Review
Chemistry, Multidisciplinary
Guangbo Chen, Xiaodong Li, Xinliang Feng
Summary: Electrocatalytic splitting of water for hydrogen production is a sustainable and clean technology, but its efficiency is limited by the sluggish oxygen evolution reaction. Coupling electrooxidation of organic compounds with hydrogen evolution reaction has emerged as an alternative route to greatly improve catalytic efficiency and generate valuable organic compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Multidisciplinary
Xi Cheng, Bruna Palma, Heng Zhao, Hongguang Zhang, Jiu Wang, Zhangxin Chen, Jinguang Hu
Summary: Photoreforming of lignocellulosic biomass to produce gas fuels and value-added chemicals is a promising strategy to address the fossil fuels crisis. Although the utilization of lignin via photoreforming is still in the early stages, it has exciting potential. This review summarizes the latest progress in the photoreforming of lignin-derived components and real lignin, providing insights for lignin photocatalytic valorization and introducing analytic methods for characterizing the conversion and distribution of lignin products. The challenges and perspectives of lignin photoreforming are also discussed, aiming to guide the future valorization of biomass into valuable chemicals and fuels through mild photoreforming processes.
Article
Chemistry, Multidisciplinary
Maorui Wang, Chengqian Zhang, Chenggang Ci, Huanfeng Jiang, Pierre. H. Dixneuf, Min Zhang
Summary: Despite the challenges, we have successfully developed a room temperature approach for the direct construction of alpha-hydroxyalkyl cyclic amines through the strategy of electroreductive alpha-hydroxyalkylation. This method offers a broad substrate scope, simplicity in operation, high chemoselectivity, and does not require pressurized H2 gas or transition metal catalysts. The activation of reactants by the zinc ion generated from anode oxidation plays a crucial role in this transformation. This strategy, combined with substrate activation by Lewis acids, is expected to lead to the development of more useful transformations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Guo-Lin Yang, Chi -Tien Hsieh, Yeu-Shiuan Ho, Tung-Chun Kuo, Youngkook Kwon, Qi Lu, Mu-Jeng Cheng
Summary: By coelectrolysis of CO2 with nitrogen compounds, molecules containing C-N bonds can be generated and synthesized on Cu(111). It has been discovered that the first C-N bond formation occurs through the coupling of gaseous CO2 with surface-bound N1 intermediates generated during the reduction of NO3-/NO2- to NH3, rather than through intermediates from CO2 electrochemical reduction (CO2ER) to CO. The reaction follows the Eley-Rideal mechanism and only requires a single active site.
Review
Chemistry, Physical
Tae-Kyung Liu, Gyu Yong Jang, Sungsoon Kim, Kan Zhang, Xiaolin Zheng, Jong Hyeok Park
Summary: Aqueous photoelectrochemical (PEC) cells are a promising technology for converting solar energy into hydrogen, but their efficiency and cost-effectiveness are limited by sluggish oxygen evolution reaction (OER) kinetics and the low economic value of the produced oxygen gas. Organic upgrading PEC reactions, especially alternative OERs, have gained considerable attention for improving efficiency and economic effectiveness. This review provides an overview of PEC reaction fundamentals, cost analysis, recent advances in organic upgrading reactions using different substrates, and discusses the current status, future prospects, and challenges towards industrial applications.
Article
Chemistry, Multidisciplinary
Dieu-Phuong Phan, My Ha Tran, Eun Yeol Lee
Summary: Polymeric materials play a crucial role in modern society, and biomass can be utilized as a renewable carbon source for the production of bio-based plastics. This review summarizes the applications of Metal-Organic Framework (MOF)-based catalysts in the production of renewable bio-plastic-derived materials and highlights the effects of reaction conditions.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Isaac Choi, Michael J. Trenerry, Ken S. Lee, Nicholas King, John F. Berry, Jennifer M. Schomaker
Summary: In this study, an electrochemically tunable method was developed to achieve the divergent formation of cyclic amines or imines by applying different reaction potentials. Detailed experiments and analysis were conducted to provide mechanistic insight and evaluate atom economy. The method enables selective C-H amidation and imidation reactions, yielding sulfonamide motifs for late-stage modifications.
Article
Chemistry, Applied
Wei Deng, Xuepeng Wang, Chun Ho Lam, Zhe Xiong, Hengda Han, Jun Xu, Long Jiang, Sheng Su, Song Hu, Yi Wang, Jun Xiang
Summary: The electrochemical method is a novel option for bio-oil upgrading due to its mild reaction conditions, control convenience, and carbon neutrality. During electrochemical processing of bio-oil, coke is mainly formed from the polymerization of aromatic components, with reaction time and current density having a promoting effect on coke yields.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Zach Medcalf, Kevin D. Moeller
Summary: Anodic olefin coupling reactions generate new bonds and ring skeletons through a net two electron process that reverses the polarity of a known, electron-rich functional group. The second oxidation step is crucial in determining the success of the reaction.
