Synthesizing Polymers Using CO2

Ring-opening polymerizations produce commercial polymeric materials including epoxy resins, but they usually liberate small molecules such as the greenhouse gas, CO2. In the context of climate change, it is urgent to reduce CO2 emissions. Recently, a group of UK researchers led by Prof. Charlotte K. Williams at the University of Oxford developed a step-growth polymerization method that self-consumed CO2. The work has been published in a recent issue of Chemical Communications.

The synthesis involved two catalytic cycles (Figure 1). The first cycle polymerized L-lactide-O-carboxyanhydride into poly(L-lactide acid) (PLLA) via a ring-opening polymerization and released one CO2 molecule per polymer repeat unit. In the second cycle, epoxide molecules (cyclohexeneoxide) combined with the CO2 generated in the first step and grew into poly(cyclohexene carbonate) (PCHC) from the terminal ends of the PLLA chains. A di-zinc-alkoxide compound catalyzed both cycles and coupled the two processes together. The product is PLLA-b-PCHC block copolymers, which are composed of PLLA and PCHC covalently tethered together.

Figure 1. The two catalytic cycles are joined by a zinc-based catalyst, [LZn2(OAc)2]. The CO2 gas produced in the first step serves as a reactant in the second step. OCA: O-carboxyanhydride; ROP: ring-opening polymerization; CHO: cyclohexeneoxide; ROCOP: ring-opening copolymerization.

The two reactions resulted in block copolymers with few byproducts. In-situ 1H NMR revealed that the reactants in the first step (LLAOCA) were rapidly consumed during the first four hours (Step I, Figure 2a), and the concentration of PLLA increased notably. The concentration of PCHC only markedly increased after the concentration of PLLA saturated (Step II, Figure 2a). The byproduct of the second step, trans-cyclohexene carbonate, exhibited consistently low concentrations. The pronounced single peak in each size-exclusion chromatogram of the corresponding product confirmed the presence of block copolymers, instead of polymer mixtures (Figure 2b). Although the authors did not fully elucidate the origin of the excellent selectivity towards the block copolymer, they speculated that the change in CO2 partial pressure played a role. Significantly, nearly all CO2 molecules were consumed in the second step, with 91% incorporated into the block copolymer, and 9% converted to the byproduct.

Figure 2. (a) The evolution of the concentrations of PLLA, PCHC, and trans-CHC (the byproduct of the second step) with reaction time. (b) Size-exclusion chromatograms of the products at different reaction times. Mn: number-average molecular weight; Đ: polydispersity.

The authors are investigating the detailed polymerization mechanism, as well as identifying new catalysts to expand the polymerization scheme to other polymers.

 

To find out more, please read:

Waste Not, Want Not: CO2 (Re)cycling into Block Copolymers

Sumesh K. Raman, Robert Raja, Polly L. Arnold, Matthew G. Davidson, and Charlotte K. Williams

Chem. Commun., 2019, 55, 7315-7318

 

About the blogger:

Tianyu Liu obtained his Ph.D. (2017) in Chemistry from University of California, Santa Cruz in the United States. He is passionate about scientific communication to introduce cutting-edge research to both the general public and scientists with diverse research expertise. He is a blog writer for Chem. Commun. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

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Chemical Communications: Editor’s Choice

Featuring exciting research published in ChemComm, hand-picked by our Associate Editors as their favorite recent articles!

Be sure to read our Editor’s Choice articles as chosen by Associate Editors Prof. Jonathan Steed & Prof. Jonathan Sessler!

All articles are free-to-access until 31st August and can be found in our online Editor’s Choice web-collection!

Planar rings in nano-Saturns and related complexes” by Steven M. Bachrach, as chosen by Jonathan Steed:

“This paper lays down the gauntlet to synthetic chemists! The image of a nano-Saturn is immediately eye-catching and scales up molecular host guest chemistry to the multi-nanometre scale. This creative theoretical paper establishes that ortho-nitrogen substitution in aryl macrocycles creates large planar or ribbon structures and then goes on to show that these discs or rings can combine with other nanostructures to construct complexes with interesting shapes. Given the huge interest generated by the mechanically interlocked structures underlying the 2016 Nobel prize in chemistry, these large-scale included systems are real food for thought and I am excited to see if they can be realised experimentally.”

