Article
Chemistry, Multidisciplinary
Yali Liu, Yuenan Zheng, Danyang Feng, Liangliang Zhang, Ling Zhang, Xiaowei Song, Zhen-An Qiao
Summary: The study found that mesoporous Co3O4 catalyst exhibited excellent catalytic activity for the selective oxidation of aromatic alkanes, particularly the conversion of ethylbenzene to acetophenone with a conversion rate of 42% and a selectivity of 90% at 120 degrees Celsius. Furthermore, it was discovered that mCo(3)O(4) followed a unique catalytic pathway of direct oxidation from aromatic alkanes to aromatic ketones, as opposed to the conventional stepwise oxidation to alcohols and then to ketones. This implied that mCo(3)O(4) had a higher kinetic favorability for the direct oxidation of ethylbenzene to acetophenone compared to non-selective oxidation on commercial Co3O4.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Cristina Pizzolitto, Elena Ghedini, Somayeh Taghavi, Federica Menegazzo, Giuseppe Cruciani, Markus Peurla, Kari Eranen, Ivo Heinmaa, Atte Aho, Narendra Kumar, Dmitry Yu Murzin, Tapio Salmi, Michela Signoretto
Summary: The study focuses on improving the acidity of silica alumina composite using SBA-15, with modifications to enhance Lewis and Bronsted acidities, and introduction of alumina as a co-catalyst. The balanced acidities and proper porosity of the modified SBA-15 led to efficient performance in converting glucose to levulinic acid.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Chemistry, Physical
Peng Lu, Yue Yang, Jinwu Bai, Zilong Zhao, Min Fu, Xueli Hu, Youzhou He
Summary: Combining mesoporous structure and defect engineering is an effective strategy to enhance the photocatalytic activity of graphitic carbon nitride. The synthesized N-deficient mesoporous carbon nitride (nmpg-C3N4) exhibits superior photocatalytic purification of NO compared to bulk carbon nitride (B-C3N4), attributed to the increased active sites provided by the mesoporous structure and the improved redox ability resulting from the quantum confinement effect. The N defects in nmpg-C3N4 serve as catalytic active sites and facilitate the effective separation of photogenerated carriers. The synergistic effect of mesoporous structure and defect engineering enables nmpg-C3N4 to generate more center dot O2- and center dot OH species for NO removal, leading to a significantly higher photocatalytic activity of 60.61% compared to B-C3N4 (35.51%) and enhanced stability. The proposed NO purification path using in-situ DRIFTS technology provides valuable insights. This study demonstrates the potential of utilizing the quantum confinement effect of mesoporous materials combined with defect engineering for carbon nitride modification.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Zhi-Peng Han, Shiqi Wang, Qiming Sun, Xiao-Ping Xu, Shun-Jun Ji
Summary: A series of azoxy compounds were constructed via facile coupling reactions using cost-effective N-methoxyformamide and nitroso compounds over Cu-based catalysts, with high product yields and excellent tolerance of functional groups. A mesoporous silica nanosphere-encapsulated ultrasmall Cu (Cu@MSN) catalyst was developed and exhibited remarkably enhanced catalytic activity and superior recycling stability compared to copper salt catalysts. This work provides a green and efficient method for the construction of azoxy compounds and opens up new prospects for the application of nanoporous materials confined metal catalysts in organic synthesis.
Article
Chemistry, Applied
Meiyu Lv, Shengnan Song, Priyanka Verma, Meicheng Wen
Summary: In this study, Pd nanoparticles were successfully stabilized within hollow mesoporous aluminosilicate spheres, resulting in the synthesis of Pd/HMAS-1 catalyst. The catalyst exhibited excellent catalytic activity for toluene oxidation at a lower temperature compared to other catalysts, and also showed outstanding long-term stability. The confinement effect of ordered mesopores in stabilizing Pd nanoparticles, as well as improved mass transfer efficiency and accessibility to active Pd metal, contribute to the superior performance of Pd/HMAS-1.
Article
Multidisciplinary Sciences
Lucas Schneider, Khai That Ton, Ioannis Ioannidis, Jannis Neuhaus-Steinmetz, Thore Posske, Roland Wiesendanger, Jens Wiebe
Summary: By adjusting the resonance frequency of the quantum corral to the vicinity of the Fermi energy level, a pair of particle-hole symmetric states enters the gap of the superconductor, which can be explained by theoretically predicted Andreev bound states. These findings have direct implications for impurity-induced in-gap states in superconductors and provide insights into inducing superconductivity into surface states.