Review
Chemistry, Organic
Dorian Didier
Summary: Formation of C-C bonds has been a challenge for synthetic organic chemists for decades. Organoboron derivatives, as mild and functional-group-tolerant reagents, have the potential to increase the sustainability of coupling reactions. This review summarizes the different approaches developed for C-C bond formation through intramolecular rearrangements of organoborate species.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Multidisciplinary
Zuozhou Ning, Zhicheng Zhang, Qingsong Yan, Naifu Zhou, Linzi Wen, Xichao Peng, Yu Tang, Pengju Feng
Summary: A mild and practical protocol for selectively time-dependent dehydrogenative C-C coupling, as well as tandem coupling-cyclization reaction between indoles or/and other heteroaromatics via electrochemically oxidative process has been demonstrated. The reaction runs under noble catalyst, external oxidant and inert gas free condition, allowing tunable access to a wide variety of synthetically useful symmetrical or nonsymmetrical heteroarene with aggregation-induced emission (AIE), and polycyclic 3-D indole derivatives with aggregation-caused quenching (ACQ) fluorescence properties. Finally, preliminary mechanistic study indicated that tunable generation of indole cation under various electrolysis potential via regulating N-protecting group was the key to achieve cross-coupling between indoles and other heteroaromatics.
SCIENCE CHINA-CHEMISTRY
(2022)
Article
Environmental Sciences
Jiaojiao Liao, Xuan Yang, Yanxing Dou, Baorong Wang, Zhijing Xue, Hui Sun, Yang Yang, Shaoshan An
Summary: Grassland restoration is an effective method to increase soil carbon stocks, with different contributions from plant-derived particulate organic carbon (POC) and microbial-derived mineral-associated organic carbon (MAOC). 30-year grassland restoration increased POC by 47% and MAOC by 41%. POC was mainly influenced by plant biomass, while MAOC was affected by microbial necromass and leaching of calcium-bound carbon. Both POC and MAOC play important roles in soil organic carbon sequestration during grassland restoration.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Chemistry, Multidisciplinary
Huifang Jiang, Rui Lu, Xiaolin Luo, Xiaoqin Si, Jie Xu, Fang Lu
Summary: This study introduces a novel method to transform lignin-derived alcohols into functionalized bibenzyl chemicals, using a molybdenum catalyst for short deoxygenation coupling pathway. The research shows that benzyl carbon-radical is the key intermediate for the formation of bibenzyl products, and the para methoxy and phenolic hydroxyl groups play a role in stabilizing radical intermediates and facilitating selective production of bibenzyl products. The findings provide a promising application for producing functionalized aromatics from biomass-derived materials.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Metallurgy & Metallurgical Engineering
Atul Sharma, Kazuya Uebo, Takahiro Shishido
Summary: In this study, a solvent based chemical upgrading process was used to upgrade biomass. The upgraded biomass showed properties similar to caking coals and the solute fraction in biomass was higher compared to coal. Addition of the upgraded biomass improved fracture strength and bulk density of coal.
ISIJ INTERNATIONAL
(2023)
Article
Chemistry, Multidisciplinary
Francesco Ferlin, Federica Valentini, Assunta Marrocchi, Luigi Vaccaro
Summary: This perspective discusses the development of reductive chemical processes based on low-pressure hydrogen, focusing on the use of alternative liquid organic hydrogen carriers (LOHCs) for diverse biomass-based feedstock. Research has mainly been dedicated to transforming biobased platform molecules and upgrading lignin using H-2 sources.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Chemistry, Physical
Yong Yuan, Raul F. Lobo, Bingjun Xu
Summary: Determining the structure of Ga-containing catalytic sites in Ga/H-ZSM-5 catalyst for propane dehydrogenation (PDH) has been a challenge due to the complexity of the system. In this study, two types of Ga species were differentiated using quantitative pulse titration reactions. The highly active divalent Ga species, identified as Ga2O22+, showed at least 18 times higher PDH activity than isolated Ga+ species. Additionally, only 30% of the observed Al pair sites were able to stabilize Ga2O22+, providing a method to probe the distribution of Al in zeolites.
