Review
Chemistry, Physical
Shangkun Li, Rizwan Ahmed, Yanhui Yi, Annemie Bogaerts
Summary: This review summarizes the latest advances in heterogeneous catalysis and plasma catalysis for direct oxidation of methane to methanol (DOMTM), aiming to point out the differences between the two and provide insights into their reaction mechanisms, as well as implications for future development of highly selective catalysts for DOMTM.
Article
Chemistry, Multidisciplinary
Huizhen Zhang, Wanfu Zhong, Qiaobin Gong, Pengfei Sun, Xiaozhen Fei, Xuejiao Wu, Sha Xu, Qinghong Zhang, Gang Fu, Shunji Xie, Ye Wang
Summary: We constructed a solar-energy-driven redox cycle using iron ions as catalysts for the combination of CH4 conversion and H2 production. A photo-driven iron-induced reaction system was developed, which showed high efficiency in the selective coupling of CH4, benzene, and cyclohexane under mild conditions. Mechanistic studies revealed that CH4 coupling was induced by hydroxyl radical generated by photo-driven intermolecular charge migration of an Fe3+ complex. The produced Fe2+ was used to reduce the potential for electrolytic H2 production and then turned back into Fe3+, forming an energy-saving and sustainable recyclable system.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Yinjie Ji, Andrea N. Blankenship, Jeroen A. van Bokhoven
Summary: Methane conversion strategies that protect methanol achieve higher yields compared to direct conversion, but most of these systems operate under unfavorable conditions. Limited work has been done on developing heterogeneous catalysts for methane-to-methyl-ester conversion, specifically with manganese catalysts. This study demonstrates the activity of silica-, titania-, and zirconia-supported manganese catalysts for methane conversion and identifies silica as the most effective support.
Article
Chemistry, Physical
Yinjie Ji, Andrea N. Blankenship, Jeroen A. van Bokhoven
Summary: Methane conversion strategies with in situ esterification achieve higher yields but operate under unfavorable conditions. Limited research has been done on heterogeneous catalysts for methane-to-methyl-ester conversion and on the activity of manganese for methane conversion. This study demonstrates the activity of silica-, titania-, and zirconia-supported manganese catalysts for methane-to-methyl-ester conversion and shows that silica-supported catalyst exhibits high overall activity.
Article
Chemistry, Multidisciplinary
Xilan Feng, Dapeng Liu, Baolin Yan, Mingzhe Shao, Zhimin Hao, Guobao Yuan, Haohan Yu, Yu Zhang
Summary: By triggering the aqueous auto-redox reactions between reductive Ce(OH)(3) and oxidative MnO4-/Pd2+ ions, PdO/Mn3O4/CeO2 (PMC) nanocomposites were formed, showing strong synergistic effects. The HPMC nanocomposites exhibited excellent performance in photoassisted thermal catalytic CH4 combustion, with a reduced light-off temperature of 180 degrees C under visible light irradiation. The catalytic reaction process followed the classic MVK mechanism, with O-2 adsorption/activation into active oxygen species (O*) being the rate-determining step for CH4 conversion.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Hyesung Lee, Choah Kwon, Sekar Vikneshvaran, Sukjun Lee, Sang-Yup Lee
Summary: In this study, a single-atom Cu catalyst supported on amorphous carbon was prepared for direct methane partial oxidation. Carbonization of Cu-doped ZIF-8 resulted in the implantation of single-atom Cu active centers on the amorphous N-doped carbon. The prepared catalyst exhibited high selectivity and stability for methane oxidation.
APPLIED SURFACE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Yanyan Zhao, Sheng Dai, Ke R. Yang, Sufeng Cao, Kelly L. Materna, Hannah M. C. Lant, Li Cheng Kao, Xuefei Feng, Jinghua Guo, Gary W. Brudvig, Maria Flytzani-Stephanopoulos, Victor S. Batista, Xiaoqing Pan, Dunwei Wang
Summary: Atomically dispersed catalysts have shown high activity for selective oxidation of carbon monoxide with excess hydrogen, but their stability is not ideal. This study demonstrates that introducing a structural component to minimize the diffusion of the active metal center significantly improves stability without compromising activity. By using a dinuclear iridium heterogeneous catalyst as a study platform, two types of oxygen species, interfacial and bridge, are identified to work together for both activity and stability. This work provides important insights into the synergistic effect between the active metal center and the supporting substrate, with potential broad applications for atomically dispersed catalysts.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Physical
Zhi Liu, Guangyan Xu, Lingyou Zeng, Wei Shi, Yingjie Wang, Yanwei Sun, Yunbo Yu, Hong He
Summary: We prepared a PtPd-La1/Al2O3 catalyst with highly dispersed La species and Pt-PdO nanoparticles, showing significantly enhanced hydrothermal and long-term stability under the harsh conditions of simulated natural gas vehicle (NGV) exhaust. PdO nanoparticles can be anchored by highly dispersed La sites through electron transfer, inhibiting the sintering of Pd species during hydrothermal aging. Pt uniformly doped in PdO creates high-efficiency Pt sites and unsaturated Pd sites for water-resistance, further enhancing long-term stability. This work provides the potential to resolve tough challenges related to methane emission control on NGVs.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Jianlong Yang, Chao Wang, Jialiang Xing, Junwang Tang
Summary: This study presents a strategy for the continuous transformation of methane to ethane with high activity and remarkable selectivity using Pd decorated anatase as the catalyst. The optimized Pd1.8-TiO2 catalyst shows a high ethane yield of 40.9 μmol/h, which is 13 times higher than that of bare TiO2, and an ethane selectivity of 80.4%, comparable to previous benchmarks. In situ characterizations reveal that Pd nanoparticle functions as a hole acceptor, facilitating charge separation and significantly improving the performance of photocatalytic partial oxidation of methane.
