INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Qiuyu Zeng,Yifan Wang,Ansar Javeed,Fengyun Chen,Jiaxing Li,Yating Guan,Baiyu Chen,Bingnan Han
To address the issue of food spoilage causing health and economic loss, we developed a pH/NH 3 dual sensitive hydrogel based on polyvinyl alcohol/chitosan (PVA/CS) containing chitosan-phenol red (CP). The CP was synthesized via Mannich reaction and immobilized it in PVA/CS hydrogel through freezing/thawing method to prepare the final PVA/CS/CP hydrogel. The synthesis of CP was confirmed by 1 H NMR, FT–IR, XRD, UV–vis, and XPS. The characteristics of hydrogel were evaluated by FT–IR, XRD, SEM, mechanical properties, thermal stability, leaching, and color stability tests. The PVA/CS/CP hydrogel showed distinctly different color at various pH and NH 3 vapor levels (yellow to purple). The hydrogel exhibited obvious color changes (ΔE = 46.95) in response to shrimp spoilage, stored at 4 °C. It showed positive and strong correlation between the ΔE values of the indicator hydrogel and total volatile basic nitrogen (TVB-N) as (R 2 = 0.9573) and with pH as (R 2 = 0.8686), respectively. These results clearly show that the PVA/CS/CP hydrogel could be applied for naked-eye real-time monitoring of seafood freshness in intelligent packaging.
研究领域:
食品科学
·
材料科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Shuohan Yu,Yiyang Lu,Yuan Cao,Jiaming Wang,Bowen Sun,Fei Gao,Changjin Tang,Lin Dong
Mn-based catalysts were believed to be promoting low temperature NH 3 -SCR catalysts for their satisfactory catalytic activity, whereas their poor SO 2 and H 2 O tolerance inhibited their applications. In this work, utilizing poor SO 2 tolerance of Mn oxides, composite catalytic systems containing Mn oxides as deSO x catalyst was designed and synthesized, which exhibited excellent low temperature NH 3 -SCR performance in the presence of SO 2 and H 2 O. The deSO x mechanism of Mn oxides was systematically investigated. In results, SO 2 was catalytic oxidized on the surface of Mn oxides. Oxidized sulfur species could flow away from Mn oxides surface through feed gas flow or form MnSO 4 . When NH 3 and H 2 O were introduced into the feed gas, the oxidized sulfur species were completely deposited as NH 4 HSO 4 instead of forming MnSO 4 . Thus, SO 2 was removed from feed gas entirely resulting in the superb low temperature NH 3 -SCR performances. This work provided a general strategy to enhance SO 2 and H 2 O tolerance of NH 3 -SCR catalysts at low temperature by removing SO 2 using NH 3 and H 2 O who existed in the exhaust gas from stationary sources.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2025
·
IF 3.7
Dingding Liu,Yating Huang,Zhenguo Li,Guohua Jing,Yongdan Li,Huawang Zhao
The advancements in engine technology have led to a decrease in exhaust temperatures, hence enhancing the activity of Cu-SSZ-13 at low temperatures becomes crucial and challenging. This enhancement can be achieved using dual-phase metal oxide/Cu-SSZ-13 composite catalysts. In this work, we evaluated the comparative efficacy of Mn 3 O 4 and Mn 2 O 3 and discovered that Mn 3 O 4 exhibited a significantly superior enhancement in deNO x activity of Cu-SSZ-13 at low temperatures, achieving 95% NO x conversion at 200 °C. This is substantially higher than the conversions recorded by Mn 2 O 3 /Cu-SSZ-13 (78%) and Cu-SSZ-13 (40%). Kinetic and IR results demonstrate that Mn 3 O 4 /Cu-SSZ-13 and Mn 2 O 3 /Cu-SSZ-13 composite samples share a same low-temperature pathway, where bridged nitrates formed on the MnO x react with adsorbed on Brønsted acid sites in Cu-SSZ-13. In this reaction pathway, bridged nitrate formation is identified as the rate-determining step. The distinctive structure of Mn 3 O 4 triggers an increase in oxygen vacancies, creating a higher content of chemically adsorbed oxygen, compared to Mn 2 O 3 . Those adsorbed oxygen facilitates bridged nitrate formation. Consequently, due to the larger amount of bridged nitrate formed on Mn 3 O 4 compared to Mn 2 O 3 , the Mn 3 O 4 /Cu-SSZ-13 sample exhibits higher activity.