Article
Chemistry, Applied
Tao Liu, Xiaoqiu Ju, Zhixin Hu, Rongrong Xie
Summary: The confinement effect of ordered mesoporous SiO2 was found to effectively inhibit the aggregation of CoOx, promoting the formation of Co(III) species and enhancing the catalytic activity for CO oxidation. Additionally, the pore size of the carrier SBA-15 played a significant role in the catalytic activity of CoOx.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Physical
Wei Jiang, Huini Deng, Jie Liu
Summary: In this study, a hybrid photocatalyst was developed by grafting a cobalt molecular complex onto mesoporous carbon nitride, enabling efficient photocatalytic oxidation of organic molecules. This strategy offers a promising approach for oxidative reactions in photocatalytic chemical synthesis.
CATALYSIS COMMUNICATIONS
(2022)
Article
Environmental Sciences
Yueling Yu, Jia Yang, Xinfei Fan, Yanming Liu
Summary: Nitrogen-doped carbon materials (NMC) are commonly used in peroxymonosulfate-based advanced oxidation processes (PMSAOPs). Simply increasing the specific surface area and nitrogen content does not necessarily improve catalytic performance. Optimizing the pore structure of NMC is key to maximizing the catalytic performance. This study synthesized NMC with a mesopore structure that enhanced reactant diffusion and utilization of free radicals, resulting in improved removal efficiency of phenol.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Chemistry, Organic
Tobias E. Schirmer, Mehdi Abdellaoui, Aleksandr Savateev, Cyril Ollivier, Markus Antonietti, Louis Fensterbank, Burkhard Konig
Summary: Mesoporous graphitic carbon nitride (mpg-CN) is used as a photocatalyst for dual photoredox- and nickel-catalyzed cross-coupling reactions, enabling sustainable C(sp(2))-C(sp(3)) bond formation.
Article
Chemistry, Multidisciplinary
Fangfang Yang, Pierre Rousselot-Pailley, Cendrine Nicoletti, A. Jalila Simaan, Bruno Faure, Elise Courvoisier-Dezord, Agnes Amouric, Yolande Charmasson, Renal Backov, Thierry Tron, Yasmina Mekmouche
Summary: This study investigates the site-directed immobilization of a hybrid catalyst bearing a biquinoline-based-Pd(II) complex and a robust laccase within cavities of a silica foam to favor veratryl alcohol oxidation. The catalytic activity is dependent on the orientation and loading of each hybrid, and the system can be reused multiple times with a high operational activity remaining. The work demonstrates the concept of controlling the organization of a heterogeneous hybrid catalyst using a Pd/laccase/silica foam.
Review
Engineering, Environmental
Haoxi Dai, Ning Li, Jingya Ye, Jianhui Zhao, Xu He, Xiaoguang Duan, Beibei Yan, Guanyi Chen, Shaobin Wang
Summary: Recently, confined catalysts with large surface areas and adjustable pore and channel sizes have been used in advanced oxidation processes for water and wastewater treatment. In this review, the authors summarize the contaminant degradation behaviors in different confined catalytic systems, elaborate on the entire AOPs with confined catalysis, and provide suggestions and perspectives for the application of confined catalysis in AOPs.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Weijie Yang, Xiaoshuo Liu, Xuelu Chen, Yue Cao, Shaoping Cui, Long Jiao, Chongchong Wu, Chuanmin Chen, Dong Fu, Ian D. Gates, Zhengyang Gao, Hai-Long Jiang
Summary: A new single-atom catalyst Fe-1-N-4-C with excellent catalytic activity and sulfur resistance has been developed for the oxidation of NO and Hg-0, showing promising potential for cleaner coal-fired power plant operations.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Wang Ke, Xiangdong Qin, Robert M. Palomino, Juan Pablo Simonovis, Sanjaya D. Senanayake, Jose A. Rodriguez, Francisco Zaera
Summary: The redox properties of titania films grown by atomic layer deposition (ALD) on SBA-15 were investigated as a function of film thickness. Si-29 CP/MAS NMR and infrared absorption spectroscopy were used to determine the surface species formed during initial deposition and the transition from silica to titania surfaces. The reducibility of titania sites by CO and H-2 was studied ex situ using electron paramagnetic resonance (EPR) and in situ with ambient-pressure X-ray photoelectron spectroscopy (XPS). The results showed that the amorphous titania ALD films were more easily reduced and the reduction was reversible. The surface also exhibited a transition, with mixed Si-O-Ti sites forming in the early ALD cycles and a more typical titania surface developing as the film grew.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Review
Chemistry, Physical
Joanna Szymczak, Michal Kryjewski
Summary: The review highlights the use of heterogenic catalysts based on porphyrins and phthalocyanines loaded on mesoporous materials for oxidation reactions, with a focus on alkane, alkene, and arene substrates. Mesoporous silica is a promising candidate for anchoring macrocycles and obtaining new catalysts. The catalytic reactions studied are primarily aimed at producing epoxides, alcohols, ketones, aldehydes, or acids, with a particular interest in the oxidation of cyclohexane and cyclohexene. Some reactions exhibit biomimetic processes resembling those catalyzed by the cytochrome P450 enzyme family.