Enhancing selectivity of cation exchange with anion receptors” by 

“These researchers have shown that by using a classic anion binding agent, namely a calix[4]pyrrole, it is possible to modulate the inherent selectivity of liquid-liquid cation extractants. Most current extraction-based separations rely on the use of lipophilic anions as the extractants. These anions, typically the conjugate bases of carboxylic acids, beta-diketones, phosphoric/phosphonic/phosphinic acids, phenols, hydroxyoximes, and sulfonic acids, complex to the cation in question with a selectivity set largely by the local anion-cation coordination environment. However, in this communication the ORNL team has shown that when a calix[4]pyrrole is added to a phenolate-type cation extractant the inherent selectivity is pushed in favor of Cs+ over Na+. This bias in favor of Cs+, which stands in contrast to what would normally be expected, is rationalized in terms of the formation of a highly specific tertiary supramolecular complex involving the calix[4]pyrrole, the anionic phenolate, and the Cs+ cation. Such an organized ternary complex is disfavored in the case of Na+. This work is particularly appealing to me as an Associate Editor for its combination of novelty, insightfulness, and scholarly rigor. It is also attractive to me personally because it demonstrates a new utility for one of my favorite old-but-new molecules, namely calix[4]pyrrole.”

Bonus article: “p-Phosphonic acid calix[8]arene mediated synthesis of ultra-large, ultra-thin, single-crystal gold nanoplatelets” by  et al., as chosen by Jonathan Steed:

“This work reports a very simple system that gives glorious gold nanoplatelets with significant surface area but a thickness of around 6nm. Creating 2D nanocrystals is very challenging and involves highly kinetic conditions. In this case the simple reduction of soluble gold(III) in the presence of a phosphonated acid calix[8]arene macrocycle gives rise to these very well-defined and very unusual morphologies. In this case the role of the calixarene seems to be to attach to the Au(111) surfaces, impeding their growth in one direction and allowing growth in the other to form single-crystal platelets. We are still just scratching the surface of what unusual nanoscale morphologies can do to alter the properties of a material but the present gold nanowafers already show promise as oxygen sensors.”

Find our full Editor’s Choice collection online!

Keep up-to-date with our latest journal news on Twitter @ChemCommun!

Learn more about ChemComm online! Submit your latest high impact research here!

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Raffaella Buonsanti and Corinna Schindler: Winners of the ChemComm Emerging Investigator Lectureship 2019!

On behalf of the ChemComm Editorial Board, we are pleased to announce the winners of the 2019 ChemComm Emerging Investigator Lectureship – Raffaella Buonsanti and Corinna Schindler! Our warmest congratulations to Raffaella and Corinna!

Raffaella Buonsanti

Raffaella Buonsanti obtained her PhD in Nanochemistry in 2010 at the National Nanotechnology Laboratory, University of Salento. Afterwards, she moved to the US where she spent over five years at the Lawrence Berkeley National Laboratory, first as a postdoc and project scientist at the Molecular Foundry and after as a tenure-track staff scientist in the Joint Center for Artificial Photosynthesis.

She is currently a tenure-track Assistant Professor in the Institute of Chemical Sciences and Engineering at EPFL in Switzerland. Her group works at the interface of materials chemistry and catalysis, using colloidal chemistry tools to synthesize controlled and tunable nanocrystals and to advance the current knowledge on the electrocatalytic conversion of small molecules into value-added chemicals. You can also learn more about Raffaella’s group and research on Twitter @lnce_epfl.

 

 

 

Corinna Schindler

Corinna was awarded her PhD in 2010 at the ETH Zurich, where she worked with Professor Erick M. Carreira on the total synthesis of Banyaside B and Microcin SF608. She has been awarded several honors during her independent career, including a 2016 David and Lucile Packard Foundation Fellowship, a 2016 NSF CAREER award, a 2018 Alfred P. Sloan Research Fellowship, a 2018 Camille Dreyfus Teacher-Scholar Award, a 2019 Marion Milligan Mason Award, and a 2019 Presidential Early Career Award for Scientists and Engineers.

She is currently an Assistant Professor at the University of Michigan, Ann Arbor and her group’s research focuses on the development of new synthetic transformations relying on environmentally benign metals and the synthesis of complex molecules of biological importance in cancer treatment and infectious diseases. Find more info about Corinna and her group on Twitter @SchindlerLab.

 

 

 

 

As part of the Lectureship award, Raffaella and Corinna will each present lectures at three locations over the coming year, with at least one of these events taking place at an international conference. Details of the lectures will be announced in due course but keep an eye on Twitter @ChemCommun for details!

Keep up-to-date with our latest journal news on Twitter @ChemCommun or via our blog!

