CHEMICAL ENGINEERING JOURNAL
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2016
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IF 5.31
Yafei Guo,Changhai Li,Shouxiang Lu,Chuanwen Zhao
K 2 CO 3 supported on activated carbon (K 2 CO 3 /AC) shows promise as a potential candidate for removing low-concentration CO 2 from environmental control and life support systems (ECLSS). However, K 2 CO 3 /AC would suffer a decreased CO 2 sorption capacity due to sorbent deactivation in acid impurities such as SO 2 and NO 2 . To solve this problem, water vapor pretreatment, KOH addition and polyethyleneimine (PEI) modification were proposed as efficacious means for improving its CO 2 sorption capacity and mitigating the sorbent deactivation in these acid impurities. CO 2 sorption performances of the pretreated and modified sorbents were evaluated in a fixed-bed reactor under simulated ECLSS conditions of 20 °C, 1.0% CO 2 , 2.0% H 2 O, 30 ppm SO 2 , 20 ppm NO 2 and balanced N 2 . The mechanisms for sorbent deactivation inhibition by water vapor pretreatment, KOH addition and PEI modification were revealed by N 2 adsorption-desorption, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Effects of water vapor pretreatment duration, KOH addition and PEI loading on sorbent deactivation inhibition performances were demonstrated. Furthermore, the long-term working stabilities of the pretreated and modified sorbents in impurities were evaluated. The results will provide fundamental support on practical application of K 2 CO 3 /AC for low-concentration CO 2 removal in ECLSS.
研究领域:
环境控制与生命支持系统
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气体吸附
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材料化学
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空气净化技术
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二氧化碳捕集
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高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
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2017
·Vol. 43
·期 7
·3961-3974
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IF 1.369
Jiao Yinchun,Zhu Man,Deng Renjie,Jian Jian,Yin Yi,You Kuiyi
With the increase in environmental awareness, developing a highly efficient and environmentally benign nitration process has very important academic and applied industrial values in the synthesis of nitro-compounds. Towards this goal, we have developed an efficient and environmentally friendly approach for solvent-free liquid phase nitration of toluene by employing NO 2 as a nitrating agent and sulfated SO 4
2− /WO 3 as a catalyst replacing traditional nitric acid–sulfuric acid under mild conditions. The results indicate that SO 4
2− /WO 3 as an effective and eco-friendly catalyst exhibits excellent catalytic activity and reusability for the nitration of toluene with NO 2 . In addition, the possible pathway for liquid phase nitration of toluene with NO 2 over sulfated SO 4
2− /WO 3 catalyst was suggested. The present method makes this nitration process safe and environmentally friendly, and has the potential to enable a sustainable production of nitro-compounds from the liquid phase nitration of aromatic hydrocarbon with NO 2 in industrial applications.
研究领域:
催化化学
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绿色化学
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有机合成
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环境友好工艺
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工业化学
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高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2021
·
IF 3.995
Chao Chen,Haijian Li,Zhao Qin,Changjian Wang,Yi Xu,Zhihua Sun,Siyu Xu,Jianhua Yi,Fengqi Zhao
Hexanitro complex K 2 Ba[Ni(NO 2 ) 6 ] was prepared via the co-precipitation method, and its composition and morphology were characterized by XRD , SEM , XPS and FT-IR techniques. The catalytic performances of K 2 Ba[Ni(NO 2 ) 6 ] for CL-20, FOX-7 and TKX-50 thermolysis were also discussed and studied by using DSC and TG-DTG-MS. After K 2 Ba[Ni(NO 2 ) 6 ] were mixed with CL-20, the activation energy ( E a ) of thermolysis reaction was increased, while the heat release was greatly improved, and the transformation from NH 3 to NO occurred. It is attributed to that the decomposition products of K 2 Ba[Ni(NO 2 ) 6 ] have strong effects on the oxidation of the radicals and the electrons transfer . Besides, the thermolysis E a of FOX-7 by addition of the K 2 Ba[Ni(NO 2 ) 6 ] was increased by 81.03 kJ mol −1 , and the heat release was greatly increased. In addition to that the two-step separate thermolysis processes of pure FOX-7 was almost replaced by a one-step exothermic reaction for the FOX-7/K 2 Ba[Ni(NO 2 ) 6 ] mixture, which was due to that Ni 2+ cations could effectively increase the activity of amino groups in the FOX-7 thermolysis process. Finally, K 2 Ba[Ni(NO 2 ) 6 ] scarcely has the thermolysis catalytic activity of TKX-50 owing to the influence of metal cations on the decomposition of the hydroxylamine . Furtherly, the characteristics of ignition and flame propagation on the three energetic mixtures were strongly correlated to their thermolysis pathway and mechanism. The comparative study on the effects of K 2 Ba[Ni(NO 2 ) 6 ] to the CL-20, FOX-7 and TKX-50 thermolysis and ignition showed that the hexanitro complex has great significance on promoting the heat release efficiency of solid propellants for future study.