Article
Chemistry, Multidisciplinary
Haocheng Xiong, Qiwen Sun, Kedang Chen, Yifei Xu, Xiaoxia Chang, Qi Lu, Bingjun Xu
Summary: Researchers have developed a method to determine the standard adsorption enthalpy of CO on Cu surfaces using quantitative surface enhanced infrared absorption spectroscopy. The results show that on dendritic Cu at -0.75 V vs. SHE, the standard adsorption enthalpy, entropy and Gibbs free energy are 1.5 kJ mol(-1), 37.9 J/(mol K), and -9.8 kJ mol(-1), respectively. Comparison between oxide-derived Cu and dendritic Cu suggests the presence of stronger binding sites on OD Cu, which could favor multicarbon products. This work will help establish the correlation between CO binding energy and CO(2)RR activity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Yawei Li, Arnav Malkani, Ramchandra Gawas, Saad Intikhab, Bingjun Xu, Maureen Tang, Joshua Snyder
Summary: We investigate the influence of hydrophobic ionic liquid (IL) thin films on interfacial water structure and its impact on the electrochemical oxygen reduction reaction (ORR). Our findings demonstrate that IL thin films reduce water content at the interface and inhibit the formation of hydrogen bond stabilized water organization. This exclusion of water leads to a decrease in the coverage of OHad spectator species, weakening its interaction with the catalyst surface and lowering the barrier to the last step in the ORR mechanism. Microkinetic modeling confirms the destabilized impact of OHad on ORR kinetics.
Article
Multidisciplinary Sciences
Jing Li, Haocheng Xiong, Xiaozhi Liu, Donghuan Wu, Dong Su, Bingjun Xu, Qi Lu
Summary: The authors demonstrate a Cu-based catalyst with Cu-Ag interfacial sites that promotes the production of oxygenate in CO2 electroreduction, resulting in near 80% selectivity for multi-carbon liquid products. This catalyst exhibits high Faradaic efficiencies for C2+ liquid products in CO electroreduction at commercially relevant current densities, and the performance is retained over 100 hours. The lower affinities of the Cu-Ag interfacial sites for carbon and oxygen are proposed to be responsible for the enhanced selectivity, which is supported by experimental evidence.
NATURE COMMUNICATIONS
(2023)
Review
Chemistry, Multidisciplinary
Yong Yuan, Zhaoqi Zhao, Raul F. Lobo, Bingjun Xu
Summary: This review surveys existing propane dehydrogenation (PDH) catalysts and describes in detail the understanding of metal-exchanged zeolite catalysts. The case of Ga/H-ZSM-5 is used to demonstrate that advances in structure-activity relations often accompany breakthroughs in technology or concepts. In situ/operando characterizations have improved the understanding of Ga speciation under PDH conditions, and the local coordination environment of Ga species on the zeolite support is found to have a decisive impact on the active site structure. Quantitative characterization, determination of intrinsic reaction rates, and computational modeling are all significant in identifying the most active structure in these complex systems. The mechanisms proposed for Ga/H-ZSM-5 in PDH, namely the carbenium mechanism and the alkyl mechanism, may be intricately related or nearly independent of the assumed active structure. Potential approaches to further elucidate the active structure and reaction mechanisms of metal-exchanged zeolite catalysts are discussed in the final section.
Article
Chemistry, Multidisciplinary
Kaiyue Zhao, Yu Tao, Linke Fu, Chen Li, Bingjun Xu
Summary: The presence of BF2(OH)2- anion in the mixed KBi/KF electrolyte enhances the rate of oxygen evolution reaction (OER) at near-neutral pH by stabilizing the interfacial pH and activating the interfacial water. Using the KBi/KF electrolyte, electrodeposited Co(OH)2 achieves a high activity of 100 mA/cm2 at 1.74 V, demonstrating the potential of electrolyte-engineering in improving the electrochemical performance of OER.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Wenqiang Gao, Yifei Xu, Haocheng Xiong, Xiaoxia Chang, Qi Lu, Bingjun Xu
Summary: In this study, the correlation between CO binding energy and Faradaic efficiencies (FE) for C2+ products in the electrochemical CO2 reduction reactions (CO2RR) was experimentally verified for the first time. The relative abundance of Cu sites active for the CO2-to-CO conversion and the further reduction of CO was identified as another key descriptor.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Hao Tian, Yiwei Liu, Bingjun Xu
Summary: In this study, the impact of spatial confinement on the performance and kinetics of boron oxide supported on silica with different pore structures in ODHP was investigated. The results showed that the formation rate of propylene decreased with the degree of confinement of active boron sites derived from the support. Moreover, the observed propane reaction order exhibited a positive correlation with the apparent activation energy. The trend in propane reaction order and apparent activation energy could be rationalized by the rate expression derived based on the proposed radical chain mechanism with three distinct pathways of propane activation.