SURFACES AND INTERFACES
(2023)
Article
Engineering, Environmental
Chun-Yu Lai, Mengxiong Wu, Xuanyu Lu, Yulu Wang, Zhiguo Yuan, Jianhua Guo
Summary: This study demonstrates that microbially reducing perchlorate in groundwater can be driven by ethane or propane under oxygen-limiting conditions, offering a cost-effective strategy for ex situ groundwater remediation. Analysis of transcript abundance and high-throughput sequencing revealed the key microorganisms involved in the process.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Multidisciplinary Sciences
Cedric J. Hahn, Olivier N. Lemaire, Joerg Kahnt, Sylvain Engilberge, Gunter Wegener, Tristan Wagner
Summary: The study reveals the high-resolution structure of an ethane-activating enzyme and its distinguishing features from other enzymes, such as a widened catalytic chamber and a sulfur replacing oxygen as the lower-axial ligand. A long hydrophobic tunnel guides ethane to the buried active site.
Review
Chemistry, Physical
Zengzan Zhu, Wenyi Guo, Ying Zhang, Chengsi Pan, Jing Xu, Yongfa Zhu, Yang Lou
Summary: This review highlights the importance of methane conversion into value-added chemicals, discusses the advanced photothermal synergetic strategy for efficient methane conversion, as well as the methane direct conversion through photocatalysis and thermocatalysis.
Article
Chemistry, Physical
Jiaojiao Song, Yixuan Yang, Shoujie Liu, Lei Li, Nan Yu, Yuteng Fan, Zhiming Chen, Long Kuai, Baoyou Geng
Summary: This study investigates the impact of dispersion and support on the activity of Pt in CO oxidation reaction, revealing that reducible TiO2 significantly influences Pt activity with lower apparent activation barriers, and that single-atom dispersion of Pt maximizes active sites.
Article
Chemistry, Multidisciplinary
Karoline Kvande, Sebastian Prodinger, Bjorn Gading Solemsli, Silvia Bordiga, Elisa Borfecchia, Unni Olsbye, Pablo Beato, Stian Svelle
Summary: Cu-zeolites can activate the C-H bond of ethane and produce ethylene with high selectivity at 150 degrees C in a cyclic protocol. The ethylene yield is influenced by both the zeolite topology and Cu content. Ethylene adsorption studies suggest that oligomerization of ethylene occurs over protonic zeolites but not over Cu-zeolites. We propose that this observation is due to the formation of an ethoxy intermediate.
CHEMICAL COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Yingchun Li, Linyi Li, Shizhong Luo, Xianbo Huang, Jun Shen, Chengfa Jiang, Fangli Jing
Summary: The addition of K into Cr-based catalysts improves catalytic stability and ethylene selectivity in the oxidative dehydrogenation of ethane with CO2. The presence of K enriches surface Cr6+ and oxygen species, enhancing surface basicity and facilitating the desorption of ethylene, leading to improved productivity within a reaction time of 50 hours.
ADVANCED COMPOSITES AND HYBRID MATERIALS
(2021)
Review
Chemistry, Multidisciplinary
Jun Kyu Kim, Sangwoo Kim, Seunghyun Kim, Hyung Jun Kim, Kyeounghak Kim, WooChul Jung, Jeong Woo Han
Summary: Metal oxide surfaces undergo spontaneous reorganization during reactions, complicating the understanding of reaction mechanisms and material properties. This review categorizes the surface reorganization into three types and summarizes their effects on different reactions, providing novel insights for the design of metal-oxide-based catalytic materials.