研究领域:
材料科学
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化学动力学
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含能材料
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催化化学
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热分析
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Jing Hu,Chenming Yin,Shouxi Xu,Miao Cheng,Tao Wei,Qianqian Liu,Wanfei Li,Yun Ling,Yafei Zhang,Bo Liu
Highly-sensitive gas sensors operating at room temperature (RT) have been pursued by researchers due to their high security, energy saving and long-term stability. Herein, N-doped carbon nanosheets-incorporated zinc oxide (NCZ) was synthesized via solution calcination combined with hydrothermal method and utilized for ppb level detection of NO 2 at RT. Intriguingly, the construction of N-doped carbon nanosheets was accompanied by generation of ZnO nanoparticles, and then be transferred into mesoporous nanoplates. The as-synthesized NCZ(120)-300 nanocomposites demonstrated high sensitivity to 3 ppm NO 2 (|R g- R 0 |/R 0 =∼28.2), along with fast response/recovery (60 s/129 s) speed, excellent selectivity and cyclic stability. In particular, the morphology transition of ZnO greatly enhanced the RT NO 2 sensing performance of the as-prepared sensor. Meanwhile, the white light illumination further ameliorated the sensor’s properties involving ∼ 2.1 times enhancement of sensitivity and shorter recovery process (accelerated from 563 s to 129 s). These enhancements are ascribed to the heterostructure between ZnO nanoplates and N-doped carbon nanosheets, and the modulation of electron structure by photo-generated electron-hole pairs. In addition, the 2D N-doped carbon nanosheets and mesoporous ZnO nanoplates offer numerous active adsorption-sites, which improved the surface chemical activity of NCZ(120)-300.
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Shanshan Shang,Chao Yang,Yuanmeng Tian,Zeyu Tao,Mallory Smith,Hongyan Zhang,Lin Zhang,Liangchun Li,Qinfen Gu,Hong-Cai Zhou,Yong Sik Ok,Jin Shang
Selective adsorption using porous materials is a promising approach to removing ambient nitrogen dioxide (NO 2 ). However, the highly reactive nature of NO 2 and the often-associated release of nitric oxide (NO) render a formidable challenge in developing effective and stable adsorbents. Here, we designed multivariate porphyrin-based metal–organic frameworks (MTV-PMOFs Al-PMOF(Ni x Co y )) featuring atomically dispersed Ni/Co dual-metal centers in the porphyrin ring as active adsorption sites, as robust adsorbents capable of synergistically boosting NO 2 adsorption capability and retaining the evolved NO. The introduction of the Ni/Co dual-metal sites in MTV-PMOFs greatly enhanced the NO x adsorption performance. Under dry conditions, Al-PMOF(Ni 1 Co 1 ) exhibited a NO 2 adsorption capacity of 3.66 mmol/g (100 ppm NO 2 in feed), among the highest under similar conditions, a high NO retention ability, and good regenrability (85%). Under wet conditions, its NO 2 removal capacity was further elevated by more than 50% (5.65 mmol/g). Moreover, the Ni/Co ratio in MTV-PMOFs dictates a structure–property relationship between the released amount of NO and adsorbed capacity of NO 2 . Such a corporative NO 2 and NO adsorption was for the first time established in MOFs. The material stability and potential economic value were also investigated to demonstrate the applicability of MTV-PMOFs as NO 2 adsorbents. This work provides new perspectives for the development of adsorption-based technology for mitigating ambient NO 2 pollution and managing other corrosive and toxic gases.
