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2. Modular, Multi-Robot Integration of Laboratories: An Autonomous Solid-State Workflow for Powder X-Ray Diffraction

Author

Lunt, Amy. M., Fakhruldeen, Hatem, Pizzuto, Gabriella, Longley, Louis, White, Alexander, Rankin, Nicola, Clowes, Rob, Alston, Ben, Gigli, Lucia, Day, Graeme M., Cooper, Andrew I., and Chong, Sam. Y.

Subjects
Computer Science - Robotics
Abstract

Automation can transform productivity in research activities that use liquid handling, such as organic synthesis, but it has made less impact in materials laboratories, which require sample preparation steps and a range of solid-state characterization techniques. For example, powder X-ray diffraction (PXRD) is a key method in materials and pharmaceutical chemistry, but its end-to-end automation is challenging because it involves solid powder handling and sample processing. Here we present a fully autonomous solid-state workflow for PXRD experiments that can match or even surpass manual data quality. The workflow involves 12 steps performed by a team of three multipurpose robots, illustrating the power of flexible, modular automation to integrate complex, multitask laboratories.

Published
2023

4. Computationally-Guided Synthetic Control over Pore Size in Isostructural Porous Organic Cages

Author

Slater, Anna G, Reiss, Paul S, Pulido, Angeles, Little, Marc A, Holden, Daniel L, Chen, Linjiang, Chong, Samantha Y, Alston, Ben M, Clowes, Rob, Haranczyk, Maciej, Briggs, Michael E, Hasell, Tom, Day, Graeme M, and Cooper, Andrew I

Subjects
Inorganic Chemistry, Chemical Sciences, Chemical sciences
Abstract

The physical properties of 3-D porous solids are defined by their molecular geometry. Hence, precise control of pore size, pore shape, and pore connectivity are needed to tailor them for specific applications. However, for porous molecular crystals, the modification of pore size by adding pore-blocking groups can also affect crystal packing in an unpredictable way. This precludes strategies adopted for isoreticular metal-organic frameworks, where addition of a small group, such as a methyl group, does not affect the basic framework topology. Here, we narrow the pore size of a cage molecule, CC3, in a systematic way by introducing methyl groups into the cage windows. Computational crystal structure prediction was used to anticipate the packing preferences of two homochiral methylated cages, CC14-R and CC15-R, and to assess the structure-energy landscape of a CC15-R/CC3-S cocrystal, designed such that both component cages could be directed to pack with a 3-D, interconnected pore structure. The experimental gas sorption properties of these three cage systems agree well with physical properties predicted by computational energy-structure-function maps.

Published
2017

5. A mobile robotic chemist

Author

Burger, Benjamin, Maffettone, Phillip M., Gusev, Vladimir V., Aitchison, Catherine M., Bai, Yang, Wang, Xiaoyan, Li, Xiaobo, Alston, Ben M., Li, Buyi, Clowes, Rob, Rankin, Nicola, Harris, Brandon, Sprick, Reiner Sebastian, and Cooper, Andrew I.

Published
2020
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11. How Reproducible are Surface Areas Calculated from the BET Equation?