研究领域:
环境催化
·
材料化学
·
大气污染控制
·
化学工程
·
表面科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2021
·
IF 7.92
Jiawei Ji,Meizan Jing,Xiuwen Wang,Wei Tan,Kai Guo,Lulu Li,Xin Wang,Wang Song,Lijun Cheng,Jingfang Sun,Weiyu Song,Changjin Tang,Jian Liu,Lin Dong
The occurrence of NH 3 -SCR (selective catalytic reduction of NO with NH 3 ) reaction on catalyst surface typically requires acid and redox sites. However, the role of acid-redox interaction on NH 3 -SCR performance is still obscure due to complex acidities and entangled acid-redox sites. Herein, three types of model Ce 2 (SO 4 ) 3 -CeO 2 catalysts with distinct interfaces are constructed to reveal the effect of acid-redox interaction on NH 3 -SCR performance. That is, SO 4 2- /CeO 2 -VS (vapor sulfation of ceria) with strong acid-redox interfacial contact, SO 4 2- /CeO 2 -WI (wet impregnation), and SO 4 2- /CeO 2 -SG (solid grinding) with limited interfaces. It is found the redox property is significantly disturbed as a result of the electron-withdrawing effect from the sulfate. Theoretical result unravels that the introduction of Ce 2 (SO 4 ) 3 retards the oxygen vacancy formation over CeO 2 . Due to restricted interfaces in SO 4 2- /CeO 2 -SG, the negative influence from acid sites is greatly alleviated. Further mechanism study discloses the weakened acid-redox interaction actually changes the nature of surface NO x species, resulting in the generation of reactive species (*O-N-O* and cis -N 2 O 2 2- ) and the promotion of surface reaction via Langmuir-Hinshelwood (L-H) mechanism.
研究领域:
催化化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Lei Chen,Zhichun Si,Xiaodong Wu,Duan Weng
A CuO–CeO2–TiO2 catalyst for selective catalytic reduction of NOx with NH3 (NH3-SCR) at low temperatures was prepared by a sol–gel method and characterized by X-ray diffraction, Brunner–Emmett–Teller surface area, ultraviolet–visible spectroscopy, H2 temperature-programmed reduction, scanning electron microscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). The CuO–CeO2–TiO2 ternary oxide catalyst shows excellent NH3-SCR activity in a low-temperature range of 150–250 °C. Lewis acid sites generated from Cu2+ are the main active sites for ammonia activation at low temperature, which is crucial for low temperature NH3-SCR activity. The introduction of ceria results in increased reducibility of CuO species and strong interactions between CuO particles with the matrix. The interactions between copper, cerium and titanium oxides lead to high dispersion of metal oxides with increased active oxygen and enhanced catalyst acidity. Homogeneously mixed metal oxides facilitate the “fast SCR” reaction among Cu2+–NO, nitrate (coordinated on cerium sites) and ammonia (on titanium sites) on the CuO–CeO2–TiO2 catalyst at low temperatures.