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高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2020
·
IF 6.146
Pengfei Zhu,Xiaohe Yin,Xinhua Gao,Guohui Dong,Jingkun Xu,Chuanyi Wang
The controlled introduction of oxygen vacancies (OVs) in photocatalysts has been demonstrated to be an efficient approach for improving the separation of photogenerated charge carriers, and thus, for enhancing the photocatalytic performance of photocatalysts. In this study, a two-step calcination method where ZIF-8 was used as the precursor was explored for the synthesis of ZIF-8-derived ZnO nanoparticles with gradient distribution of OVs. Electron paramagnetic resonance measurements indicated that the concentration of OVs in the samples depended on the temperature treatment process. Ultraviolet–visible spectra supported that the two-step calcined samples presented excellent light-harvesting ability in the ultraviolet-to-visible light range. Moreover, it was determined that the two-step calcined samples presented superior photocatalytic performance for the removal of NO , and inhibited the generation of NO 2 . These properties could be attributed to the contribution of the OVs present in the two-step calcined samples to their photocatalytic performance. The electrons confined by the OVs could be transferred to O 2 to generate superoxide radicals, which could oxidize NO to the final product, nitrate. In particular, the NO removal efficiency of Z 350-400 (which was a sample first calcined at 350 °C for 2 h, then at 400 °C for 1 h) was 1.5 and 4.6 times higher than that of Z 400 (which was one-step directly calcined at 400 °C) and commercial ZnO, respectively. These findings suggested that OV-containing metal oxides that derived from metal-organic framework materials hold great promise as highly efficient photocatalysts for the removal of NO.
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高影响因子
ACS Sensors
·
2021
·
IF 7.711
Qiuni Zhao,Deming Sun,Si Wang,Zaihua Duan,Zhen Yuan,Guangfen Wei,Jian-Long Xu,Huiling Tai,Yadong Jiang
Titanium carbide (Ti3C2Tx) with a distinctive structure, abundant surface chemical groups, and good electrical conductivity has shown great potential in fabricating superior gas sensors, but several challenges, such as low response kinetics, poor reversibility, and serious baseline drift, still remain. In this work, γ-poly(l-glutamic acid) (γ-PGA) with a blocking effect is exploited to modify Ti3C2Tx, thereby stimulating the positive response behavior of Ti3C2Tx and improving its gas sensing performance. On account of the unique synergetic interaction between Ti3C2Tx and γ-PGA, the response of the flexible Ti3C2Tx/γ-PGA gas sensor to 50 ppm NO2has been improved to a large extent (average 1127.3%), which is 85 times that of Ti3C2Tx (only 13.2%). Moreover, the as-fabricated Ti3C2Tx/γ-PGA sensor not only exhibits a shorter response/recovery time (average 43.4/3 s) compared with the Ti3C2Tx-based sensor (∼18.5/18.3 min) but also shows good reversibility and repeatability (relative standard deviation (RSD) <1%) at room temperature within 50% relative humidity (RH). The improved gas sensing properties of the Ti3C2Tx/γ-PGA sensor can be attributed to the enhancement of effective adsorption and the blocking effect assisted by water molecules. Furthermore, the gas sensing response of the Ti3C2Tx/γ-PGA sensor is studied at different RHs, and humidity compensation of the sensor is carried out using the multiple regression method. This work demonstrates a novel strategy to enhance the gas sensing properties of Ti3C2Tx by γ-PGA modification and provides a new way to realize highly responsive gas detection at room temperature.
