Category Archives: Chemistry

Researchers Develop Dynamic Trimer Catalyst for Efficient Hydrogenations (Chemistry)

A team led by Prof. LU Junling and Prof. WEI Shiqiang from University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) developed a dynamic trimer catalyst for highly efficient hydrogenations by synergizing metal-support interactions and spatial confinement. This catalyst showed good activity, selectivity and stability in selective hydrogenation of acetylene and 1,3 butadiene in olefin rich atmosphere. The study was published in Nature Nanotechnology.

Supported atomic dispersion catalysts (SADCs) have attracted extensive attention due to their high atomic utilization efficiency and unique catalytic performance. Compared with those of traditional metal nanoparticle catalysts, the active sites of SADCs are isolated from each other. They have uniform structures, which makes these catalysts show high selectivity and good anti-carbon deposition performance in hydrocarbon selective hydrogenation.

However, due to the rapid increase in surface free energy, it is a great challenge to obtain catalysts with high loading and high stability under reaction conditions. Among the two standard methods, strong metal-support interactions (MSIs) may lead to a significant reduction in reaction activity, while microporous confined active metals may affect the mass transfer of the reaction. Therefore, the rational design of high loading, high stability and high activity SADCs is in urgent.

The research team led by Prof. LU prepared high loading Ni1Cu2 trimer catalyst on g-C3N4 support, utilizing the strong metal-support interaction between Cu, Ni and rich nitrogen on g-C3N4 support, as well as the confinement of pre-deposited Cu to Ni atoms. The loading of Ni and Cu were 3.1 wt.% and 8.1 wt.% respectively.

In the selective hydrogenation of acetylene in ethylene rich atmosphere, the prepared Ni1Cu2 trimer structure catalyst showed excellent catalytic performance in activity, selectivity and stability. The catalyst realized the complete conversion of acetylene at about 170 ℃, maintains 90% ethylene selectivity, and can maintain stability for more than 350 hours.

The excellent carbon deposition resistance of the above catalyst was further proved by in situ synchrotron radiation technology. Prof. WEI revealed the coordination structure information of Ni in hydrogen and acetylene hydrogenation atmosphere with the help of in-situ X-ray absorption spectroscopy (XAFS).

In-situ synchrotron radiation vacuum ultraviolet photoionization mass spectrometry and in-situ thermogravimetry showed that there was no carbon deposition in the reaction process. These characterizations indicated that the possible structure of the catalyst is Cu-OH-Ni-OH-Cu. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DIRTFS) of acetylene hydrogenation reaction showed that OH groups were directly involved in the catalytic reaction.

Furthermore, a team led by Prof. LI Weixue from Dalian Institute of Chemical Physics of CAS determined the spatial configuration of Cu-OH-Ni-OH-Cu structure through theoretical calculation. They revealed that the covalent bond interaction between the three atoms of Ni1Cu2 and the support, and the confinement of Cu atoms on both sides to the intermediate active Ni atom, are the internal reasons for the high stability of the catalyst, and the isolated active Ni site limits the co-adsorption of acetylene and ethylene, making it have excellent carbon deposition resistance.

The coordination of metal-support interaction and atomic confinement brings new insights into dynamic structural changes in the catalytic process, which can not only improve the adsorption of reaction molecules and catalytic activity, but also maintain high stability. The single Ni site makes the catalyst show high selectivity and high carbon deposition resistance.

Featured image: Structural characterization: A representative HAADF-STEM image of Ni1Cu2/g-C3N4 with atomic resolution, where isolated atoms, triangular trimers and linear trimers are highlighted by dashed yellow circles, red triangles and green rectangles, respectively. © Authors


Reference: Gu, J., Jian, M., Huang, L. et al. Synergizing metal–support interactions and spatial confinement boosts dynamics of atomic nickel for hydrogenations. Nat. Nanotechnol. (2021). https://doi.org/10.1038/s41565-021-00951-y


Provided by Chinese Academy of Sciences

Researchers Determine Active Sites of Cu-ZnO Catalysts for Water Gas Shift and CO Hydrogenation Reactions (Chemistry)

The research team led by Prof. HUANG Weixin and Assoc. Prof. ZHANG Wenhua from University of Science and Technology of China of the Chinese Academy of Sciences, collaborating with Prof. WANG Ye from Xiamen University, investigated on the water gas shift (WGS) and CO hydrogenation reactions.