Article
Chemistry, Physical
Qikai Shen, Hanwen Yang, Kaiyue Zhao, Leyu Liu, Qiwen Sun, Xiaoxia Chang, Hai Xiao, Bingjun Xu
Summary: This study reveals the significant impact of the Fermi level of Pt, Pd, and Rh nanoparticles on the thermocatalytic (hemi)hydrogenation of ethylene and acetylene. Electric polarization through applying a potential bias can tune the rate and product distribution of ethylene hydrogenation and increase the rate and selectivity of acetylene hydrogenation. This research holds promise for advancing both catalyst design and mechanistic understanding in heterogeneous catalysis.
Article
Chemistry, Physical
Kaiyue Zhao, Qikai Shen, Yu Tao, Jieran Li, Maolin Wang, Chen Li, Bingjun Xu
Summary: This study reports an atomically dispersed Co catalyst that efficiently converts olefins to ketones and alcohols under ambient conditions. The reactions proceed through a heterogeneous hydrogen atom transfer mechanism and the oxygen coordination in the Co catalyst enhances the catalytic activity.
Article
Chemistry, Physical
Wenqiang Gao, Yifei Xu, Linke Fu, Xiaoxia Chang, Bingjun Xu
Summary: The electrochemical CO2 reduction reaction on Cu is believed to occur via two consecutive and orthogonal reaction steps, but we provide experimental evidence challenging this assumption. We show that CO2 promotes the electrochemical CO reduction reaction and there are at least two types of Cu sites, with one being more active in CO2-to-CO conversion and the other favoring further reduction to C2+. CO adsorbed on Cu-CO is more active towards C2+ formation compared to Cu-CO2. Isotopic labelling experiments suggest Cu-CO2 and Cu-CO correspond to Cu(111)-like and defect sites, respectively. These insights suggest the possibility of controlling selectivity in the CO2 reduction reaction.
Article
Chemistry, Physical
Haochen Zhang, Chunsong Li, Wenxuan Liu, Guangsheng Luo, William A. A. Goddard III, Mu-Jeng Cheng, Bingjun Xu, Qi Lu
Summary: We report an aqueous reaction system using Cu powder as the catalyst and O-2 as the oxidant, which can selectively convert light alkanes into corresponding olefins and oxygenates at room temperature and ambient pressure. Ethane can be converted to a combination of ethylene and acetic acid with a high rate and selectivity, while propane is converted to propylene and methane mainly produce carbon dioxide, methanol, and acetic acid. Mechanistic understandings propose the activation of the C-H bond by surface oxide species generated during the oxidation process, forming alkyl groups as key intermediates.
Article
Chemistry, Multidisciplinary
Haocheng Xiong, Jing Li, Donghuan Wu, Bingjun Xu, Qi Lu
Summary: This study benchmarked three commercial Cu catalysts in CO2RR using a gas-diffusion type microfluidic flow electrolyzer. The results showed that commercial Cu can achieve a high FE of nearly 80% for C2+ product formations at 300 mA cm(-2). By adjusting the catalyst loading, a high reaction rate of nearly 1 A cm(-2) with a C2+ product FE over 70% was achieved. The study demonstrated that commercial Cu can achieve similar or better performances compared to many current catalysts by design in the CO2RR using similar electrolyzers. Additionally, high CO reduction reaction (CORR) performance can also be achieved on commercial Cu, and the disparities between CO and CO2 electrolysis were discussed.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Kaiyue Zhao, Hao Yu, Haocheng Xiong, Qi Lu, Yi Qin Gao, Bingjun Xu
Summary: This study demonstrates that bulky organic cations can induce a long-range structure of interfacial water molecules and enhance the kinetics of hydrogen oxidation and evolution reactions, even when located outside the outer Helmholtz plane. The structure-making ability of these cations promotes the formation of hydrogen-bonded water chains connecting the electrode surface to the bulk electrolyte, facilitating the reactions. These findings highlight the prospect of utilizing nonlocal mechanisms to improve electrocatalytic performance.
Article
Chemistry, Multidisciplinary
Xiaoxia Chang, Jing Li, Haocheng Xiong, Haochen Zhang, Yifei Xu, Hai Xiao, Qi Lu, Bingjun Xu
Summary: This study experimentally confirms that the rate-determining step in the electrochemical CO reduction reaction on Cu catalysts is the hydrogenation of CO with adsorbed water, rather than the CC coupling reaction. This finding contributes to a better understanding of the mechanism of the CO reduction reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)