研究领域:
环境催化
·
材料化学
·
表面科学
·
化学工程
·
大气污染控制
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2018
·
IF 5.651
Junli Wang,Shaojuan Zeng,Feng Huo,Dawei Shang,Hongyan He,Lu Bai,Xiangping Zhang,Jianwei Li
A large number of NH 3 emissions from industries, such as ammonia plant purge gas , tail gases of urea plants and ammonium molybdate plants, inevitably cause serious air pollution problems, such as fog and haze, which has raised extensive attentions worldwide. However, the commercial methods, like water scrubbing and acid scrubbing, substantially transfer the NH 3 pollute from gas phase to liquid or solid phase, which does not mean total elimination. How to realize efficiently separate and recover NH 3 form NH 3 -containing gas mixtures is still a great challenge. In order to develop efficient absorbents for NH 3 removal, a series of metal (copper (Cu), stannum (Sn), nickel (Ni), manganese (Mn), cadmium (Cd), zinc (Zn), ferrum (Fe)) ionic liquids (MILs) were synthesized, and their physicochemical properties and NH 3 absorption performance were systematically investigated. The results implied that the incorporation of metal center into ILs has a great effect on NH 3 absorption. Among the investigated MILs, bis(1-butyl-3-methyl imidazolium) copper tetrachloride salt ([Bmim] 2 [CuCl 4 ]) and bis(1-butyl-3-methyl imidazolium) stannum tetrachloride salt ([Bmim] 2 [SnCl 4 ]) show excellent NH 3 absorption capacities up to 0.172 gNH 3 ·gIL −1 and 0.106 gNH 3 ·gIL −1 , respectively, which are far more than most of the conventional ILs. Moreover, the high selectivity for NH 3 /N 2 , NH 3 /CO 2 and NH 3 /O 2 of [Bmim] 2 [CuCl 4 ] and [Bmim] 2 [SnCl 4 ] indicated that these MILs can selectively separate NH 3 from NH 3 -containing gases. The absorption mechanism was further studied using Fourier transform infrared (FT-IR) spectroscopy and quantitative chemical calculations. It was demonstrated that the chemical complexation between [Bmim] 2 [CuCl 4 ] and NH 3 plays a dominant role in NH 3 absorption, but the stronger hydrogen bonding between [Bmim] 2 [SnCl 4 ] and NH 3 enhances the absorption performance. In addition, [Bmim] 2 [SnCl 4 ] can keep good stability after five absorption and desorption cycles, implying this MIL shows great potentials as an efficient and reversible absorbent for NH 3 capture applications.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 27
·14326-14335
·
IF 14.511
Qihua Sun,Zhaofeng Wu,Zhangjie Qin,Xuan Chen,Chuanchuan Zhang,Biaobing Cao,Haiming Duan,Jun Zhang
Inspired by the similarity between the pleated structure of rose petals and the pleated structure of a dog's maxillary turbinate, porous biomass carbon materials with a pleated structure have been successfully prepared from rose petals by direct carbonization. Detailed SEM and TEM characterization showed that the carbonized rose tea (CRT) at 600 °C exhibited a mimetic structure very similar to the dog's maxillary turbinate. The trace K element was detected in the prepared CRT materials, which effectively improved the adsorption capacity of the CRT materials for NH3 as revealed by density functional theory based on first-principles calculations. As a result, the CRT sensor showed an ultra-high response (60.16k%) to 500 ppm NH3 with a theoretical detection limit of only 4.82 ppb, in addition to showing a fast recovery (2.0 s), excellent repeatability and long-term stability. Moreover, the formation of nanopores in the pleated structure of the CRT and the sensing mechanism of NH3 were analyzed. Through a simple, inexpensive and efficient method, this study provides a new strategy for the preparation of a high-performance gas sensor with a bionic structure by directly using the similarity between the biomass structure and dog nose structure.