Learn more about ChemComm online! Submit your latest high impact research here!

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Guiding Light with Molecular Crystals

We’re all used to communications and computing happening at high, and seemingly ever-increasing speeds. Continuing on this trajectory requires the development of materials capable of acting as micro/nanoscale waveguides that don’t experience interference effects from strong external electromagnetic fields. Molecular crystals represent an exciting but relatively under-explored materials class due to their inherently limited emission and absorption properties. However, an international group of researchers recently combined two different crystalline materials with complementary optical properties in a filled-hollow crystal architecture, involving no binding materials or polymer matrices.

Figure 1. Spectra and structure of DCA (left) and PDI (right).

The group used 9,10-dicyanoanthracine (DCA) as the hollow outer crystal, with a perylene diimide derivative (PDI) as the interior compound (Figure 1). When combined, these two compounds exhibit fluorescence that covers the visible and near-IR portions of the electromagnetic spectrum. The researchers grew hollow crystals of DCA with diameters ranging from 50-400 μm in diameter with pores of 10-200 μm and filled them with 1-50 μm PDI crystal fibrils manually by hand(!) (Figure 2) (I honestly can’t imagine how many crystals ended up broken during that experimental learning curve!). The assembled structure for study had a single hollow DCA crystal filled with 18 individual PDI fibrils to create the waveguide.

Figure 2. Schematic of hollow crystal architecture (top) with demonstration of construction (bottom).

When the researchers excited the full structure with a 365 nm continuous wavelength LED, both crystal components emitted light that was guided down to the opposite end. The specific makeup of the spectrum depends on the point of illumination; only the excited compounds emit. This supports the active waveguiding capabilities of the materials. The emissive properties can also be controlled by changing the excitation wavelengths to exclude the absorbance of one of the molecular crystals. PDI can be selectively excited using light above 550 nm and both PDI and DCA act simply as passive waveguides for light in the infrared region of the spectrum, of particular importance for wireless communication. This study represents an exciting next step for organic molecular materials as optical waveguides with a new architecture for devices.

To find out more please read:

A filled organic crystal as a hybrid large-bandwidth optical waveguide

Luca Catalano, Patrick Commins, Stefan Schramm, Durga Prasad Karothu, Rachid Rezgui, Kawther Hadef and Panče Naumov

Chem. Commun, 2019, 55, 4921-4924.

About the blogger:

Beth Mundy is a PhD candidate in chemistry in the Cossairt lab at the University of Washington in Seattle, Washington. Her research focuses on developing new and better ways to synthesize nanomaterials for energy applications. She is often spotted knitting in seminars or with her nose in a good book. You can find her on Twitter at @BethMundySci.

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HOT Chemical Communication articles for April

All of the referee-recommended articles below are free to access until  15th August 2019.

Drastic lattice softening in mixed triazole ligand iron(II) spin crossover nanoparticles
Mario Piedrahita-Bello, Karl Ridier, Mirko Mikolasek, Gábor Molnár, William Nicolazzi, Lionel Salmon* and Azzedine Bousseksou*
Chem. Commun., 2019, 55, 4769-4772
DOI: 10.1039/C9CC01619H, Communication

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Highly symmetrical, 24-faceted, concave BiVO4 polyhedron bounded by multiple high-index facets for prominent photocatalytic O2 evolution under visible light
Jianqiang Hu, Huichao He, Liang Li, Xin Zhou,* Zhaosheng Li,* Qing Shen, Congping Wu, Adullah M. Asiri, Yong Zhou* and Zhigang Zou
Chem. Commun., 2019, 55, 4777-4780
DOI: 10.1039/C9CC01366K, Communication

 

 

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Controlling the morphological evolution of a particle-stabilized binary-component system
Tao Li,* Jason Klebes, Jure Dobnikar* and Paul S. Clegg
Chem. Commun., 2019, 55, 5575-5578
DOI: 10.1039/C9CC01519A, Communication

 

 

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Formation of enantioenriched alkanol with stochastic distribution of enantiomers in the absolute asymmetric synthesis under heterogeneous solid–vapor phase conditions
Yoshiyasu Kaimori, Yui Hiyoshi, Tsuneomi Kawasaki, Arimasa Matsumoto and Kenso Soai*
Chem. Commun., 2019, 55, 5223-5226
DOI: 10.1039/C9CC01875A, Communication

 

 

