Article
Chemistry, Inorganic & Nuclear
Chaoqun Guan, Hao Chen, Hongbin Feng
Summary: Researchers have successfully synthesized a series of Pt/RE nanoalloy catalysts with tunable compositions and ultrasmall particle sizes using a universal chemical method. These nanoalloys exhibit excellent catalytic activity and stability.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Ali Saad, Yang Gao, Kwadwo Asare Owusu, Wei Liu, Yanyan Wu, Aymeric Ramiere, Haichuan Guo, Panagiotis Tsiakaras, Xingke Cai
Summary: Transition metal borides are promising electrocatalysts for water splitting due to their conductivity and durability. In this work, the authors successfully synthesized highly crystalline ternary borides Mo2NiB2, which showed low overpotentials for both the oxygen evolution reaction and hydrogen evolution reaction in alkaline media.
Article
Chemistry, Multidisciplinary
Xiaojian Hou, Yi Song, Yueju Zhao, Wenxiu Li, Zanwu Guo, Shaoru Tang, Yanan Ma, Ruiwen Sun, Qian Wang, Wei Li
Summary: Hierarchically porous carbon (HPC) nanomaterials were successfully synthesized using a heated-evaporation induced self-assembly (HISA) method with a micelle system as the template. The as-prepared HPC showed well-ordered and uniform mesoporous structure, making it suitable for energy storage and conversion applications. The MnO2/HPC composites exhibited outstanding electrochemical activity in supercapacitors with high specific capacitance and excellent cycling performance, demonstrating the potential for mass industrial production in electrochemical applications.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Qiankun Hou, Nan Yang, Kang Liu, De Ding, Yongpeng Lei, Min Liu, Yin Chen
Summary: Atomically dispersed metal catalysts with high metal atom utilization and catalytic activity have been a challenge to design and prepare on a large scale, mainly due to high-temperature pyrolysis. This study presents a two-step solution using a porous metal-organic framework to spatially confine an iron precursor complex and immobilize it on a surface at a relatively low temperature. The resulting catalyst with atomically dispersed iron sites demonstrates tunable and extraordinary catalytic performance in oxygen evolution reactions, attributed to fully exposed iron sites on the surface. The fabrication method provides a facile approach for the rational design of high-performance, stable, and atomically dispersed metal-nitrogen-carbon electrocatalysts with tunable metal content.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Xu Chen, Jinyu Zhao, Jie Lian, Xiaomin Wang
Summary: In this study, a Pt-Ni alloy catalyst with ultrafine size and surface defects was designed and fabricated. Abundant surface defects were created in the catalyst and were considered highly active methanol oxidation catalytic sites. The catalyst exhibited a remarkable performance, with a 6.3-times higher mass activity compared to commercial Pt/C catalyst and retained 79.8% of its initial mass activity after durability measurement. The results showed that the surface defects and modified electronic structure contributed to the enhanced methanol oxidation performance.
Article
Chemistry, Physical
Guanzhi Wang, Wenhuan Cao, Zhe Zhang, Lingyi Liu, Chun Wang, Jie Yin, Huawei Zhou
Summary: This study presents the synthesis of ultrathin ternary sulfide nanoparticles and their excellent catalytic performance and stability in the oxygen evolution reaction.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Jiangnan Guo, Jinlong Liu, Xichen Mao, Shengqi Chu, Xinxin Zhang, Ziyu Luo, Jie Li, Bowen Wang, Chuankun Jia, Dong Qian
Summary: The construction of uniform PtCo nanoparticles grown on N-doped carbon frameworks via pyrolyzing Pt and Co ions adsorbed polyaniline allows for effective tuning of the nanoalloys' structure, resulting in optimal HER performance in 0.5 M H2SO4. Further density functional theory calculations reveal that the improved HER activity on PtCo(111) is originated from the strong electronic interaction between Pt and Co with favorable electron transfer.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Min Zhu, Chao Zhang
Summary: The study develops a novel catalyst based on FeCo alloy nanoparticles encapsulated by pod-like N-doped carbon nanotubes. The optimized catalyst exhibits a half-wave potential close to commercial Pt/C in the oxygen reduction reaction, along with superior stability and methanol tolerance. Moreover, when utilized as a cathode in zinc-air batteries, the catalyst achieves high open-circuit potential, remarkable peak power density, and satisfactory stability.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Chenming Fan, Pukang Wen, Guoqing Li, Guomin Li, Jingjiu Gu, Qingfeng Li, Bing Li
