Journal of CO2 Utilization
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2020
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IF 5.993
Zijie Shi,Qian Su,Ting Ying,Xin Tan,Lili Deng,Li Dong,Weiguo Cheng
Synthesis of cyclic carbonates via cycloaddition reaction by means of CO 2 and epoxides has been thought as an effective method for relieving global warming together with resource shortage. In order to elevate the utilization ratio of ionic liquids and separate catalysts easily after reaction, multi-site ionic liquids were designed and then immobilized on SBA-15 for the conversion of CO 2 into cyclic carbonates. By combining the advantages of multiple sites and mesoporous channel, in this work, a certain amount of ionic liquids with multiple active sites were firmly immobilized on modified SBA-15. Among all the immobilized ionic liquids, [IMCA] 2 Br 2 @SBA-15 presented the best catalytic activity. The result showed high yield (97.4 %) and almost 100 % selectivity of propylene carbonate, which was close to equivalent molar bulk ionic liquids. This superiority could be attributed to the sufficient dispersion of multiple active sites of ionic liquids after being immobilized, enabling efficient use of ionic liquids. Furthermore, the catalyst showed good recyclability after five cycles. By characterization and DFT calculation, the synergistically catalytic mechanism based on multiple sites was proposed.
研究领域:
化学工程
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催化化学
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环境科学
✓ 已验证
DOI
高影响因子
ACS Catalysis
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2024
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IF 11.3
Zhongyao Zhang,Feiting Zhang,Zhongxin Song,Lei Zhang
Metal-free carbon materials functionalized with pyridinic nitrogen groups exhibit promising electrocatalytic activity for the oxygen reduction reaction (ORR). However, not all pyridinic nitrogen groups are equally active for the ORR, which remains ambiguous and requires rigorous quantification and differentiation by their basicity. Here, we introduce the potentiometric titration method for identifying and quantifying nitrogen-containing groups on carbon materials by their Lewis basicity and reactivity in characteristic tests. Various carbon materials are functionalized with nitrogen heteroatoms. Potentiometric titration, X-ray photoelectron spectroscopy (XPS), and elemental analysis suggest that a significant amount of pyridinic nitrogen groups are buried within the bulk structures and cannot be accessed by protons and oxygen molecules. Besides, pyridinic nitrogen functions located adjacent to other nitrogen atoms exhibit weaker basicity due to strong inductive or resonance effects, resulting in a negligible contribution to the ORR activity. ORR measurements under alkaline conditions suggest that the titratable pyridinic nitrogen groups are essential for the active site (or site pair), and kinetic current density is directly proportional to the density of titratable pyridinic nitrogen groups. Furthermore, the turnover frequency for the ORR increases with the Lewis basicity of the pyridinic nitrogen groups for all investigated carbon materials in alkaline and acidic conditions. Density functional theory (DFT) calculations suggest that the ORR occurs on the carbon atoms adjacent to pyridinic nitrogen groups. Pyridinic nitrogen with a higher Lewis basicity can affect adjacent carbon atoms more efficiently, which stabilizes the key intermediates for the ORR and decreases the activation barrier. This work provides an informative and convenient way for characterizing nitrogen-containing groups on carbon materials, especially in quantifying the active pyridinic nitrogen sites for the ORR.