研究领域:
材料科学
·
环境科学
·
仿生学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 37
·22780-22788
·
IF 3.361
Xiaoyi Sun,Qingjie Liu,Shuai Liu,Xintang Zhang,Shanshan Liu
A series of MOx–Cr2O3–La2O3/TiO2–N (M = Cu, Fe, Ce) catalysts with nitrogen doping were prepared via the impregnation method. Comparing the low-temperature NH3-SCR activity of the catalysts, CeCrLa/Ti–N (xCeO2–yCr2O3–zLa2O3/TiO2–N) exhibited the best catalytic performance (NO conversion approaching 100% at 220–460 °C). The physico-chemical properties of the catalysts were characterized by XRD, BET, SEM, XPS, H2-TPR, NH3-TPD and in situ DRIFTS. From the XRD and SEM results, N doping affects the crystalline growth of anatase TiO2 and MOx (M = Cu, Fe, Ce, Cr, La) which were well dispersed over the support. Moreover, the doping of N promotes the increase of the Cr6+/Cr ratio and Ce3+/Ce ratio, and the surface chemical adsorption oxygen content, which suggested the improvement of the redox properties of the catalyst. And the surface acid content of the catalyst increased with the doping of N, which is related to CeCrLa/TiO2–N having the best catalytic activity at high temperature. Therefore, the CeCrLa/TiO2–N catalyst exhibited the best NH3-SCR performance and the redox performance of the catalysts is the main factor affecting their activity. Furthermore, in situ DRIFTS analysis indicates that Lewis-acid sites are the main adsorption sites for ammonia onto CeCrLa/TiO2–N and the catalyst mainly follows the L–H mechanism.
研究领域:
催化
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2019
·
IF 5.128
Han Jiang,Bin Guan,He Lin,Zhen Huang
This study focuses on investigating the influence of Si/Al ratio on the performance of hydrothermally aged Cu/SSZ-13 catalysts prepared by in situ hydrothermal synthesis method. It was found that NH 3 -SCR performance and hydrothermal stability of Cu/SSZ-13 decreased with increasing Si/Al ratio. Fresh and hydrothermally aged Cu/SSZ-13 with Si/Al ratio of 6.5 showed the best SCR activity and N 2 selectivity in a broad temperature of 200–500 °C, in which more than 90% NO x was reduced with superior N 2 selectivity above 95%. The effect of Si/Al ratio on the properties of the physicochemical structure, the change of acidity intensity, and Cu species migration or transformation of the fresh and aged Cu/SSZ-13 catalysts were comprehensively characterized by NH 3 -TPO, NH 3 -TPD, H 2 -TPR, N 2 physisorption, XRD, ICP-AES, and XPS. The increase of the surface CuO species, the decrease of the amount of Cu 2+ in active sites, the chemisorption NH 3 species, the specific surface area, the total pore volume, and the increase of average pore diameter, may be the main reasons for performance deterioration over high-Si/Al-ratio catalysts after hydrothermal aging. Furthermore, in situ DRIFTS indicate that, with the increasing Si/Al ratio, the zeolitic structure was easy to collapse, and that the surface acid sites, the active copper species, as well as the adsorbed surface nitrate, decreased after hydrothermally aged. After hydrothermal aging, the amount of isolated Cu 2+ decreased, and more CuO species were aggregated, mainly coming from the conversion of the unstable isolated Cu 2+ species in D6R or CHA cages. The decrease of isolated Cu 2+ and CuO species aggregation were significant in Cu/SSZ-13 with high Si/Al ratios. The CuO leaded to the instability of the SSZ-13 skeleton structure and NH 3 oxidation promotion, resulting in catalysts deactivation.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Bo Song,Zhenxing Shen,Qingzhu Tian,Guiling Zhou,Qin Peng,Hao Fan,Jia Liu
Volcanic rock is a natural mineral with a porous structure and rich in various metal oxides. It has been used in environmental applications such as water and soil pollution remediation as stable chemical properties and low cost. In this work, volcanic rock was used in the field of nitrogen oxide control, and the feasibility of preparing NH 3 - Selective Catalytic Reduction catalyst was evaluated. The catalyst AVR-10Mn-450 was prepared by acidification-impregnation-calcination process, and it can achieve more than 90 % denitration effect at 175 °C, 25000 h −1 . It removes nitrogen oxides through the Eley–Rideal and Langmuir–Hinshelwood pathways. AVR-10Mn-450 has the advantages of simple preparation and low cost compared with the mainstream nano-denitration catalysts. It can be applied to the pretreatment of industrial flue gas such as cement plant or glass plant, thereby extending the service life of the precious metal or nano-catalyst at the back end. This work not only realizes the high-value resource utilization of volcanic rock, but also reduces the production cost of denitration catalyst.