Summary: This study introduces a novel and facile strategy for the chemical synthesis of Pt5La nanoalloys, which show significant improvement in ORR and MOR performances compared to the commercial JM-Pt/C catalyst.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Multidisciplinary
Yasukazu Kobayashi, Shohei Tada, Masaru Kondo, Kakeru Fujiwara, Hiroshi Mizoguchi
Summary: Intermetallic CaPt2 nanoparticles, prepared using a molten salt method, exhibited superior catalytic activity compared to a commercial Pt/C catalyst in the hydrogenation of ketones to alcohols, which could be attributed to electron-rich Pt sites in CaPt2.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Shu-Fang Li, Jie Zheng, Liang Hu, Yao Ma, Dong Yan
Summary: A series of excellent oxygen evolution reaction (OER) perovskite catalysts were obtained by immersing Sr2CoFeO6 in a diluted HNO3 solution. The 24 h etched Sr2CoFeO6 sample (SCFO-24) exhibited the best OER activity, with an overpotential of 300 mV at 10 mA cm(-2) and a Tafel slope of 59.62 mV dec(-1). The improved OER activity of SCFO-24 can be attributed to the enhanced specific surface area derived from selective dissolution of a large amount of Sr and the high ratio of oxidative oxygen species (O2-/O-). Our work promotes this simple but efficient approach to improving the OER performance of perovskite oxides.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Junnan Yao, Yajun Ji, Lijun Pei, Shufen Tan, Fuyong Ren
Summary: In this study, a hierarchical nanocomposite with amorphous FeOOH nanoparticles decorated on defect-rich porous Ni MOF nanosheets was constructed via electrodeposition, showing improved OER performance, enhanced conductivity, and remarkable stability. The synergistic effect between the defect-rich porous Ni MOF and amorphous FeOOH nanoparticles led to higher OER performance, lower Tafel slopes, and smaller charge transfer resistance compared to each individual component as an electrocatalyst.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Hoonkee Park, Jae Wung Bae, Tae Hyung Lee, Ik Jae Park, Changyeon Kim, Mi Gyoung Lee, Sol A. Lee, Jin Wook Yang, Min-Ju Choi, Sung Hyun Hong, Soo Young Kim, Sang Hyun Ahn, Jin Young Kim, Hyoung Seop Kim, Ho Won Jang
Summary: This study introduces medium-entropy alloys (MEAs) as electrocatalysts for oxygen evolution reactions (OERs), which possess high catalytic activity and long-term stability. The surface properties of MEA are tailored to adapt to OER, enabling efficient water splitting cells with sustainable high efficiency.
Article
Chemistry, Physical
Yinlong Zhu, Hassan A. Tahini, Jing Zhou, Yu Chen, Qian Lin, Zhiwei Hu, Rong Fan, Sixuan She, Hong-Ji Lin, Chien-Te Chen, Sean C. Smith, Zongping Shao, Huanting Wang
Summary: The research demonstrates that the A/B-site cosubstitution strategy can optimize the electronic structures of oxygen-deficient brownmillerite oxides to enhance OER catalytic performance. The optimized CaSrCoFeO6-delta (CSCF) exhibits multiple advantageous electronic structure features for OER catalysis, achieving ultrahigh activity outperforming noble metals and other metal oxides.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yamei Wang, Lanli Chen, Huaming Zhang, Muhammad Humayun, Junhong Duan, Xuefei Xu, Yanjun Fu, Mohamed Bououdina, Chundong Wang
Summary: A Ru-doped bimetal oxide catalyst deposited on a conductive nickel foam was fabricated for effective water splitting in alkaline media. The catalyst showed improved catalytic activity, low electrolysis potential, and good stability. The electronic structure regulation in the catalyst optimized the adsorption energy, resulting in increased hydrogen production efficiency.
Article
Mechanics
Jiaxing Song, Zhen-Hua Wan, Nansheng Liu, Xi-Yun Lu, Bamin Khomami
Summary: A high-order transition route has been discovered in Taylor-Couette flows of polymeric solutions, transitioning from inertial to elasticity-dominated turbulence via direct numerical simulations. This two-step transition route involves stabilizing inertial turbulence to laminar flow resembling modulated wavy vortex flow, then destabilizing the laminar flow state to elasticity-dominated turbulence. This transition is achieved by enhancing the extensional viscosity and hoop stresses of the polymeric solution.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Multidisciplinary
Brian Joseph Edwards, Mohammad Hadi Nafar Sefiddashti, Bamin Khomami
Summary: This study tackles the challenge of calculating nonequilibrium entropy in polymeric liquids undergoing flow by extending equilibrium thermodynamics and applying it to nonequilibrium conditions. By introducing internal variables that quantify the internal microstructure of chain-like macromolecules and assuming an evolution of quasi-equilibrium states, the authors were able to determine the nonequilibrium entropy at different levels of coarse-graining.