研究领域:
电化学
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催化科学
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材料科学
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
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2020
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IF 5.825
Rong Wang,Chizhong Wang,Sihan Yin,Yue Peng,Jianjun Chen,Yanxi Deng,Junhua Li
Nickel iron (oxy)hydroxide (NiFeO x H y ) is among the most active electrocatalysts for oxygen evolution reaction (OER) in the alkaline media. Development of new design strategy for NiFeO x H y electrode with respect to intrinsic activity and number of active species is highly attractive. Here we report a hierarchical fabrication for NiFeO x H y electrode towards efficient oxygen evolution. Three-dimensional mesoporous NiO was initially prepared and reduced to a polycrystalline Ni metal framework. Despite the poor OER activity for Ni-based catalyst, the incorporation of surface Fe species induced a notably high current density for the oxygen evolution. The results indicated that the Fe species, located at outer surface region, played a key role as the OER active sites. It is also found that the surface of metallic Ni was reconstructed to (oxy)hydroxide phase with ease compared to NiO. As a result, a heterostructure composed of an OER-active NiFe (oxy)hydroxide shell and an electron-conductive Ni core was formed. In this fabricated NiFeO x H y /Ni catalyst, the promoted intrinsic activity, number of active sites and charge-transfer ability all taken into account contribute to an efficient OER process.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2023
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IF 7.3
Yuxin Chen,Binhang Yan,Yi Cheng
The catalytic performance of the non-purified MoVNbTeO x catalyst was optimized by changing the composition of the synthesis gel method in the hydrothermal synthesis process. However, the enhancement in activity was more pronounced for the post-treatment process of the non-purified catalyst. The catalytic performance of non-purified MoVNbTeO x catalysts and phase-pure M1 catalysts in the oxidative dehydrogenation of ethane (ODHE) were enhanced by water agitation post-treatment. The results showed that the phase-pure M1 catalyst obtained by treating the MoVNbTeO x catalyst with nitric acid had an increased activity per unit mass, but with a mass loss of catalyst materials during the purification process. After several days of post-treatment with water agitation, the catalytic activity of the non-purified MoVNbTeO x and the M1 samples gradually increased and stabilized, where both catalysts had a comparable catalytic performance. All the samples were systematically characterized, showing that the catalytic performance of the samples was mainly correlated with the enhanced specific surface area/pore volume. The results show that for the hydrothermally synthesized MoVNbTeO x catalysts, the reaction takes place in the micropores and the key to improve the performance of MoVNbTeO x catalysts is to effectively expose the active sites. Physical post-treatment process that does not require nitric acid or hydrogen peroxide for purification is also effective in enhancing catalyst activity by boosting the active site.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Yasir Abbas,Sajjad Ali,Majid Basharat,H.M. Adeel Sharif,Muhammad Ahsan Iqbal,Mohamed Bououdina,Haoliang Wang,Niaz Ali Khan
The sustainable recovery of gold from electronic waste (E-waste) remains a significant challenge due to lack of multiple redox active-sites in the existing adsorbents, their high cost, and poor stability in extreme acidic conditions. Herein, we rationally designed the skeleton engineering of poly(organo)phosphazene via substitution reaction of hexachlorocyclotriphosphazene (HCCP) with p-phenylenediamine (DA), 1,4-benzenedithiol (DT), and 4-aminothiophenol (AT), producing poly(p-phenylenediamine-co-cylotriphosphazene) (PDA) with N-redox active-sites, poly(1,4-benzenedithiol-co-cylotriphosphazene) (PDT) containing S-redox active-sites, and poly(4-aminothiophenol-co-cylotriphosphazene) (PAT) holding dual N-S-redox active-sites. The PDA, PDT, and PAT in the N-bromosuccinimide/pyridine (NBS/Py) leaching solution demonstrated extraction efficiency of 83.7 % Au 3+ , 45.5 % Cu 2+, 44 % Ni 2+ , and 83.6 % Au 3+ , 47.4 % Cu 2+ , 48 % Ni 2+ , and 83.1 % Au 3+ , 