研究领域:
环境科学
·
催化化学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2022
·
IF 13.7
Xiao-Chen Sun,Kun Yuan,Wang-De Hua,Zi-Rui Gao,Qian Zhang,Chen-Yue Yuan,Hai-Chao Liu,Ya-Wen Zhang
The metal–support interface plays a crucial role in heterogeneous catalysis. The modulation of the metal–support interaction (MSI) affords the possibility of promoting the catalytic efficiency per active site. Here, we report a strategy to modulate the interfacial interaction and then optimize the interfacial activity of Co/CeO2 catalysts for the water–gas shift reaction (WGSR) by a facile NH3 treatment process for the CeO2 support. The sample of Co/800N-CeO2 treated at 800 °C exhibited the highest reaction rate of 260 μmolCO/(gCo s), which was 23.8 times higher than the rate of the untreated Co/CeO2 sample. A combination of ex situ and in situ characterizations suggested that addition of the NH3 treatment process did not only weaken the metal–support interaction between the Co species and CeO2 support to strengthen CO adsorption and CO activation ability but also induced oxygen vacancy generation under reaction conditions to accelerate H2O activation. Both worked together in promoting the catalytic efficiency for the WGSR via the carboxyl pathway at a low temperature. It was worth mentioning that the N species of the CeO2 support introduced by the NH3 treatment was removed after changing the catalyst structure under reaction conditions. The interfacial structure was robust in a 60 h test at 400 °C due to the coexistence mechanism of carboxyl and formate pathways avoiding the poisoning effect of formate species on the active sites. The construction of active interfaces could be extended to Fe/CeO2 and Ni/CeO2 catalysts and could bring great promise in the design of the interfacial structure of supported catalysts in wide applications including chemical transformation reactions and industrial catalysis.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Yingying Jin,Kaihao Fan,Miao Feng,Yaoguang Wang,Hongfeng Chen,Xuesong Liu
This study investigates synergistic effects in Ni/CeO 2 catalysts for ammonia decomposition, comparing impregnation and mechanical mixing preparation methods. The impregnated catalyst achieved >90 % NH 3 conversion above 500 °C, outperforming Ni/SiO 2 and mixed counterparts. Strong interactions at the Ni-CeO 2 interface facilitated the formation of Ni-O-Ce bonds, lattice distortion, and oxygen vacancies (O v )/Ce 3+ species, enhancing Ni dispersion (34.7 nm vs. 73.1 nm) and electron transfer. Optimal NH 3 pretreatment (550 °C, 1.5 h) generated metallic Ni 0 as the primary active species, with higher Ni 0 content (XPS) and reducibility (H 2 -TPR). The novelty lies in establishing how NH 3 pretreatment dynamically assembles contiguous Ce 3+ -O v -Ni 0 triads. These sites facilitate rate-limiting N 2 desorption through localized electron donation from O v and Ce 3+ to Ni 0 , which weakens N-N bonds (NH 3 -TPD). Impregnation-derived synergy: (i) enhances Ni dispersion/reduction, (ii) promotes O v formation, and (iii) enables NH 3 -pretreatment-induced assembly of contiguous Ce 3+ -O v -Ni 0 triads that create electron-rich sites, lowering the activation barrier. This work provides a foundation for designing cost-effective catalysts via atomic-scale control of metal-support interactions.
研究领域:
催化
·
材料科学
·
化学工程
·
表面科学
·
环境科学
✓ 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）