Article
Mechanics
Brian J. Edwards, M. Hadi Nafar Sefiddashti, Bamin Khomami
Summary: This retrospective covers the growth and application of atomistic simulations of alkanes and polyethylenes over a 50-year period, focusing on the development of accurate potential models and the application of molecular dynamics methodology. The authors summarize the results of simulations from the past 50 years, providing a coherent history of the subject and highlighting the significant impacts on the field of polymer rheology.
JOURNAL OF RHEOLOGY
(2022)
Article
Mechanics
Mandi Boudaghi, M. Hadi Nafar Seddashti, Brian J. Edwards, Bamin Khomami
Summary: Dissipative particle dynamics (DPD) simulations replicate the coil-stretch transition (CST) and configurational relaxation of entangled polyethylene melts observed in planar elongational flow (PEF). The width of the CST hysteresis loop is larger for longer molecule liquids. Reducing the flow Deborah number results in a two-stage relaxation process, with initial stratification followed by configurational relaxation.
JOURNAL OF RHEOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Shiyu Fan, Sobhit Singh, Xianghan Xu, Kiman Park, Yubo Qi, S. W. Cheong, David Vanderbilt, Karin M. Rabe, J. L. Musfeldt
Summary: This study reports the vibrational properties of yttrium-stabilized HfO2 crystals and reveals the characteristic modes of polar orthorhombic hafnia by comparing the Raman and infrared spectra of different crystal phases. This research is of significance for analyzing the high-kappa dielectric and ferroelectric properties in chip technologies.
NPJ QUANTUM MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
K. Park, M. O. Yokosuk, M. Goryca, J. J. Yang, S. A. Crooker, S-W Cheong, K. Haule, D. Vanderbilt, H-S Kim, J. L. Musfeldt
Summary: In this study, by combining magneto-optical spectroscopy and first-principles calculations, we reveal the nonreciprocity and formation mechanism of Ni3TeO6 in the toroidal geometry. Additionally, we demonstrate the deterministic control of nonreciprocal directional dichroism in Ni3TeO6. These findings are of great significance for the development of photonics applications that utilize the unique symmetry characteristics of materials.
NPJ QUANTUM MATERIALS
(2022)
Article
Mechanics
Jiaxing Song, Nansheng Liu, Xi-Yun Lu, Bamin Khomami
Summary: Three-dimensional elastic turbulence in Taylor-Couette flows of dilute polymer solutions has been achieved and studied through direct numerical simulations. A novel flow transition pathway from elastically dominated turbulence to solitary vortex pairs and eventually to purely elastic turbulence is observed by decreasing fluid inertia. The dominant flow features in the elastic turbulence regime are large-scale unsteady vortex pairs and small-scale traveling waves. Furthermore, the study concludes that the production of turbulent kinetic energy in purely elastic turbulence is solely due to the stochastic nature of polymer stretch/relaxation.
JOURNAL OF FLUID MECHANICS
(2022)
Review
Multidisciplinary Sciences
Jiaxing Song, Yabiao Zhu, Fenghui Lin, Nansheng Liu, Bamin Khomami
Summary: This retrospective aims to present a coherent history of important findings in direct numerical simulations and experiments in turbulent Taylor-Couette flow of dilute polymeric solutions in the last decade. Specifically, the article discusses the sequence of flow transitions due to an increase in fluid elasticity, including drag modification, flow structures, statistics, and mechanisms of turbulence, as well as a comparison with curvilinear and rectilinear shear flows. This article is part of a theme issue on Taylor-Couette and related flows.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Chemistry, Physical
Mahdi Boudaghi, Brian J. J. Edwards, Bamin Khomami
Summary: The evolution of shear banding under startup of shear flow was simulated for different molecular weight polyethylene melts. It was found that shear stress was dominated by segmental orientation at low shear rates, but flow-induced disentanglement resulted in the onset of chain tumbling and reduced shear stress at a critical shear rate. During shear flow startup, distinct fast and slow bands formed, consisting of more disentangled and extended chains and relatively entangled and coiled molecules, respectively. The simulation results showed temporary reverse flow, consistent with earlier experiments and theoretical results. The phenomenon of shear banding appeared to arise from flow-induced disentanglement and differential stretching of individual chains, resulting in the formation of slow and fast bands.