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PubMed
高影响因子
IONICS
·
2019
·Vol. 25
·期 12
·6043-6050
·
IF 2.289
Diao Quan,Zhang Xiaomei,Li Jie,Yin Yuna,Jiao Mingli,Cao Jian,Su Chaohua,Yang Kai
The phenol-formaldehyde (PF) resin microspheres were firstly used as the template in the sensing electrode (SE) preparation process of sensors based on Y 2 O 3 stabilized ZrO 2 (YSZ). The PF resin microspheres were synthesized by a facile hydrothermal method. The high char yield and the few morphological changes of PF resin microspheres before and after sintering at 900 °C indicated the perfect thermal stability at high temperature. The sensors using MnCr 2 O 4 admixed with various contents PF microspheres (0 wt%, 5 wt%, 10 wt%, and 20 wt%) were fabricated and their sensing performances on NO 2 gas were also investigated. The sensor with sensing electrode prepared by MnCr 2 O 4 with 10 wt% PF showed the best NO 2 sensing performance with a response of 110.8 mV to 100 ppm NO 2 as well as the higher sensitivity (87.4 mV/decade) with the NO 2 concentration ranging from 10 to 500 ppm at 550 °C. According to the mixed-potential mechanism, the porous electrode is good for gas penetration, so the gas can easily reach the MnCr 2 O 4 /YSZ/gas triple phase boundary (TPB) to participate in the electrochemical reactions. Additionally, the sensor exhibited excellent selectivity and repeatability, which indicated its potential application in the NO 2 detection.
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Jian-Bo Chen,Baosheng Li,Ying Xiong,Jie Sun
Two new fluorescent probes based on a coumarin core have been developed for the detection of nitramines (RDX and HMX) via responding to their photo-degradated nitrogen dioxide (NO 2 ). Although both probes contain the same fluorophore and recognition site, they display different fluorescent responses to NO 2 and nitramines. 8- O xime-7-dimethylamino-coumarin (8-ODC) emits traditional turn-on fluorescence toward NO 2 , which is based on the C N isomerization. In contrast, 3- O xime-7-dimethylamino-coumarin (3-ODC) exhibits a unique turn-off response with strong fluorescence quenching (about 98%) as a result of a twisted intramolecular charge transfer mechanism (TICT). In addition, 3-ODC offers a highly selective and sensitive determination of nitramines via detecting NO 2 in solution. The limit of detection of 3-ODC for NO 2 , HMX and RDX was 90 ppb, 60 nM and 90 nM, respectively. Notably, main interferents such as TNT, PETN, NO, NO 2 + and H 2 O 2 showed no obvious interference to the detection of NO 2 and nitramines. Therefore, a novel fluorescent probe (3-ODC) based on the TICT mechanism was firstly developed to detect NO 2 and nitramines by fluorescence quenching with high selectivity and sensitivity.
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Ziying Wang,Chen Zhao,Tianyi Han,Yong Zhang,Sen Liu,Teng Fei,Geyu Lu,Tong Zhang
Reduced graphene oxide (RGO)-based NO 2 sensors have attracted considerable attention due to their excellent advantages of low power consumption and manufacturability to facilitate massive deployment. However, it is still a great challenge to fabricate RGO-based room-temperatureNO 2 sensors with excellent sensing performances. Herein, we have demonstrated a combined surface modification and heteroatom doping approach to enhance the sensing performances of RGO-based room-temperature NO 2 sensors, where SnO 2 nanoparticles modified nitrogen-doped RGO (SnO 2 /N-RGO) hybrids had been used as sensing materials. The SnO 2 /N-RGO hybrids were prepared by hydrothermal synthesis method using SnCl 4 , GO and urea as precursors. The combined characterizations of X-ray diffraction (XRD), energy-dispersive X-ray spectrometer (EDS), elemental mapping, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), Raman spectra as well as N 2 sorption isotherm were used to characterize the materials thus obtained, indicating the successful preparation of SnO 2 /N-RGO hybrids. During the hydrothermal progress, SnCl 4 conversed into SnO 2 nanoparticles (NPs), and GO was reduced into RGO, while urea was decomposed into nitrogen-containing molecule and doped into RGO. It is found that SnO 2 NPs with the size of 3–5 nm are uniformly dispersed on N-RGO nanosheets. Most importantly, SnO 2 /N-RGO hybrids-based sensor exhibits superior sensing performances toward NO 2 operated at room temperature, which are better than those of pure RGO and SnO 2 /RGO hybrids. For example, SnO 2 /N-RGO hybrids show response of 1.38 to 5 ppm NO 2 with the response time and recovery time of 45 s and 168 s. The excellent sensing performances are attributed to incorporation of N atoms into RGO and the modification of RGO with SnO 2 NPs. This novel sensor based on SnO 2 /N-RGO hybrids promises to provide an essential sensing platform for the detection of NO 2 with excellent sensing performances at room temperature.