They observed the in situ reconstruction of the catalyst dependent on Cu structure and reaction atmosphere, and determined that CuCu(100) – hydroxylated ZnO interface and CuCu (611)Zn alloy were the active sites of Cu-ZnO catalyst for WGS reaction and CO hydrogenation to methanol reaction, respectively. This study was published in Nature Communications.

Since the introduction of the concept of “active site”, identifying the active site structure of the catalyst has become the “Holy Grail” in the heterogeneous catalytic reaction. This kind of active site structure depends on the catalyzed chemical reaction.

Cu-ZnO-Al2O3 catalyst is widely used in commercial water gas shift (WGS, CO + H2O → CO2 + H2) and CO hydrogenation to methanol (CO + 2H2 → CH3OH), however, the catalytic active site structures of Cu-ZnO-Al2O3 catalyst in these two actions remain unclear.

In this study, the researchers prepared the well-structured ZnO / Cu catalyst via morphology maintaining reduction method based on the well-structured ZnO / Cu2O, and systematically studied the catalytic behavior of ZnO / Cu catalyst in WGS and CO hydrogenation to methanol with the help of in situ characterization technology and theoretical calculation. They found that in the water gas change reaction, ZnO/c-CuCu(100) catalyst showed the highest catalytic activity, and its catalytic performance was positively correlated with the number of Cu(I)CuCu(100)-ZnO interface sites.

Besides, the researchers observed the in situ formation of CuZn alloy in the reaction of CO hydrogenation to methanol. The formation of CuZn alloy was positively correlated with the number of surface defect sites of Cu, and it was formed most easily at the surface defect site of c- CuCu(100) (Cu (611)). The methanol formation rate catalyzed by ZnO / CuCu(100) catalyst is positively correlated with the number of CuZn alloy sites. Combining these results with theoretical calculation, the researchers determined that CuCu (611)Zn alloy is the catalytic active site.

Prof. HUANG has proposed the concept of “nanocrystalline model catalyst“, and carried out researches on catalytic surface chemistry and determined catalyst active sites and catalytic mechanism under industrial catalytic reaction conditions. In former works, his group has studied the structured Cu2O / Cu nanocrystals, and a series of results were published on Angewandte Chemie(in 20112014, and 2019)  and Nature Communications. 

Featured image: a Catalytic performance of representative ZnO/Cu and commercial Cu/ZnO/Al2O3 WGS catalysts for the WGS reaction; b Apparent activation energies (Ea) of various catalysts as a function of ZnO loadings. © Authors


Reference: Zhang, Z., Chen, X., Kang, J. et al. The active sites of Cu–ZnO catalysts for water gas shift and CO hydrogenation reactions. Nat Commun 12, 4331 (2021). https://doi.org/10.1038/s41467-021-24621-8


Provided by Chinese Academy of Sciences

Capacitive Deionization Helps to Remove Tetracycline and Water Hardness Ions Simultaneously (Chemistry)