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Rapid screening of the hydrogen bonding strength of radicals by electrochemiluminescent probes
Qinghong Xu, Jiali Liang, Xu Teng, Xin Yue, Ming Lei, Caifeng Ding and Chao Lu*
Chem. Commun., 2019, 55, 5563-5566
DOI: 10.1039/C9CC01210A, Communication

 

 

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Photo-oxygenation inhibits tau amyloid formation
Takanobu Suzuki, Yukiko Hori, Taka Sawazaki, Yusuke Shimizu, Yu Nemoto, Atsuhiko Taniguchi, Shuta Ozawa, Youhei Sohma,* Motomu Kanai* and Taisuke Tomita*
Chem. Commun., 2019, 55, 6165-6168
DOI: 10.1039/C9CC01728C, Communication

 

 

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4th Annual UK Porous Materials Conference

This July saw the 4th Annual UK Porous Materials Conference (UKPorMat) held in Cardiff (1st-2nd July) by the RSC Porous Materials Interest Group!

The Annual UK Porous Materials Conference (UKPorMat), now in its 4th year, was held at Cardiff University on the 1st and 2nd of July 2019. The meeting, organised and chaired by the committee members of the RSC Porous Materials Interest Group, aims to bring together researchers working in the expanding field of porous materials, which includes metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), porous organic cages, porous organic polymers, polymers of intrinsic microporosity and much more.

The Royal Society of Chemistry was delighted to be a part of the event, sponsoring a number of poster and talk prizes:

  • Giulia Schukraft (Imperial College London) was awarded the ChemComm Poster Prize
  • Iona Doig (University of Southampton) was awarded the Materials Horizons Poster Prize
  • Alexander Thom (University of Glasgow) was awarded the CrystEngComm Poster Prize
  • Alex James (University of Sheffield) was awarded the Chemical Science Prize for Best Talk

Congratulations to all of the prize winners!

 

Giulia Schukraft (left) receiving the ChemComm prize from Chris Harding (right)

Iona Doig (right) receiving the Materials Horizons prize from Chris Harding (left)

Alexander Thom (left) receiving the CrystEngComm prize from Ross Forgan (right) Alex James (left) receiving the Chemical Science prize from Chris Harding (right)

Special thanks to the organizers and committee members of the RSC Porous Materials Interest Group:

Dr Thomas Bennett (University of Cambridge)

Dr Andrea Laybourn (University of Nottingham)

Dr Ross Forgan (University of Glasgow)

Dr Darren Bradshaw (University of Southampton)

Dr Tim Easun (Cardiff University)

Dr Timothy Johnson (Johnson Matthey Technology Centre)

Professor Tina Düren

Prize-winners at the close of the 4th Annual UK Porous Materials meeting (Cardiff, 1st-2nd July 2019)

 

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ChemComm: Our Vision

Chemical Communications has a proud tradition of quality, integrity and urgency within the chemical sciences. To reflect this, Editorial Board Chair, Véronique Gouverneur (University of Oxford) and our Editorial Board have re-defined our vision and scope to recognise our history and ambitious future!

Vision statement

“ChemComm is the Royal Society of Chemistry’s most cited journal, and has a long history of publishing exciting new findings of exceptional significance, across the breadth of chemistry.

With its Communication format, we recognise the importance of rapid disclosure of your work, and we are proud that our times to publication remain among the fastest in the field.

Our vision for ChemComm is to maintain our longstanding tradition of quality, trust and fairness, and we encourage you to join our community by publishing your most exciting research with us.”

Véronique Gouverneur, Editorial Board Chair

Scope

ChemComm is committed to publishing findings on new avenues of research, drawn from all major areas of chemical research, from across the world. Main research areas include (but are not limited to):

  • Analytical chemistry
  • Biomaterials chemistry
  • Bioorganic/medicinal chemistry
  • Catalysis
  • Chemical Biology
  • Coordination Chemistry
  • Crystal Engineering
  • Energy
  • Sustainable chemistry
  • Green chemistry
  • Inorganic chemistry
  • Inorganic materials
  • Main group chemistry
  • Nanoscience
  • Organic chemistry
  • Organic materials
  • Organometallics
  • Physical chemistry
  • Supramolecular chemistry
  • Synthetic methodology
  • Theoretical and computational chemistry

Learn more about ChemComm online! Submit your latest high impact research here!

Keep up-to-date with our latest journal news on Twitter @ChemCommun or via our blog!