48.5 % Cu 2+ , 48.8 % Ni 2+ . While, in the aqua regia, these adsorbents showed extraction efficiency of 70.0 % Au 3+ , 14.0 % Cu 2+ , 13.8 % Ni 2+ , and 92.3 % Au 3+ , 6.4 % Cu 2+ , 9.8 % Ni 2+ , and 95.6 % Au 3+ , 13.0 % Cu 2+ , 10.3 % Ni 2+ . In particular, the PAT with the dual N-S-redox active sites achieved maximal Au 3+ extraction efficiency (99.2 %), which is 1.05 and 1.04 times higher than PDA and PDT within 15 min, superb uptakes of 2000 mg/g, excellent selectivity (99.9 %) in a mixture of eight metal ions (Al, Co, Cu, K, Mg, Na, Ni, Mn), 100 % removal capacity and high stability even in pure aqua regia leaching solution. Gold ions adsorbed on these adsorbents, spontaneously reduced, experienced nucleation, and grew into single crystalline nanoplates along (111) planes as well as nanolayers composed of Au-single-atoms and Au-nanoclusters. The density function theory (DFT) calculations and variation in binding energies of N and S indicated that due to the synergy of dual N-S-redox active-sites, the PAT showed enhanced performances and excellent selectivity. For commercial applications, the as-synthesized PDA, PDT, and PAT were highly stable in pure aqua regia leaching solution, showing precisely selective and rapid gold extraction (70 %, 92 %, 96 %, respectively) than N- NBS/Py leaching systems (83 %) with traces of other competing metals. This study proves that skeleton-modulated poly(organo)phosphazene greatly facilitates gold extraction for industrial-scale applications.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
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2024
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IF 4.4
Meng Zhang,Ying Zhang,Qianglong Xu,Xiaolan Li,Jing Chen,Hongpeng Jia
Energy shortage and environmental pollution problems force us to find low-energy consume methods to deal with volatile organic compounds (VOCs). In this work, Pt-P25 was synthesized through a simple wet impregnation method and calcination method. The study showed that different calcination temperatures and calcination atmospheres affected the activation state of Pt species, showing significant differences in the photothermal catalytic toluene oxidation reaction efficiency. The Pt-P25-800N sample activated in a nitrogen atmosphere at 800 oC exhibits better activity compared to other samples, achieving a toluene conversion rate of 95% and a mineralization rate of 65% under a light intensity of 400 mW/cm2. Characterization results demonstrate that low-valent Pt species are positively correlated with toluene oxidation activity and play a major role in the reaction. The ultraviolet (UV), visible (Vis) and infrared (IR) components in the spectrum all contribute to the toluene oxidation process. The catalytic bed is heated to the required temperature mainly through thermal effects and crosses the reaction energy barrier. The traditional photocatalytic process over TiO2 also plays an auxiliary enhancement role. Due to the efficient conversion capability of the active sites, Pt-P25-800N achieves long-term stability of at least 50 hours under low light intensity input and water vapor conditions, accompanied by minimal accumulation of intermediate products. The above results explain that the comprehensive effect between active Pt species and photothermal catalysis jointly achieves efficient degradation of VOCs and alleviates the energy and environmental crisis.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Huanmin Liu,Jiayi Peng,Xu Zhang,Kun Zheng,Lirong Zheng,Kangle Lv,Qin Li,Peng Zhou
Employing water and biomass fuels, such as benzyl alcohol, as feedstocks for co-producing hydrogen (H 2 ) and value-added organic chemicals under solar irradiation presents a promising strategy towards accomplishing net-zero emission objectives. However, simultaneously building the optimal hydrogen-evolution and organic-dehydrogenation centers on photocatalyst surface has long been the pursuit. Herein, a facile vacancy-based strategy was utilized to engineer atomically dispersed Pt species coordinated with three foreign ligand nitrogen atoms (Pt-N 3 ) instead of intrinsic S atoms on CdS nanorods. The experimental observation demonstrates a distinctive electron-rich characteristics of Pt-N 3 structure, markedly augmenting the photogenerated charge separation efficiency via one interfacial charge effects. The density functional theory (DFT) simulation further indicates that the foreign ligand N atoms not only maintain the low hydrogen-evolution energy barrier of Pt center, but also greatly reduce the energy barrier of rate-determining benzyl alcohol dehydrogenation by forming the strong chemical interaction between ligand N atom and intermediate. Consequently, PtN 3 -CdS exhibited a high photocatalytic activity for coproduction of H 2 (5.4 mmol g −1 h −1 ) and benzaldehyde (5.2 mmol g −1 h −1 ) with a selectivity of 95.9% for value-added benzaldehyde, with the anticipation of bolstering its commercial accessibility and expediting its integration into industrial applications.