Tetracycline (TC) is one of the most common broad-spectrum antibiotics. However, typically less than 30% of the antibiotic dose was absorbed by human and animal, while the remainder released into the environment through urine. The coexistence of TC and water hardness ions (Ca2+ and Mg2+) in natural water is a widespread pollution phenomenon. Especially, TC and water hardness ions could easily form TC-metal complex pollution in the environment.In a recent study published in Journal of Cleaner Production, the researchers at Institute of Solid State Physics, Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences used capacitive deionization (CDI) technology to simultaneously remove TC and water hardness ions (Ca2+ and Mg2+) from water based on unique innate advantages of CDI technology. The method is efficient and eco-friendly with low-cost.The researchers derived hierarchical porous carbon material from kelp and used it as symmetric electrodes. A maximum capacity of 925.3 mg g-1 for TC removal was achieved, which is much higher than those of other materials reported. The removal efficiency can achieve over 90% even after five CDI adsorption-desorption cycles.Besides, the metal ions with opposite charges were adsorbed on the counter electrode with a preferential ion electrosorption performances, proving the effective CDI technology for water purification.

This study has paved a way to synchronously eliminate multiple organic and inorganic contaminants from water by using CDI technology.

Featured image: Graphical abstract by authors


Reference: Na Sun, Hongjian Zhou, Haimin Zhang, Yunxia Zhang, Huijun Zhao, Guozhong Wang, Synchronous removal of tetracycline and water hardness ions by capacitive deionization, Journal of Cleaner Production, Volume 316, 2021, 128251, ISSN 0959-6526, https://doi.org/10.1016/j.jclepro.2021.128251. (https://www.sciencedirect.com/science/article/pii/S0959652621024677)


Provided by Chinese Academy of Sciences

How Chemical Reactions Compute? (Chemistry)

A single molecule contains a wealth of information. It includes not only the number of each kind of constituent atom, but also how they’re arranged and how they attach to each other. And during chemical reactions, that information determines the outcome and becomes transformed. Molecules collide, break apart, reassemble, and rebuild in predictable ways. 

There’s another way of looking at a chemical reaction, says SFI External Professor Juan-Pérez Mercader, who is a physicist and astrobiologist based at Harvard University. It’s a kind of computation. A computing device is one that takes information as its input, then mechanically transforms that information and produces some output with a functional purpose. The input and output can be almost anything: Numbers, letters, objects, images, symbols, or something else.

Or, says Pérez-Mercader, molecules. When molecules react, they’re following the same steps that describe computation: Input, transformation, output. “It’s a computation that controls when certain events take place,” says Pérez-Mercader, “but at the nanometer scale, or shorter.” 

Molecules may be small, but their potential as tools of computation is enormous. “This is a very powerful computing tool that needs to be harnessed,” he says, noting that a single mole of a substance has 10^23 elementary chemical processors capable of computation. For the last few years, Pérez-Mercader has been developing a new field he calls “native chemical computation.” It’s a multifaceted quest: He wants to not only exploit chemical computing but also find challenges for which it’s best-suited.

“If we have such a huge power, what kinds of problems can we tackle?” he asks. They’re not the same as those that might be better solved with a supercomputer, he says. “So what are they good for?” 

He has some ideas. Chemical reactions, he says, are very good at building things. So in 2017, his group “programmed” chemical reactions to use a bunch of molecules to assemble a container. The experiment demonstrated that these molecules, in a sense, could recognize information — and transform it in a specific way, analogous to computation. 

Pérez-Mercader and his chief collaborator on the project, chemical engineer Marta Dueñas-Díez at Harvard and the Repsol Technology Lab in Madrid, recently published a review of their progress on chemical computation. In it, they describe how chemical reactions can be used, in a lab, to build a wide range of familiar computing systems, from simple logic gates to Turing Machines. Their findings, says Pérez-Mercader, suggest that if chemical reactions can be “programmed” like other types of computing machines, they might be exploited for applications in many areas, including intelligent drug delivery, neural networks, or even artificial cells. 