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Targeting the Powerhouse of the Cell to Fight Cancer

Everyone knows that cancer as a disease is awful, but the side effects of currently utilized chemotherapies have their own horrors. Research into natural products as therapies have found some promising compounds, but they face barriers to practical use in patients. One particular molecule, artesunate (ART), recently showed high potential for anticancer activity when in the presence of iron. Unfortunately, ART has major problems that limit its current applicability, including low solubility in water and high instability in biologically relevant conditions.

One approach to get around these issues is to encapsulate the drug (pun intended) in a nanoparticle-based carrier. A carrier with a hydrophobic interior and hydrophilic exterior can bring higher concentrations of drugs with low solubility into a cell and protect them from deleterious conditions in the body. An additional benefit is the relative ease of incorporating targeting ligands into the particles during synthesis. This allows the drugs to only interact with specific cells or, in this specific case, the mitochondria within cells.

Figure 1. Schematic of the nanoparticle synthesis process complete with targeting ligand molecules. The anticancer agent is activated in the presence of iron.

Researchers in China have prepared approximately 200 nm nanoparticle carriers for ART (Figure 1) using triphenyl phosphonium (TPP) as a mitochondrial targeting ligand. These nanoparticles remained stable in biologically relevant conditions for a week, sufficient for in-vitro studies. The studies showed significant decreases in cancer cell growth when the nanoparticles were used compared to the ART alone. The nanoparticles with TPP on the surface showed the highest efficacy, particularly when coupled with iron treatment to activate the ART.

Figure 2. Images of cells exposed to nanoparticles with (bottom) and without (top) a targeting ligand filled with different fluorescent dyes. The increased brightness corresponds to higher uptake of the nanoparticles by the cells.

To further investigate the cell uptake pathway of the nanoparticles, the researchers added fluorescent dye molecules to the inside of the particles. Once the cells took up and ruptured the nanoparticles, the dyes were released and became visible to the researchers (Figure 2). The fluorescence was twice as great in cells exposed to the nanoparticles treated with the TPP targeting ligand, showing its value for cell uptake. The researchers also used fluorescent dyes that react with reactive oxygen species (ROSs), as their generation is how ART kills cancer cells. The in-vitro studies showed an over three-fold increase in fluorescence from reactions with ROSs which, combined with data showing higher rates of cell death, supports the increased activity of ART when combined with this nanoparticle architecture.

To find out more please read:

A mitochondria targeting artesunate prodrug-loaded nanoparticle exerting anticancer activity via iron-mediated generation of the reactive oxygen species

Zhigang Chen, Xiaoxu Kang, Yixin Wu, Haihua Xiao, Xuzi Cai, Shihou Seng, Xuefeng Wang and Shiguo Chen

Chem. Commun., 2019, 55, 4781 – 4784.

About the blogger:

 

Beth Mundy is a PhD candidate in chemistry in the Cossairt lab at the University of Washington in Seattle, Washington. Her research focuses on developing new and better ways to synthesize nanomaterials for energy applications. She is often spotted knitting in seminars or with her nose in a good book. You can find her on Twitter at @BethMundySci.

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HOT ChemComm articles for March

All of the referee-recommended articles below are free to access until Friday 21st June 2019.

Amperometric monitoring of vesicular dopamine release using a gold nanocone electrode
Nan Zhang, Wei Zhao, Cong-Hui Xu,* Jing-Juan Xu* and Hong-Yuan Chen
Chem. Commun., 2019, 55, 3461-3464
DOI: 10.1039/C9CC01280J, Communication

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Photo-writing self-erasable phosphorescent images using poly(N-vinyl-2-pyrrolidone) as a photochemically deoxygenating matrix
Jinxiong Lin, Shigang Wan, Wenfeng Liu and Wei Lu*
Chem. Commun., 2019, 55, 4299-4302
DOI: 10.1039/C9CC01388A, Communication

 

 

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Selective amidation by a photocatalyzed umpolung reaction
Debasish Ghosh, Rajesh Nandi, Saikat Khamarui, Sukla Ghosh and Dilip K. Maiti*
Chem. Commun., 2019, 55, 3883-3886
DOI: 10.1039/C9CC01079C, Communication

 

 

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A free radical alkylation of quinones with olefins
Shuai Liu, Tong Shen, Zaigang Luo and Zhong-Quan Liu*
Chem. Commun., 2019, 55, 4027-4030
DOI: 10.1039/C9CC01704F, Communication

 

 

