 40 000 cd m−2 and significantly improved device operational stability compared to the undoped counterparts. Furthermore, we fabricated the first top-emissive silicon-based PeLED using the all-vacuum deposition method based on the NaBr doped perovskite films, and achieved a peak EQE of 0.33%, which has provided a promising alternative way for the design and preparation of high-performance silicon-based display devices in the future.
研究领域:
材料科学
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光电技术
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2019
·
IF 7.913
Chao Fang,Shunke Ding,Shibo Gai,Rong Xiao,Yinan Wu,Bing Geng,Wenhai Chu
The present study investigated the effect of oxoanions on catalytic behaviour of copper corrosion products (CCPs) during chlorination of bromide-containing waters. Three types of oxoanions (carbonate, sulphate, and phosphate) and four types of CCPs (Cu 2+ , Cu(OH) 2 , Cu 2 O, and CuO) were involved in investigation and the effect of oxoanions concentration was also examined. The result indicated that carbonate and sulphate slightly inhibited oxidant decay in the presence of CCPs, but the formation of brominated disinfection by-products (Br-DBPs) remained largely unchanged. In contrast, the presence of phosphate (0.2–1 mM) almost eliminated the catalytic effect of Cu 2+ . For CCP solids (i.e. Cu(OH) 2 , Cu 2 O, and CuO), phosphate preferentially inhibited the formation of bromate rather than Br-DBPs. Despite the catalysis by CCP solids was reduced to some extent, the oxidant decay rate and bromate and Br-DBP formation were still significantly higher than blank groups, even at high phosphate concentration. By testing different addition scheme (simultaneous/sequential addition), it was proposed that phosphate was a strong competitor for hypohalites, rapidly destroying CCPs-hypohalites complexes on some adsorption sites. However, there were some specific sites that can only be adsorbed by hypohalites, leading to the incomplete inhibition of phosphate. Finally, the inhibition effect of phosphate on CCPs catalysis was tested in real water matrix. For Cu 2+ , higher reduction of bromate and Br-DBPs was found in raw water rather than filtered water, while converse pattern was true for Cu(OH) 2 and Cu 2 O, and this discrepancy can be ascribed to the difference in catalytic mechanism between Cu 2+ and CCP solids.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Rui Wang,Zhixin Zhu,Shufei Tan,Jie Guo,Zhenming Xu
Degradation of brominated flame retardants (BFRs) in waste printed circuit boards (WPCBs) occurred due to mechanical force during the crushing process. In this study, a planetary ball-milling simulation experiment was designed to explore the mechanochemical debromination process of BFRs in WPCBs. The results showed that CaO had a better debromination performance than MgO and the mixture of Fe + SiO 2 , and high revolution speed and low mass ratio of WPCBs to CaO promoted the degradation of BFRs. After milling for 1 h, the particle size distribution was stable while the debromination efficiency increased with the increase of milling time. Ball milling promoted the migration of bromine from the inside to the new surface of WPCBs powder, and submicron particles adhered to the micron size aggregates. The polybrominated diphenyl ethers (PBDEs) detection showed that the concentrations of most PBDE congeners decreased with the increase of milling time, and a possible degradation pathway was proposed according to the experimental results. All the results provided new data for the mechanism of degradation of BFRs in WPCBs during the mechanical crushing process.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Pei Dai,Dajiao Hou,Shun Guo,Lihua Zhu,Ming Lei,Heqing Tang
A new determination method for total bromine in electronic devices was developed by using ultrasound assisted extraction , copper-catalyzed reductive debromination and ion chromatography (UAE-RD-IC). It was found that all the added brominated flame retardants (polybrominateddiphenyl ethers, polybrominated biphenyls , tetrabromobisphenol A, and hexabromocyclododecane) could be completely debrominated by using copper-based catalysts and reducing agent N 2 H 4 •H 2 O. The complete debromination of brominated flame retardants released all of their bromine in the form of bromide ions, which could be determined by ion chromatography. After the extraction parameters were optimized by achieving the maximum IC signal in the certified reference material GBW(E) 082725, the UAE-RD-IC method was established for the determination of total bromine in solid samples. By analyzing the certified reference material, the Br content was obtained as 695.3 ± 16.0 mg kg −1 , being well consistent with its standard value (694.54 ± 30.63 mg kg −1 ). The relative standard deviation (RSD) of five parallel determinations was 1.7%, indicating the good repeatability of the developed method. The proposed method was further applied to analyze the samples of cables and computer mouse shells. For all these practical samples, the Br contents obtained by the UAE-RD-IC method were in good agreement with that obtained by the standard oxygen bomb combustion-IC method. It was noted that the new method has a detection limit of Br of about 20 mg kg −1 , being much lower than that (75 mg kg −1 ) of the traditional oxygen bomb combustion-IC method for total bromine detection. Therefore, the proposed method was qualified as a practical method to measure total bromine content in actual electronic devices with good analytical performances of accuracy, precision and sensitivity.