Article
Physics, Fluids & Plasmas
Jiaxing Song, Fenghui Lin, Yabiao Zhu, Zhen-Hua Wan, Nansheng Liu, Xi-Yun Lu, Bamin Khomami
Summary: Direct numerical simulation is used to identify the dominant flow structures in the Taylor-Couette flow of dilute polymer solutions. It is found that unsteady diwhirls and elastic waves play important roles in the formation of elastic turbulence. The interaction between these elements leads to stochastic or chaotic cycles that sustain the turbulent dynamics.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Mechanics
Yabiao Zhu, Zhenhua Wan, Fenghui Lin, Nansheng Liu, Xiyun Lu, Bamin Khomami
Summary: The existence of a maximum drag enhancement (MDE) asymptote at high rotation (Ro) and Weissenberg (Wi) numbers in turbulent viscoelastic spanwise-rotating plane Couette flow has been demonstrated. Above a critical Wi, drag enhancement plateaus and the MDE asymptote is realized in a broad range of Ro. The mean velocity profiles at MDE closely follow a log-law profile that has a nearly identical slope but different intercepts as a function of Ro. Moreover, the intriguing finding is that MDE occurs in the elasto-inertial turbulence (EIT) flow state and is mainly sustained by elastic forces like the MDR flow state. Hence, a universal picture of elastically induced drag modification asymptotes is emerging, where these asymptotic states are inherent to the elastically sustained EIT flow state.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Polymer Science
Mohammad Hadi Nafar Sefiddashti, Brian J. Edwards, Bamin Khomami
Summary: Atomistic simulations were performed on linear, entangled polyethylene melt under uniaxial elongational flow conditions. Flow-induced phase separation and crystallization were observed at intermediate and high flow strengths, respectively. The flow-induced crystallization occurred at a temperature higher than the quiescent melting point and remained stable after flow cessation. The results were consistent with experimental measurements of thermodynamic properties.
Article
Chemistry, Multidisciplinary
Mahshid Mokhtarnejad, Erick L. Ribeiro, Dibyendu Mukherjee, Bamin Khomami
Summary: In this study, hybrid nanocomposites (HNCs) based on manganese oxides (MnOx/Mn3O4) and reduced graphene oxide (rGO) were synthesized as active electrodes for energy storage devices. The active material was composed of MnOx/Mn3O4 nanorods and nanoparticles embedded in rGO nanosheets. The performance of the active layer was highly correlated with the MnOx/Mn3O4 to rGO ratio and the morphology of MnOx/Mn3O4 nanostructures in HNCs. Electrochemical characterizations showed that the MnOx/Mn3O4-rGO composite exhibited significantly higher specific capacitance compared to commercially available Mn3O4-graphene nanocomposites. The study has paved the way for the use of LASiS-based synthesized functional material in combination with additive manufacturing techniques for all-printed electronics with superior performance.
Article
Materials Science, Multidisciplinary
K. Park, G. L. Pascut, G. Khanal, M. O. Yokosuk, Xianghan Xu, Bin Gao, M. J. Gutmann, A. P. Litvinchuk, V Kiryukhin, S-W Cheong, D. Vanderbilt, K. Haule, J. L. Musfeldt
Summary: By combining optical spectroscopy and electronic structure calculations, we revealed the charge gap in the polar magnet Fe2Mo3O8 and discussed the structure-property relationships in metal-substituted systems such as Ni, Mn, Co, Zn.