ADVANCED MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Hyunwoo Yook, Jinwoo Hwang, Woonsuk Yeo, Jungup Bang, Jaeyoung Kim, Tae Yong Kim, Jae-Soon Choi, Jeong Woo Han
Summary: Hydroxyapatite (HAP) is a versatile green catalyst with high flexibility and multifunctionality. Various modification methods such as ionic composition change, morphology control, incorporation of other metal species, and catalytic support engineering have been explored for improving its catalytic performance. However, systematic design strategies for HAP catalysts are still lacking due to incomplete understanding of structure-activity relationships. This review discusses the methods of modulating HAP and investigates the mechanisms and effects of structural changes on catalytic performance, along with computational studies and future research directions.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Sanghyeok An, Ziang Wu, Hayoung Jeong, Juhyeok Lee, Sang Young Jeong, Wonjong Lee, Sunkyu Kim, Jeong Woo Han, Jongchul Lim, Hyojung Cha, Han Young Woo, Dae Sung Chung
Summary: This study explores the importance of hydrophilicity and backbone planarity in polymer photocatalysts, focusing on a series of benzothiadiazole-based donor-acceptor alternating copolymers with alkoxy, linear oligo(ethylene glycol) (OEG) side chains, and backbone fluorine substituents. The results show that OEG side chains improve the interaction with water and enable electron transfer to water. Additionally, fluorine substituents on the backbone produce highly ordered lamellar stacks and long-lived polarons. A new nanoparticle synthesis strategy using a methanol/water mixed solvent is also introduced, avoiding the screening effect of surfactants. The copolymer with OEG side chains and fluorine substituents achieves a high hydrogen evolution rate under visible-light irradiation. This study demonstrates the optimization of glycol side chain strategy for polymer photocatalysts.
Article
Nanoscience & Nanotechnology
Selvaraj Seenivasan, Kyu In Shim, Chaesung Lim, Thangavel Kavinkumar, Amarnath T. Sivagurunathan, Jeong Woo Han, Do-Heyoung Kim
Summary: In this study, a Ni-Co-Mo sulfide with improved pseudocapacitive charge storage mechanism is demonstrated as a promising candidate for high energy density supercapattery devices. By adding a classical Schottky junction next to the electrode-electrolyte interface, the pseudocapacitive behavior is enhanced, resulting in a specific capacity of 2,114 C g(-1) at 2 A g(-1) for the negative electrode, matching that of the positive electrode at 3 A g(-1). With the equivalent contribution from both electrodes, an energy density of 236.1 Wh kg(-1) is achieved at a power density of 921.9 W kg(-1) with a total active mass of 15 mg cm(-2).
NANO-MICRO LETTERS
(2023)
Article
Robotics
Jeong-woo Han, Soo Jeon, Hyock Ju Kwon
Summary: One way to construct a global path for a mobile robot is to extract equidistant points from obstacles in an occupancy grid map (OGM) as its backbone of thin lines (skeleton) and find an appropriate path from them. This paper introduces hierarchical topology map with explicit corridor (HTM-EC) as a new skeleton-based strategy for global path planning with path optimization.
INTELLIGENT SERVICE ROBOTICS
(2023)
Article
Chemistry, Physical
Jihyeon Lee, Byung Gwan Park, Kiheon Sung, Hyeongeon Lee, Jihun Kim, Eonu Nam, Jeong Woo Han, Kwangjin An
Summary: This study investigates the reversible hydrogenation and dehydrogenation processes in a liquid organic hydrogen carrier (LOHC) system using a single-catalyst approach. Key hydrogen-involved catalytic behaviors, such as adsorption and migration, play crucial roles in reactivity. The findings demonstrate that employing a defective metal oxide support can facilitate these behaviors at the active sites on the catalyst surface during the LOHC process.