Read the review, “Native Chemical Computation. A Generic Application of Oscillating Chemistry Illustrated With the Belousov-Zhabotinsky Reaction,” in Frontiers in Chemistry (May 11, 2021)

Read a related paper, with an example of a consequential chemical computation, in Advanced Materials (2017)

Watch Pérez-Mercader’s related presentation, “Mimicking Life Without Biochemistry” 

Featured image: Polymer vesicles from Perez-Mercader’s chemical computation experiment in 2017. (Anders Albertsen, Jan Szymański & Juan Pérez-Mercader, Nature, 2017)


Reference: Marta Dueñas-Díez et al, Native Chemical Computation. A Generic Application of Oscillating Chemistry Illustrated With the Belousov-Zhabotinsky Reaction. A Review, Frontiers in Chemistry (2021). DOI: 10.3389/fchem.2021.611120


Provided by SantaFe Institute

Researchers Discovered Molecular Dance That Could Eliminate Soot Pollution (Chemistry)

A hidden molecular dance has been revealed that could hold the answer to the problem of soot pollution.

Soot pollution invades our bodies, causing cancer and blood clots as well as weakening us to respiratory viruses. Our atmosphere and glaciers are also blanketed by soot, leading to global heating and increased ice loss. Surprisingly, the way that soot particles form is still unknown but is of pressing concern to solve these global problems.

The reason for this long-running mystery is due to the extreme environment in which soot forms, the rapid speed of the reactions and the complex collection of molecules present in the flame. All of these obscure the pathway to soot formation.

An international team from the UK, Singapore, Switzerland and Italy has used two different microscopes to reveal the molecules and reactions taking place in a flame.

The first microscope operates by touch, feeling for the arrangement of atoms in the molecules of soot. These tactile maps provide the first picture of soot’s molecular chicken wire shape. Quantum chemistry was then used to show that one of the molecules was a reactive diradical. A diradical is a type of molecule with two reactive sites, allowing it to undergo a succession of chain reactions.

The second microscope is entirely virtual and shows the reaction between the diradicals. Quantum mechanics guided a supercomputer to virtually and realistically collide the molecules together and reveal the molecular dance in slow motion.

This simulation showed that the individual molecules are held together by intermolecular forces after they collide. This gives the reactive sites time to find each other and create a permanent chemical bond. Even after they have bonded they remain reactive, allowing more molecules to “stick” to what is now a rapidly growing soot particle.

This discovery could resolve the problems with previous attempts to explain soot formation via either a physical condensation or chemical reaction. In fact, both are required to adequately explain the rapid and high-temperature reactions.

One of the paper’s lead authors, Jacob Martin, commented, “If the concentration of these species is high enough in flames, this pathway could provide an explanation for the rapid formation of soot.”

Co-author Markus Kraft, from the University of Cambridge’s Department of Chemical Engineering and Biotechnology, said, “The project brought together cutting-edge computational modelling and experiments to reveal a completely new reaction pathway which potentially explains how soot is formed. Scientists and engineers have been working on solving this important problem for decades.”

The researchers hope to target these reactive sites to see whether the soot formation process can be halted in its tracks. One promising option is the injection of ozone into a flame, which has already been found to effectively eliminate soot in some preliminary results in other work.

“Diradical aromatic soot precursors in flames” (DOI: 10.1021/jacs.1c05030) is published in Journal of the American Chemical Society by researchers from Cambridge Centre for Advanced Research and Education in Singapore Ltd, University of Cambridge, IBM Research Zurich, Consiglio Nazionale delle Ricerche and Università degli Studi di Napoli Federico II. 

This research is supported by the National Research Foundation, Prime Minister’s Office, Singapore under its Campus for Research Excellence and Technological Enterprise (CREATE) programme.


Provided by Cambridge Cares

Researchers Developed A New Catalyst For Converting Ethanol Into C3+ Olefins (Chemistry)

Oak Ridge National Laboratory researchers have developed a new catalyst for converting ethanol into C3+ olefins – the chemical building blocks for renewable jet fuel and diesel – that pushes the amount  produced to a record-high 88%, a more than 10% gain over their previously developed catalyst.

Increasing the yield from this conversion can advance cost-effective production of renewable transportation fuels.