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Probing transient non-native states in amyloid beta fiber elongation by NMR
Jeffrey R. Brender, Anirban Ghosh, Samuel A. Kotler, Janarthanan Krishnamoorthy, Swapna Bera, Vanessa Morris, Timir Baran Sil, Kanchan Garai, Bernd Reif, Anirban Bhunia* and Ayyalusamy Ramamoorthy*
Chem. Commun., 2019, 55, 4483-4486
DOI: 10.1039/C9CC01067J, Communication

 

 

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A nickel(II)-catalyzed asymmetric intramolecular Alder-ene reaction of 1,7-dienes
Wen Liu, Pengfei Zhou, Jiawen Lang, Shunxi Dong,* Xiaohua Liu and Xiaoming Feng*
Chem. Commun., 2019, 55, 4479-4482
DOI: 10.1039/C9CC01521C, Communication

 

 

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1+1>2: Bridging Constituents in Hetero-Structured Hydrogen Evolution Photocatalysts

Solar-driven water reduction is a sustainable method to acquire hydrogen fuel. An indispensable component of this reaction is the photocatalyst which drives spontaneous hydrogen gas evolution from water when illuminated. Hetero-structured materials consisting of two or more catalysts stand out as promising hydrogen evolution catalysts, due to the combined advantages of their constituents (e.g. enhanced light-absorption capability). Unfortunately, the weak adhesion between different components is the Achilles heel of conventional hetero-structured photocatalysts. It impedes electron transport from the photocatalysts to the nearby water molecules, hindering the catalytic activity.

A research group led by Xiao Xiao and Jian-Ping Zou from Nanchang Hangkong University of China has demonstrated a solution to the aforementioned challenge. They firmly connected two photocatalysts – Pt-loaded carbon nitride (CN) and the covalent organic framework CTF-1 – via amide bonds, resulting in a new type of hetero-structured photocatalyst, CN/CTF-1, which exhibited a hydrogen evolution rate approximately 3 times faster than those of conventional hetero-structured photocatalysts made of weakly bound CN and CTF-1.

The researchers adopted a two-step method to synthesize CN/CTF-1. They first reacted CTF-1 sheets with 4-aminobenzoic acid to graft carboxylic groups onto the surfaces of the CTF-1 sheets. A subsequent amide condensation between the amine groups of the CN and the carboxyl groups on the CTF-1 bridged the two components. The amide groups serve as electron transport pathways and facilitate the movement of photo-excited electrons from CTF-1 to CN (Figure 1a) which liberates hydrogen gas.

The covalent amide “bridges” gave CN/CTF-1 a fast hydrogen production rate. Quantitatively, when irradiated with a 300 W Xe lamp at 160 mW/cm2, CN/CTF-1 produced ~4 mmol H2 per gram of CN/CTF-1 after 4 h (0.85 mmol H2 h-1 gcatalyst-1), whereas under identical conditions, weakly adhered CN and CTF-1 sheets as well as a physical mixture of CN and CTF-1 all achieved H2 evolution rates of ~1 mmol H2 per gram of photocatalyst (0.30 mmol H2 h-1 gcatalyst-1) (Figure 1b).

Figure 1. (a) (Pt-loaded) CN sheets are covalently bound to CTF-1 sheets via amide bonds. These covalent bonds serve as electron transport “bridges” that facilitate the diffusion of photo-excited electrons from CTF-1 to CN. (b) H2 evolution rates of four photocatalysts: 1 – covalently bound CN/CTF-1; 2 and 3 –  weakly adhered CN and CTF-1; 4 – a physical mixture of CN and CTF-1.

The covalent bonding strategy is applicable to other coupling reactions such as the Friedel-Crafts reaction. This general method could create a new paradigm for designing and synthesizing high-performance hetero-structured photocatalysts.

 

To find out more please read:

A General Strategy via Chemically Covalent Combination for Constructing Heterostructured Catalysts with Enhanced Photocatalytic Hydrogen Evolution

Gang Zhou, Ling-Ling Zheng, Dengke Wang, Qiu-Ju Xing, Fei Li, Peng Ye, Xiao Xiao, Yan Li, and Jian-Ping Zou

Chem. Commun., 2019, 55, 4150-4153

About the blogger:

Tianyu Liu obtained his Ph.D. (2017) in Chemistry from University of California, Santa Cruz in the United States. He is passionate about scientific communication to introduce cutting-edge research to both the general public and scientists with diverse research expertise. He is a blog writer for Chem. Commun. and Chem. Sci. More information about him can be found at http://liutianyuresearch.weebly.com/.

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