Author

Universidad de Alicante. Departamento de Química Inorgánica, Osterrieth, Johannes W. M., Rampersad, James, Madden, David G., Rampal, Nakul, Skoric, Luka, Connolly, Bethany M., Allendorf, Mark D., Stavila, Vitalie, Snider, Jonathan L., Ameloot, Rob, Marreiros, João, Coudert, François-Xavier, Cui, Yong, Hou, Bang, D'Alessandro, Deanna M., Doheny, Patrick W., Dincă, Mircea, Sun, Chenyue, Doonan, Christian, Huxley, Michael Thomas, Evans, Jack D., Bara, Dominic, Falcaro, Paolo, Ricco, Raffaele, Farha, Omar, Idrees, Karam B., Islamoglu, Timur, Feng, Pingyun, Yang, Huajun, Forgan, Ross S., Furukawa, Shuhei, Sanchez, Eli, Gascon, Jorge, Telalović, Selvedin, Ghosh, Sujit K., Mukherjee, Soumya, Hill, Matthew R., Sadiq, Muhammed Munir, Horcajada, Patricia, DeWitt, Stephen J. A., Salcedo-Abraira, Pablo, Kaneko, Katsumi, Kukobat, Radovan, Kenvin, Jeff, Keskin, Seda, Kitagawa, Susumu, Otake, Ken-ichi, Lively, Ryan P., Llewellyn, Phillip L., Lotsch, Bettina V., Emmerling, Sebastian T., Pütz, Alexander M., Martí-Gastaldo, Carlos, Padial, Natalia M., Garcia-Martinez, Javier, Linares, Noemi, Maspoch, Daniel, Rosseinsky, Matthew J., Suárez del Pino, Jose A., Moghadam, Peyman Z., Oktavian, Rama, Morris, Russel E., Wheatley, Paul S., Navarro, Jorge, Petit, Camille, Danaci, David, Katsoulidis, Alexandros P., Schröder, Martin, Han, Xue, Yang, Sihai, Serre, Christian, Mouchaham, Georges, Sholl, David S., Thyagarajan, Raghuram, Siderius, Daniel, van der Veen, Monique A., Snurr, Randall Q., Goncalves, Rebecca B., Telfer, Shane, Lee, Seok J., Ting, Valeska P., Rowlandson, Jemma L., Uemura, Takashi, Iiyuka, Tomoya, Rega, Davide, Van Speybroeck, Veronique, Rogge, Sven M.J., Lamaire, Aran, Walton, Krista S., Bingel, Lukas W., Wuttke, Stefan, Andreo, Jacopo, Yaghi, Omar, Ania, Conchi O., Zhang, Bing, Yavuz, Cafer T., Nguyen, Thien S., Zamora, Félix, Montoro, Carmen, Zhou, Hongcai, Kirchon, Angelo, Fairen-Jimenez, David, Azevedo, Diana, Vilarrasa-García, Enrique, Santos, Bianca F., Bu, Xian-He, Chang, Ze, Bunzen, Hana, Champness, Neil R., Griffin, Sarah L., Chen, Banglin, Lin, Rui-Biao, Coasne, Benoit, Cohen, Seth, Moreton, Jessica C., Colón, Yamil J., Chen, Linjiang, Clowes, Rob, Universidad de Alicante. Departamento de Química Inorgánica, Osterrieth, Johannes W. M., Rampersad, James, Madden, David G., Rampal, Nakul, Skoric, Luka, Connolly, Bethany M., Allendorf, Mark D., Stavila, Vitalie, Snider, Jonathan L., Ameloot, Rob, Marreiros, João, Coudert, François-Xavier, Cui, Yong, Hou, Bang, D'Alessandro, Deanna M., Doheny, Patrick W., Dincă, Mircea, Sun, Chenyue, Doonan, Christian, Huxley, Michael Thomas, Evans, Jack D., Bara, Dominic, Falcaro, Paolo, Ricco, Raffaele, Farha, Omar, Idrees, Karam B., Islamoglu, Timur, Feng, Pingyun, Yang, Huajun, Forgan, Ross S., Furukawa, Shuhei, Sanchez, Eli, Gascon, Jorge, Telalović, Selvedin, Ghosh, Sujit K., Mukherjee, Soumya, Hill, Matthew R., Sadiq, Muhammed Munir, Horcajada, Patricia, DeWitt, Stephen J. A., Salcedo-Abraira, Pablo, Kaneko, Katsumi, Kukobat, Radovan, Kenvin, Jeff, Keskin, Seda, Kitagawa, Susumu, Otake, Ken-ichi, Lively, Ryan P., Llewellyn, Phillip L., Lotsch, Bettina V., Emmerling, Sebastian T., Pütz, Alexander M., Martí-Gastaldo, Carlos, Padial, Natalia M., Garcia-Martinez, Javier, Linares, Noemi, Maspoch, Daniel, Rosseinsky, Matthew J., Suárez del Pino, Jose A., Moghadam, Peyman Z., Oktavian, Rama, Morris, Russel E., Wheatley, Paul S., Navarro, Jorge, Petit, Camille, Danaci, David, Katsoulidis, Alexandros P., Schröder, Martin, Han, Xue, Yang, Sihai, Serre, Christian, Mouchaham, Georges, Sholl, David S., Thyagarajan, Raghuram, Siderius, Daniel, van der Veen, Monique A., Snurr, Randall Q., Goncalves, Rebecca B., Telfer, Shane, Lee, Seok J., Ting, Valeska P., Rowlandson, Jemma L., Uemura, Takashi, Iiyuka, Tomoya, Rega, Davide, Van Speybroeck, Veronique, Rogge, Sven M.J., Lamaire, Aran, Walton, Krista S., Bingel, Lukas W., Wuttke, Stefan, Andreo, Jacopo, Yaghi, Omar, Ania, Conchi O., Zhang, Bing, Yavuz, Cafer T., Nguyen, Thien S., Zamora, Félix, Montoro, Carmen, Zhou, Hongcai, Kirchon, Angelo, Fairen-Jimenez, David, Azevedo, Diana, Vilarrasa-García, Enrique, Santos, Bianca F., Bu, Xian-He, Chang, Ze, Bunzen, Hana, Champness, Neil R., Griffin, Sarah L., Chen, Banglin, Lin, Rui-Biao, Coasne, Benoit, Cohen, Seth, Moreton, Jessica C., Colón, Yamil J., Chen, Linjiang, and Clowes, Rob

Abstract

Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer–Emmett–Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro- and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This round-robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called “BET surface identification” (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possible.