Article
Chemistry, Physical
Edwin Yik, David Hibbitts, Huamin Wang, Enrique Iglesia
Summary: Thiophene-H2 reactions proceed on dispersed metal nanoparticles via sulfur removal and hydrogenation routes, with reaction steps influenced by H2S/H2 ratios. Strong repulsion among S adatoms leads to partial surface coverage, creating interstitial spaces for catalytic turnovers.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Editorial Material
Chemistry, Applied
Nancy Artioli, Xiaolei Fan, Justin S. J. Hargreaves
Article
Chemistry, Physical
Enrique Iglesia, David Hibbitts
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Physical
Samuel L. Leung, David Hibbitts, Monica Garcia-Dieguez, Enrique Iglesia
Summary: Experimental and theoretical evidence suggests that H-2-D-2 isotopic equilibration occurs through non-competitive adsorption mechanisms at catalytic temperatures, without requiring recombinative desorption steps.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Shashikant A. Kadam, Andrew Hwang, Enrique Iglesia
Summary: This study investigates the effects of non-polar liquids on acetone aldol condensation reactions on TiO2 surfaces. The results show that non-polar liquids enhance reaction rates and selectivity by stabilizing transition states for adsorption and desorption. Additionally, solvation by non-polar liquids prevents the formation of larger oligomers, leading to slower deactivation of the catalyst.
Article
Chemistry, Physical
Trenton Otto, Xiaoyu Zhou, Stacey I. Zones, Enrique Iglesia
Summary: A synthetic procedure was developed for encapsulating Au nanoparticles within titanium silicalite-1 (TS-1), allowing for the assembly of TS-1 frameworks around Au coordination complexes. Changes to established crystallization procedures for TS-1 led to successful encapsulation of small Au nanoparticles, which showed catalytic activity for propene epoxidation.
JOURNAL OF CATALYSIS
(2022)
Article
Energy & Fuels
Cui Quan, Guangtao Zhang, Ningbo Gao, Sheng Su, Nancy Artioli, Dongdong Feng
Summary: This paper studied the migration, transformation, leaching toxicity, and risk assessment of heavy metals in oily sludge pyrolysis. The results showed that heavy metals were enriched in char and the leaching concentration of some heavy metals decreased after pyrolysis, while others increased. The findings also suggested that pyrolysis reduced the environmental risk of some heavy metals, but increased the risk of others.