In the search for new catalysts, ORNL’s Zhenglong Li achieved the record yield by exploring a new reaction pathway using a metal mix of copper, zinc and yttrium. His experiments add to fundamental understanding of how various metals behave in complex chemical reactions while also indicating potential for developing new catalysts and reducing carbon deposits that decrease yield in the catalysis process.

The new research builds on previous work with a conversion process now licensed to Prometheus Fuels and more recent research using a zinc-yttrium beta catalyst combined with a single-atom alloy catalyst.

Featured image: An ORNL research team is investigating new catalysts for ethanol conversion that could advance the cost-effective production of renewable transportation. Credit: Unsplash


This science news has been confirmed by us from ORNL


Provided by ORNL

Oxygen-vacancy-mediated Catalysis Boosts Direct Methanation of Biomass (Chemistry)

Biomethane (CH4) can be used as feedstock for modern chemical industry or burned directly as a fuel.

Currently, CH4 is mainly produced via a multi-step process in which biomass is first gasified into biogas, followed by the methanation of the latter. This method requires high temperature and pressure and shows low selectivity for chemical or biological processes.

Recently, a research group led by Prof. WANG Feng from the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences, in collaboration with Prof. WANG Min’s group from Dalian University of Technology, proposed interfacial oxygen-vacancy (Vo)-mediated catalysis over Ru/TiO2 for the direct methanation of lignocellulosic biomass at temperatures below 200°C and with a selectivity above 95%.

The results were published in Joule on July 27.

“We proposed the Vo-mediated catalysis process to couple the oxidation of biomass into CO2 with the hydrogenation of CO2 into CH4, leading to the direct methanation of biomass under mild conditions,” said Prof. WANG Min.

The researchers found that the biomass substrate molecule was oxidized by the lattice oxygen of Ru/P25 into CO2, and Vo formed on Ru/P25. Subsequently, the dissociated oxygen atoms derived from CO2 could restore the Vo during the CO2 hydrogenation process.

Moreover, they found that the Vo-mediated catalysis process could stably catalyze the production of CH4 from aqueous glycerol at temperatures as low as 120 °C and with a selectivity above 99%.

“This direct methanation process is simpler and more efficient than the traditional two-step process of biogas production and methanation,” said Prof. WANG Feng. “It opens up a new route for the utilization of biomass resources.”

This work was supported by the National Natural Science Foundation of China, the Ministry of Science and Technology of the People’s Republic of China, and the Strategic Priority Research Program of the Chinese Academy of Sciences.

Featured image: Graphical abstract © Zhou et al.


Reference: Hongru Zhou, “Oxygen-vacancy-mediated catalytic methanation of lignocellulose at temperatures below 200°C”, Joule, 2021. DOI: https://doi.org/10.1016/j.joule.2021.07.001


Provided by Chinese Academy of Sciences

Researchers Construct Lab-made ‘Cells’ with Organelles to Mimic Cellular Signaling (Chemistry)

Cells are compartmentalized microreactors that integrate spatially organized organelles in a confined space to afford biochemical reaction networks.

Hierarchical lab-made ‘cells’ with compartmentalized organelles can serve as a model of cellular organization for the study of metabolic reaction network and the design of biological computation.

In a study published in Science Advances, the research group led by Prof. QIAO Yan at the Institute of Chemistry of the Chinese Academy of Sciences, and Prof. LIN Yiyang at Beijing University of Chemical Technology, developed a complex protocell model made of proteins and stuffed with tiny liquid coacervate droplets resembling cellular substructures can respond to changes in their environment, similar to living cells.

This light and pH-sensitive microdroplets are prototype of membraneless organelles formed by short, light-sensitive molecules and long, pH-sensitive polymers via liquid-liquid phase separation. The tiered protocells are capable of harvesting biomacromolecules (e.g., DNA and proteins) by condensing them into liquid droplets, and recruiting small molecules from surroundings, which allows for active control of enzyme-catalyzed reactions.