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Energy Storage Materials
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2025
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IF 20.2
Nengbiao Zhang,Luming Yin,Letian Chen,Bingbing Ma,Yuantonghe Li,Xinyi Zhang,Junqing Liu,Zhen Zhou
Abstact Lithium-nitrogen (Li-N 2 ) battery is not only an electrochemical energy storage platform, but also an environmentally friendly nitrogen fixation technology. However, a great challenge remains in regulating catalyst activity to accelerate cathode reaction kinetics. Herein, we proposed an oxygen vacancy-mediated modulation of Fe active sites in FeO x nano-particle catalysts and Fe single-atom catalysts to enhance nitrogen reduction reaction in Li-N 2 batteries. High-concentration oxygen vacancy is generated through a size- and crystallinity-dependent oxygen vacancy engineering based on the precise atomic layer deposition of reducible oxides. The oxygen vacancy on FeO x drives the electron redistribution of Fe 3+ d-orbitals to provide electron-donating Fe active sites for N 2 fixation. Meanwhile, oxygen vacancy-rich MoO y is used as a support to anchor Fe single atoms. Adjacent oxygen vacancy drives the stable coordination between Fe single atoms and O atoms to facilitate the directional electron transfer from MoO y to Fe to N 2 . Therefore, the Li-N 2 batteries exhibit large discharge capacity, excellent rate performance, and reliable cycle stability. In addition, the formation and decomposition of the discharge product Li 3 N indicate a reversible N 2 fixation. This work provides a precise regulation mechanism of catalytic active sites based on oxygen vacancy engineering, which is expected to promote the development of high-performance Li-N 2 batteries.
研究领域:
材料科学
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电化学
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the American Chemical Society
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2024
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IF 14.4
Yanliang Zhou,Lili Liang,Congying Wang,Fuxiang Sun,Lirong Zheng,Haifeng Qi,Bin Wang,Xiuyun Wang,Chak-tong Au,Junjie Wang,Lilong Jiang,Hideo Hosono
To date, NH3 synthesis under mild conditions is largely confined to precious Ru catalysts, while nonprecious metal (NPM) catalysts are confronted with the challenge of low catalytic activity due to the inverse relationship between the N2 dissociation barrier and NHx (x = 1–3) desorption energy. Herein, we demonstrate NPM (Co, Ni, and Re)-mediated Mo2CTx MXene (where Tx denotes the OH group) to achieve efficient NH3 synthesis under mild conditions. In particular, the NH3 synthesis rate over Re/Mo2CTx and Ni/Mo2CTx can reach 22.4 and 21.5 mmol g–1 h–1 at 400 °C and 1 MPa, respectively, higher than that of NPM-based catalysts and Cs–Ru/MgO ever reported. Experimental and theoretical studies reveal that Mo4+ over Mo2CTx has a strong ability for N2 activation; thus, the rate-determining step is shifted from conventional N2 dissociation to NH2* formation. NPM is mainly responsible for H2 activation, and the high reactivity of spillover hydrogen and electron transfer from NPM to the N-rich Mo2CTx surface can efficiently facilitate nitrogen hydrogenation and the subsequent desorption of NH3. With the synergistic effect of the dual active sites bridged by H-spillover, the NPM-mediated Mo2CTx catalysts circumvent the major obstacle, making NH3 synthesis under mild conditions efficient.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Xiaosong Zhou,Xiaoxing Yu,Lanzhen Peng,Jin Luo,Xiaomei Ning,Xuliang Fan,Xunfu Zhou,Xiaoqin Zhou