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2024
·
IF 8
Xingyu Kang,Jianhui Lv,Lei Han,Bin Huang,Huizhang Zhao,Dong Wang,Hairui Fang
Nitrogen oxide (NO 2 ) is common by-products of industrial production, posing significant health risks to workers. Therefore, real-time monitoring of NO 2 is crucial. In this study, innovative In 2 O 3 -ZnO nano-materials were prepared by combining In 2 O 3 with ZIF-8 via electrospinning, for detecting trace amounts of NO 2 at room temperature (RT). Compared to pure In 2 O 3 , the In 2 O 3 -ZnO nano-materials (V2) with a 10 % weight ratio of ZIF-8 exhibited a significantly higher response (389.99) and a faster response time (16.9 s) to NO 2 under ultraviolet (UV) irradiation at RT. The superior gas sensing performance of the V2 nano-materials is attributed to the formation of n-n heterojunctions, enhanced optical absorption, increased oxygen vacancy ratio, and excellent dispersion among the nano-materials. The results demonstrate that V2 nano-materials can detect NO 2 at parts-per-billion (ppb) levels at RT, making them suitable for monitoring trace amounts of NO 2 in open environments. Furthermore, a portable real-time NO 2 monitoring device was constructed using V2 as the sensing material, an LM358-based amplifier circuit for data acquisition, an STM32F103C8T6 microcontroller as the main control unit, and a buzzer as an alarm device. Compared to devices using a helical Ni-Cr wire as an indirect heat source, this integrated NO 2 detection device offers real-time alarms with lower energy consumption. This application not only enhances worker health and safety in industrial environments but also demonstrates higher energy efficiency in practical application.
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高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Evans Kibet,Yingchun Dong,Yuanting Yu,Wen Niu,Yiling Tan,Hangyu Liu,Jiongyue Hao,Weijie Qu,Yong Zhou,Wei Hu,Simon Mugo,Bingsheng Du,Anthony Kiroe,Yong He
The development of high-performance and low-operating-temperature gas sensors is critical for real-time environmental and industrial process monitoring applications. In this study, we report the synthesis and application of a bismuth-based metal–organic framework (Bi-MOF)-derived Bi2Se3 sensor for the detection of NO2 at room temperature. Bi2Se3 was synthesized through a controlled selenization process that resulted in synergistic effects between Bi-MOF and Bi2Se3. The changes in morphology and surface physicochemical properties caused by the selenization process led to the tunability of the NO2 gas sensing properties. The Bi-MOF-derived Bi2Se3 sensitive materials were characterized using XRD, SEM, transmission electron microscopy, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and BET to analyze their morphology, composition, pore structures, intensity of Se vacancies, and surface properties. The gas sensing performances were assessed under various NO2 concentrations, evaluating the sensitivity, selectivity, and resistance to humidity. Our findings show that the Bi2Se3 sensor exhibits excellent sensitivity and selectivity toward NO2 at room temperature. The best sensor showed a response of 32.1% toward 0.5 ppm of NO2 with a response/recovery time of 60.1/365.4 s, making it a promising candidate for NO2 monitoring. This study provides significant insights into the potential of Bi-MOF-derived Bi2Se3 materials in gas sensing, laying the groundwork for further research to optimize these sensors for practical applications.
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