These subcompartments of protocells can sense a variety of extracellular signals (e.g., light, pH and chemical species), take actions and adapt their physicochemical behaviours, which can be utilized to design Boolean logic gates (NOR and NAND) using biochemical signals as inputs.

The information-processing ability could allow researchers to program the protocells as if they were computer chips, to control chemical reactions.

This study was highlighted in Nature.

Featured image: AzoGlu2/DEAE-dextran coacervate microdroplets. (A) Schematic of active AzoGlu2/DEAE-dextran complexation to produce microdroplet condensation via LLPS. The process is responsive to wavelength-dependent light irradiation, or subtle pH changes triggered disassembly-assembly of coacervates. (B) Phase diagram showing the presence of microdroplets (orange region) at different trans-AzoGlu2/DEAE-dextran molar ratio and trans-AzoGlu2 concentrations. (C) Optical microscopy image and (D) 3D confocal fluorescence microscopy image (loaded with HPTS) showing the formation of coacervate microdroplets in a mixture of trans-AzoGlu2 (10 mM) and DEAE-dextran (10 mM monomer). (E) Optical microscopy image showing disassembly of microdroplets after UV light irradiation for 7 min. (F) Count number of coacervates in the mixture of trans-AzoGlu2 (10 mM) and DEAE-dextran (10 mM monomer) as detected by flow cytometry with different durations of UV light irradiation. Error bars represent the SDs of three independent measurements. (G) Reversible diameter changes of trans-AzoGlu2/DEAE-dextran microdroplets with UV/blue light irradiation for 10 cycles. (H) Transmittance of trans-AzoGlu2/DEAE-dextran mixtures and (I) their coacervate counts suggesting the existence of coacervate microdroplets at a narrow pH window. Scale bars, 10 μm. Credit: DOI: 10.1126/sciadv.abf9000


Reference: Wenjing Mu et al, Membrane-confined liquid-liquid phase separation toward artificial organelles, Science Advances (2021). DOI: 10.1126/sciadv.abf9000


Provided by Chinese Academy of Sciences

Researchers Reveal Molecular Mechanism of Ruthenium Complex Induced DNA Phase Separation (Chemistry)

The phenomenon of “liquid-liquid” phase separation (LLPS) of biological macromolecules in living cells regulates many cell activities.

DNA LLPS manipulates many important processes such as gene transcription, translation, and chromosome high-level structure assembly. Abnormity of DNA LLPS causes oncogene expression, genome inactivation, uncontrolled transcription activation and other cellular processes, which are directly related to fatal diseases.

Recently, a research group led by Prof. LI Guohui from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. MAO Zongwan’s group from Sun Yat-Sen University, revealed the molecular mechanism of ruthenium complex induced DNA phase separation in living cells.

This study was published in Journal of the American Chemical Society on July 22.

Prof. MAO’ group proposed a metal ruthenium complex with high DNA affinity and photo-switching properties to fulfill the real-time detecting and monitoring of DNA phase separation process in living cells. In addition, the metal ruthenium complexes also exhibited potent anticancer activity both in Vitro and in Vivo conditions.

Prof LI’s group utilized multi-scale molecular dynamics simulations to unveil the underlying mechanism of ruthenium complex induced DNA phase separation, where the positively charged lipophilic triphenylphosphine substituents and the flexible long alkyl chains of the ruthenium complex provided significant contributions in inducing DNA assembly.

This study provides new ideas for the design of interventional reagents for inducing DNA phase separation of living cells.

The research was supported by the National Natural Science Foundation of China.

Featured image: Illustration of the mechanisms of DNA phase separation induced by ruthenium complex (Image by ZHANG Yuebin and LI Guohui) 


Reference: Wen-Jin Wang et al, Induction and Monitoring of DNA Phase Separation in Living Cells by a Light-Switching Ruthenium Complex, Journal of the American Chemical Society (2021). DOI: 10.1021/jacs.1c01424


Provided by Chinese Academy of Sciences