The photocatalytic H 2 production activity of polymer carbon nitride (g-C 3 N 4 ) is limited by the rapid recombination of photoelectron-hole pairs and slow surface reduction dynamic process. Here, a supramolecular complex (named R-TAP-Pd(II)) was fabricated via self-assembly of (R)-N-(1-phenylethyl)-4-(4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)benzamide (R-TAP) with Pd(II) and used to modify g-C 3 N 4 . In the R-TAP-Pd(II)@g-C 3 N 4 composite photocatalyst, the spin polarization of R-TAP-Pd(II) can promote charge transfer and inhibit photogenerated carrier recombination, as confirmed by spectral tests and photoelectrochemical performance tests. Electrochemical tests and in situ X-ray photoelectron spectroscopy (XPS) tests proved that the Pd(II) ion in the R-TAP-Pd(II) molecule can serve as active sites to accelerate H 2 production. The R-TAP-Pd(II)@g-C 3 N 4 presented a photocatalytic H 2 generation rate of 1085 μmol g −1 h −1 when exposed to visible light, which was a about 278-fold increase compared with g-C 3 N 4 . This work finds a new approach to boost the photocatalytic efficiency of g-C 3 N 4 via supramolecular self-assembly.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of CO2 Utilization
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2024
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IF 7.2
Luqman Abdullahi Sani,Haolong Bai,Zifu Xu,Liangliang Fu,Yining Sun,Xiaorui Huang,He Gao,Xuejing Liu,Dingrong Bai,Zhanguo Zhang,Fabing Su,Jiao Liu,Guangwen Xu
Ni/Al 2 O 3 catalysts (noted as Ni/Al-350, Ni/Al-500, and Ni/Al-700, respectively) were synthesized by a facile solution combustion method but at different combustion temperatures (350 °C, 500 °C, and 700 °C, respectively). For comparison, Ni/Al 2 O 3 (noted as Ni/Al-100) was also prepared by the impregnation method and applied in the methanation reaction. The Ni/Al 2 O 3 synthesized at the combustion temperature of 350 °C showed better performance than the others at higher combustion temperatures, and the activity for CO 2 methanation followed an order of Ni/Al-350 > Ni/Al-500 > Ni/Al-700 > Ni/Al-100. The increase in the combustion temperature decreased active sites for the H 2 and CO 2 adsorption, which could be associated with the reduced Ni dispersion and basic sites, thus lowering its activity and increasing its carbon deposition rate.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Mingshuo Tian,Zhiwei Huang,Jiangwei Ni,Wen Chen,Qiqi Zhou,Huazhen Shen,Xiaomin Wu,Huawang Zhao,Guohua Jing
The elucidation of active sites in Pt-based catalysts for benzene combustion has been a long-standing challenge, hindering the rational design of such catalysts. We have successfully pinpointed the active sites to the perimeters of Pt nanoparticles, deliberately excluding corner atoms. This achievement stems from a comprehensive approach, encompassing controlled synthesis of Pt nanocrystal size and morphology, advanced spectroscopic characterization, and detailed geometrical model analysis. We synthesized well-defined truncated hexahedral Pt nanoparticles with diameters (d) ranging from 2.2 to 6.6 nm. Notably, the turnover frequency (TOF) of our Pt/TiO 2 catalyst correlates inversely with the nanoparticle diameter, following a d -1.09±0.11 trend. This correlation matches the model-predicted perimeter-to-diameter ratio (excluding corners) with a d -1.01±0.09 exponent, confirming the location of the active sites. Further support comes from X-ray photoelectron spectroscopy and experiments using different support materials, which underscore the high activity at the Pt/TiO 2 interface. A crucial H 2 treatment step encapsulating the Pt nanoparticles by TiO x excludes both surface areas and corners as contributing active sites. The 0.7 % Pt/TiO 2 catalyst also demonstrated remarkable stability under testing conditions. In situ FTIR analysis provided insight into the stepwise mechanism of benzene combustion, revealing intermediate species and their transformation pathways. By finely tuning the geometry of Pt nanoparticles and correlating TOF with specific surface sites, our research highlights the perimeters of Pt atoms as the prime active sites for benzene combustion. These results contribute significantly to the field, offering a strategic approach to designing efficient catalysts for VOC elimination, with implications for both environmental protection and the advancement of catalytic science.
研究领域:
催化科学
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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）