研究领域:
分析化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Yao Li,Min Zhang,Rongjie Hao,Huihui Wang,Xizhen He,Tingting Du,Xin Yang,Yingying Wang
The rapidly increasing use of graphene oxide (GO) necessitates the immediate investigation of the environmental fate and effects of this unique material. To date, little is known about the transformation of GO in environmental media, especially in water and wastewater treatment systems. This study explored the changes in the physicochemical properties of GO that result from (photo)bromination by simulating the reactions experienced by GO during water and wastewater treatment. The surface oxygen functionalities of GO considerably changed upon treatment. Specifically, the C OH and COOH groups of GO were lost under bromination , and the reduction of GO was enhanced under photobromination. GO sheets wrinkled and fragmented under bromination, and GO decomposition was enhanced by photobromination. The decreases in O/C ratio and GO decomposition in the presence of bromine were mainly attributed to the relatively high oxidation potential of bromine, which can oxidize carbon nanosheets. The oxidation of carbon nanosheets, in turn, resulted in the decomposition and formation of brominated disinfection by-products. Irradiation, hypobromous acid/hypobromite (HOBr/OBr − ), and reactive radicals, such as OH, Br , BrO and Br 2 − , may all affect the physicochemical transformation of GO in the presence of bromine and simulated solar light. Bromination and photobromination drastically changed the aggregation and sedimentation behavior of GO. The findings of this study advance knowledge on the transformations of GO in water treatment systems and provide insight on the environmental fate of the transformation products of GO.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2021
·Vol. 17
·期 43
·2101359
·
IF 13.281
Hao Lin,Qi Wei,Kar Wei Ng,Jia-Yi Dong,Jie-Lei Li,Wei-Wei Liu,Shan-Shan Yan,Shi Chen,Gui-Chuan Xing,Xiao-Sheng Tang,Zi-Kang Tang,Shuang-Peng Wang
Colloidal all-inorganic perovskites nanocrystals (NCs) have emerged as a promising material for display and lighting due to their excellent optical properties. However, blue emissive NCs usually suffer from low photoluminescence quantum yields (PLQYs) and poor stability, rendering them the bottleneck for full-color all-perovskite optoelectronic applications. Herein, a facile approach is reported to enhance the emission efficiency and stability of blue emissive perovskite nano-structures via surface passivation with potassium bromide. By adding potassium oleate and excess PbBr 2 to the perovskite precursor solutions, potassium bromide-passivated (KBr-passivated) blue-emitting (≈450 nm) CsPbBr 3 nanoplatelets (NPLs) is successfully synthesized with a respectably high PLQY of 87%. In sharp contrast to most reported perovskite NPLs, no shifting in emission wavelength is observed in these passivated NPLs even after prolonged exposures to intense irradiations and elevated temperature, clearly revealing their excellent photo- and thermal-stabilities. The enhancements are attributed to the formation of K-Br bonding on the surface which suppresses ion migration and formation of Br-vacancies, thus improving both the PL emission and stability of CsPbBr 3 NPLs. Furthermore, all-perovskite white light-emitting diodes (WLEDs) are successfully constructed, suggesting that the proposed KBr-passivated strategy can promote the development of the perovskite family 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
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Xueqing Jin,Yeting Zhang,Jialing Huang,Longyi Xu,Qi Shen,Chunyan Sun
Activation of carbon-halogen bonds is vital for realizing the degradation of halogenated pollutants. Herein, zinc indium sulfides Zn x In 2 S x+3 (x = 1, 2 and 3) with different sulfur vacancies concentration were constructed to achieve photocatalytic decabromodiphenyl ether (BDE209) debromination. Under irradiation, ZnIn 2 S 4 had the most outstanding degradation ability to BDE209, attributing to its abundant surface sulfur vacancies. The sulfur vacancies not only can narrow the forbidden band to increase light absorption and utilization, but more importantly, serve as active sites for the adsorption and activation of C-Br of BDE209. Interestingly, the removal of the first bromine atom from BDE209 on sulfur vacancies behaved as a meta- selective debromination process. The selectivity of meta- debromination is as high as 70%, superior to that on oxygen vacancies enriched photocatalyst. It can be ascribed to the larger vacancy space of sulfur to better accommodate bromine atoms in BDE209, which helps to stabilize the meta- bromine adsorption configuration of BDE209 on sulfur vacancies. Meanwhile, the intermediate configuration is further stabilized under the assistance of the S…Br halogen bond by surrounding sulfur atom at the catalytic interface. This work sheds light on the great potential of larger element vacancies to activate C-halogen bonds in photocatalytic treatment of halogenated pollutants.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Zhenyu Chen,Lu Zhan,Zhenming Xu
Bromine removal is significant in the recycling of waste printed circuit boards (WPCBs). This study found that the critical factors limiting the debromination efficiency of conventional pyrolysis are the formation of coke impeding mass transfer and conversion of bromine into less volatile species, such as coking-Br and copper bromide. According to frontier molecular orbital analysis and thermodynamic equilibrium analysis, C–O bonds of resin are sites prone to electrophilic reactions and copper bromide in residue may undergo hydrolysis; therefore, introducing H2O during pyrolysis was a feasible method for thorough debromination. Through pyrolysis in a water vapor atmosphere, the diffusion limitation of debromination was overcome, and resin was converted into light components; thereby, rapid and deep removal of bromine was achieved. The result indicated that 99.7% of bromine was removed, and the residue could be used as a clean secondary resource. According to life-cycle assessment, pyrolysis of WPCBs in water vapor could be expected to reduce 77 Kt of CO2 emission and increase financial benefits by 60 million dollars, annually.
研究领域:
环境科学
·
化学工程
·
材料科学
·
可持续性
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）