Article
Chemistry, Physical
Erick L. Ribeiro, Elijah M. Davis, Mahshid Mokhtarnejad, Sheng Hu, Dibyendu Mukherjee, Bamin Khomami
Summary: This study presents a facile technique for synthesizing Pt-Co bimetallic nanoparticles with superior electrocatalytic activities for oxygen reduction reaction. By adjusting the precursor concentrations, a higher degree of Pt-Co alloying can be facilitated to enhance catalytic activities while maintaining long-term stabilities in highly concentrated alkaline media. The unique configurations of the Pt-Co nanoparticles coated with a graphitic shell and supported by Co3O4-decorated carbon matrix contribute to the outstanding performances.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Physical
Zi-Ye Liu, Qian-Yu Wang, Ji-Ming Hu
Summary: In this study, a layered carbon dot composite catalyst (NiFe LDH@CDs) was prepared using a one-step coprecipitation method, without the need for heating or hydrothermal treatment. The CD-functionalized catalyst facilitated rapid charge transfer and accelerated the oxygen evolution reaction. Additionally, the heterojunction structure formed between NiFe LDH and CDs efficiently suppressed photoelectron-hole recombination.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
Rohit Kumar, Ankit Kumar Srivastava, Palaniyappan Nagarasu, Vedichi Madhu, Ekambaram Balaraman
Summary: We designed and synthesized a NN-CoII bidentate complex and used it for the amination of alcohols under mild and solventless conditions. The complex exhibited good reactivity towards both primary and sterically hindered secondary alcohols, providing high yields of amines. The pyrazole moiety in the ligand played a crucial role in the reaction. Furthermore, we demonstrated the reusability of the complex as a homogeneous cobalt catalyst.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
Shivanand Chettri, Liang-Ting Wu, Sagarmani Rasaily, Debesh Sharma, Bikram Gurung, Rajani Dewan, Sudarsan Tamang, Jyh-Chiang Jiang, Anand Pariyar
Summary: Replicating the enzymatic surface microenvironment in vitro is challenging, but constructing an analogous model could facilitate our understanding of surface effects and aid in developing an efficient bioinspired catalytic system. In this study, five unique Cu2O morphologies were generated, and the surface morphology variations were found to be a consequence of differences in the exposure of low-index facets. The reactivity of Cu2O was found to be influenced by the proportion of {110} planes, with r-Cu2O exhibiting the highest reactivity.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
Yong Tang, Jianhao Qiu, Dingliang Dai, Guanglu Xia, Lu Zhang, Jianfeng Yao
Summary: Defect engineering has been shown to improve the photocatalytic performance. This study investigated the use of defect-rich UiO-66-NH2 wrapped by ZnIn2S4 as a catalyst for photocatalytic H2O2 production. The defects in UiO-66-NH2 enhanced O-2 adsorption and charge separation, leading to higher H2O2 yield. The insights from this work can advance the research in defect engineering of MOFs and photocatalytic H2O2 synthesis.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
Ruiyang Qu, Shuxin Mao, Jana Weiss, Vita A. Kondratenko, Evgenii V. Kondratenko, Stephan Bartling, Haifeng Qi, Annette-Enrica Surkus, Kathrin Junge, Matthias Beller
Summary: The hydrogenation of amides, a challenging reaction usually performed at high temperatures, has been achieved under milder conditions using a new Pt-MoOx/TiO2 catalyst. This catalyst system enables the selective hydrogenation of various amides and imides.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
Xiaoran Niu, Ao Wang, Lei Tong, Lei Wang, Yuan Kong, Chenliang Su, Hai-Wei Liang
Summary: This study introduces a novel intermetallic PdCu3 catalyst supported on defective nanodiamond-graphene (ND@G), which exhibits high selectivity (95%) and remarkable activity (turnover frequency: 2940 h(-1)), six times higher than that of the commercial Lindlar catalyst.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Review
Chemistry, Physical
Zhiyuan Zheng, Yiming Yue, Hongying Zhuo, Qinggang Liu, Yanqiang Huang
Summary: This review presents the recent research advances on single-atom catalysis for deep reduction of CO2. Detailed introductions and summaries were classified into three categories based on proton-coupled multi-electron transfer approaches: strengthening metal-support interaction, rational design and regulation of coordination environment, and development of SACs with multi-atom active sites. The challenges and future research directions in the field of SACs for CO2 reduction are also proposed.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
Shiv Kumar, Paramita Datta, Anup Bhunia, Swadhin K. Mandal
Summary: This article reports a transition-metal-free process for in situ denitrogenation of tosylhydrazones, resulting in the production of various sulfones. The authors used a phenalenyl-based odd alternant hydrocarbon as a photoredox catalyst, which acted as a potent oxidant to facilitate the denitrogenation reaction. The method showed wide functional-group tolerance and high yields, making it suitable for late-stage modification of natural products.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)
Article
Chemistry, Physical
L. A. Luque-Alvarez, J. Gonzalez-Arias, F. Romero-Sarria, T. R. Reina, L. F. Bobadilla, J. A. Odriozola
Summary: Currently, the production of acetic acid through the carbonylation reaction of methanol has limitations, leading to the exploration of alternative methods using heterogeneous catalysts. This study investigates the methanol carbonylation reaction over a Cu-H-MOR catalyst and proposes a reaction mechanism based on the catalytic behavior and performance of the catalyst. The results provide insights into the reaction mechanism and the involvement of acid and redox centers.
CATALYSIS SCIENCE & TECHNOLOGY
(2024)