Article
Chemistry, Physical
Ari F. Fischer, Enrique Iglesia
Summary: Support effects in alkene and arene hydrogenations on metal catalysts attributed to hydrogen spillover are caused by the desorption and hydrogenation of Pt-bound intermediates at acid-base pairs on certain oxides. Toluene-H2 reactions on Pt nanoparticles dispersed on SiO2 occur on surfaces with diverse coverages and reactivity, leading to preferential occupation by less reactive isomers. These less reactive species can desorb as methylcyclohexadiene molecules, which diffuse to nearby oxide surfaces and react, increasing the abundance of more reactive intermediates at Pt surfaces.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Andrew Hwang, Jason Wu, Andrew Bean Getsoian, Enrique Iglesia
Summary: Reduction-oxidation cycles in oxides are widely used in various applications and require coupling reactions at the surfaces of oxide crystals. CeO2-ZrO2 solid solutions (CZO) were used to study the kinetic relevance of surface reactions and diffusion in O-atom addition and removal. The experiments showed that O-removal rates depend on reductant pressures, while O-addition rates are similar for different reactants and can be affected by the presence of Pt nanoparticles.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Engineering, Chemical
Krutarth Pandit, Callum Jeffrey, John Keogh, Manishkumar S. Tiwari, Nancy Artioli, Haresh G. Manyar
Summary: Glycerol, a byproduct of biodiesel production, is a valuable feedstock produced in biorefineries. The esterification of glycerol with acetic acid produces a mixture of mono-, di-, and triacetins. Diacetin and triacetin, among the acetins, are considered important fuel additives with high energy density. The economic feasibility of producing diacetin and triacetin from glycerol has been studied, and the results indicate a positive gross profit and NPV for the project with a short payback period.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Enrique Iglesia, Haefa Mansour
Summary: Kinetic and isotopic measurements, along with theoretical assessments, were used to determine the identity and relevance of elementary steps and bound species in H-2-O-2 reactions on Pt surfaces. The reactions involve two kinetically-relevant O2 dissociation routes, one forming two bound O atoms on Pt atom ensembles within H* adlayers, and the other involving reactions with a H*-H* pair to form weakly bound hydrogen peroxide (*HOOH*). The results provide insights into the reaction mechanisms and can help improve catalytic processes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Nicholas R. Jaegers, Enrique Iglesia
Summary: Ni-based solids are effective catalysts for alkene dimerization, and the nature of their active centers and the identity and relevance of bound species and elementary reactions have been explored. A study shows that Ni centers grafted onto ordered MCM-41 mesopores lead to stable monomers that act as Lewis acid-base pairs and stabilize C-C coupling transition states. Density functional theory (DFT) treatments confirm the involvement of these active centers and pathways, which were not previously considered. The DFT-derived activation barriers for ethene dimerization are consistent with experimental measurements.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Environmental Sciences
Marina Maddaloni, Matteo Marchionni, Alessandro Abba, Michele Mascia, Vittorio Tola, Maria Paola Carpanese, Giorgio Bertanza, Nancy Artioli
Summary: In response to the EU's carbon neutrality initiative, water electrolysis for hydrogen production, particularly using Solid Oxide Electrolysis Cell (SOEC), is promising for decarbonizing energy systems. This study modeled a SOEC supplied with treated municipal wastewaters to determine the potential for green hydrogen production. By effectively evaporating and treating two wastewater streams, it was estimated that 26.2 kg/m(3) and 9.7 kg/m(3) of green hydrogen could be produced, contributing 0.4% to 20% of Italy's projected electricity demand by 2030.
Article
Environmental Sciences
Moses T. Yilleng, Nancy Artioli, David Rooney, Haresh Manyar
Summary: Palladium@mesoporous titania core@shell nanoparticles with uniform size distribution were synthesized using a four-component microemulsion system. These nanoparticles showed good absorption in both UV and visible regions, indicating their visible-light activity, which was not present in pristine TiO2 P25. The prepared 2%Pd@mTiO2 nanoparticles exhibited better photocatalytic performance for phenol degradation in visible light compared to conventional TiO2 P25 and 0.5%Pd/TiO2 P25 catalysts. Furthermore, the 2%Pd@mTiO2 catalysts demonstrated higher stability and reusability, with very high and stable phenol degradation in continuous flow over 52 hours. This study highlights the potential application of these catalysts for phenol degradation and wastewater treatment.
Article
Energy & Fuels
Jamilu Salisu, Ningbo Gao, Cui Quan, Jale Yanik, Nancy Artioli
Summary: This study presents a novel model for simulating the co-gasification of rice husk and plastic using Aspen Plus. The model utilizes an artificial neural network (ANN) to predict the pyrolysis process involved in gasification, resulting in a more realistic model. Three ANN models were developed, using inputs of ultimate analysis, higher heating value, and pyrolysis temperature. The developed models showed good agreement with actual data and achieved a maximum hydrogen content of 69.42 vol% at 750 degrees C, with a least root mean square error of 2.62.
JOURNAL OF THE ENERGY INSTITUTE
(2023)