Article
Chemistry, Multidisciplinary
Kwanyong Jeong, Sunil Kwon, Hyunwoo Yook, Jeong Jae Lee, Ju Seong Lee, Myungho Choi, Hyung Seob Lim, Sang-Joon Kim, Soo Min Kim, Jeong Woo Han, Ji Hoon Park
Summary: Liquid organic hydrogen carrier (LOHC) technology enables safe and convenient storage and transportation of hydrogen in large quantities. This study proposes a promising LOHC candidate, 1-(n-phenylethyl)naphthalene (PEN), which exhibits high hydrogen storage capacity, superior physical properties, and low cost. PEN showed reversible hydrogen storage and release performance, and the dehydrogenation performance can be enhanced by controlling the composition of stereo isomers.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Physical
Su-Hyun Yoo, Leonardo Shoji Aota, Sangyong Shin, Ayman A. El-Zoka, Phil Woong Kang, Yonghyuk Lee, Hyunjoo Lee, Se-Ho Kim, Baptiste Gault
Summary: The introduction of interstitial dopants offers a new approach to optimize the catalytic activity of nanoparticles. However, the stability of a property-enhancing dopant (B) introduced in the controlled synthesis of a Pd aerogel electrocatalyst is significantly reduced after the hydrogen oxidation reaction. First-principles calculations suggest that the presence of H on the surface leads to the departure of subsurface B from the Pd nanostructure. This destabilization of subsurface B is more pronounced with increased H occupation of surface and interstitial sites. Thus, H2 fuel itself promotes the microstructural degradation and activity drop of the electrocatalyst.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Physical
Phil Woong Kang, Gui-Min Kim, Robert Haaring, Jae Won Lee, Sun Seo Jeon, Doh C. Lee, Hyunjoo Lee
Summary: The study explores a CO2 electrolyzer utilizing gold nanoparticles grown on silver nanowires to improve energy efficiency by combining electricity and light. The use of plasmonic catalysts shows potential in enhancing electrochemical reduction and increasing energy efficiency in CO2 electrolysis.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Physical
Jihyeon Song, Myeong Gon Jang, Kyung-Jong Noh, Yunkyung Kim, Jeong Woo Han
Summary: We enhanced the reactivity of Pt-loaded TiO2 catalysts for the water-gas shift reaction (WGSR) by inducing TiO2 support to form nanotubes and doping with vanadium. By conducting in situ DRIFTS, XPS, pulsed reaction, and isotopic exchange experiments, we studied the reaction mechanisms and factors contributing to the increased catalytic activity. The Pt-loaded V-doped tube-shaped TiO2 catalyst showed significantly improved WGSR activity, attributed to increased surface area, better dispersion of loaded metal, and H2O dissociation ability. This study highlights the potential of modified Pt-loaded TiO2 catalysts for WGSR process and the synergistic effect of TiO2 shape control and V-doping on catalytic activity, also providing a systematic mechanism study to elucidate the impact of active factors on catalysts.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Woonsuk Yeo, Dongjae Shin, Moon Hyeon Kim, Jeong Woo Han
Summary: Oxidation of elemental Hg (Hg-0) is an efficient method to remove harmful Hg from coal combustion flue gas, and the development of a highly active V2O5/TiO2 catalyst is essential. Density functional theory calculations were used to investigate the effects of support tuning methods on Hg oxidation activity and electronic environment at the active site. Phase control improved activity, while reduction treatment decreased activity due to the change of charge density at V2O5.
Article
Engineering, Electrical & Electronic
Myeong Jin Seol, Seung Hwan Hwang, Jeong Woo Han, Ho Won Jang, Soo Young Kim
Summary: The demand for sensors in various fields has grown, leading to the development of materials that can be attached to the body. Halide perovskite, with its excellent optoelectrical properties, is considered suitable for sensor applications. This study examines the research trends of halide perovskites to develop different types of sensors. While research has been conducted on gas sensors, little has been done on magnetic sensors. The feasibility of implementing five senses sensors is discussed by conducting extensive research on these sensors.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Hyunkyu Oh, Young Jun Lee, Eun Ji Kim, Jinseok Park, Hee-Eun Kim, Hyunsoo Lee, Hyunjoo Lee, Bumjoon J. Kim
Summary: Mesoporous carbon particles have unique structural properties that make them suitable as support materials for catalytic applications. This study investigates the impact of channel nanostructures on the catalytic activity of porous carbon particles (PCPs) by fabricating PCPs with controlled channel exposure on the carbon surface. The results show that PCPs with highly open channel nanostructures exhibit significantly higher catalytic activity compared to those with closed channel nanostructures.
Article
Chemistry, Physical
Selvaraj Seenivasan, Hyeonae Im, Taewaen Lim, Jeong Woo Han, Junhyeok Seo
Summary: This study discovers that a classical Schottky junction electrode can eliminate the non-conductive lamination of poor conductive catalysts, enhancing the activity of water splitting reactions. Specifically, the experiments demonstrate that a Schottky junction electrode formed by a nickel-tungsten nitride alloy and NiFeOOH can achieve high current densities at overpotentials of 11 mV and 181 mV, respectively.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Applied
Seokhyun Choung, Heejae Yang, Jinuk Moon, Wongyu Park, Hyeokjoon June, Chaesung Lim, Jeong Woo Han
Summary: This study investigates how the local coordination of metal in metal-nitrogen doped carbon catalysts affects the activity and selectivity of the chlorine-evolution reaction (CER) by using density functional theory calculations and machine learning approaches. The results show that adjusting the metal's local coordination can effectively tune the CER activity and selectivity of the catalysts. The study also finds that the electronic parameters of the metal and coordination-related features play a significant role in determining the Cl binding tendencies.