Published
2022

12. How Reproducible are Surface Areas Calculated from the BET Equation?

Author

European Commission, European Research Council, University of Cambridge, Trinity College Cambridge, National Nuclear Security Administration (US), Department of Energy (US), Alexander von Humboldt Foundation, Center for Advancing Electronics Dresden, Science and Engineering Research Board (India), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Universidad de Alicante, Research Foundation - Flanders, Engineering and Physical Sciences Research Council (UK), National Research Foundation of Korea, Indonesia Endowment Fund for Education, National Institute of Standards and Technology (US), Osterrieth, Johannes W. M., Rampersad, James, Madden, David, Rampal, Nakul, Skoric, Luka, Connolly, Bethany, Allendorf, Mark D., Stavila, Vitalie, Snider, Jonathan L., Ameloot, Rob, Marreiros, João, Bara, Dominic, Furukawa, Shuhei, Sánchez, Eli, Gascón, Jorge, Telalović, Selvedin, Ghosh, Sujit K., Mukherjee, Soumya, Hill, Matthew R., Sadiq, Muhammed Munir, Horcajada, Patricia, DeWitt, Stephen J. A., Salcedo Abraira, Pablo, Kaneko, Katsumi, Kukobat, Radovan, Kenvin, Jeff, Keskin, Seda, Kitagawa, Susumu, Otake, Ken-Ichi, Lively, Ryan P., Llewellyn, Phillip, Lotsch, Bettina V., Emmerling, Sebastian T., Pütz, Alexander M., Martí-Gastaldo, Carlos, Padial, Natalia M., García-Martínez, Javier, Linares, Noemí, Maspoch, Daniel, Rosseinsky, Matthew J., Suárez, José Antonio, Moghadam, Peyman, Oktavian, Rama, Morris, Russell E., Wheatley, Paul S., Navarro, Jorge, Petit, Camille, Danaci, David, Katsoulidis, Alexandros P., Schröder, Martin, Han, Xue, Yang, Sihai, Serre, Christian, Mouchaham, Georges, Sholl, David S., Thyagarajan, Raghuram, Siderius, Daniel, Veen, Monique A. van der, Snurr, Randall Q., Goncalves, Rebecca B., Telfer, Shane, Lee, Seok J., Ting, Valeska P., Rowlandson, Jemma L., Uemura, Takashi, Iiyuka, Tomoya, Rega, Davide, Speybroeck, Veronique van, Rogge, Sven M. J., Lamaire, Aran, Walton, Krista S., Bingel, Lukas W., Wuttke, Stefan, Andreo, Jacopo, Yaghi, Omar, Ania, Conchi O., Zhang, Bing, Yavuz, Cafer T., Nguyen, Thien S., Zamora, Félix, Montoro, Carmen, Zhou, Hongcai, Kirchon, Angelo, Fairen-Jiménez, David, Azevedo, Diana, Vilarrasa-García, E., Santos, Bianca S., Bu, Xian-He, Chang, Ze, Bunzen, Hana, Champness, Neil R., Griffin, Sarah L., Chen, Banglin, Lin, Rui-Biao, Coasne, Benoit, Cohen, Seth, Moreton, Jessica C., Colón, Yamil J., Chen, Linjiang, Clowes, Rob, Coudert, François Xavier, Cui, Yong, Hou, Bang, D'Alessandro, Deanna M., Doheny, Patrick W., Dincă, Mircea, Sun, Chenyue, Doonan, Christian J., Huxley, Michael Thomas, Evans, Jack D., Falcaro, Paolo, Ricco, Raffaele, Farha, Omar, Idrees, Karam B., Islamoglu, Timur, Feng, Pingyun, Chang, Huajun, Forgan, Ross S., European Commission, European Research Council, University of Cambridge, Trinity College Cambridge, National Nuclear Security Administration (US), Department of Energy (US), Alexander von Humboldt Foundation, Center for Advancing Electronics Dresden, Science and Engineering Research Board (India), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Universidad de Alicante, Research Foundation - Flanders, Engineering and Physical Sciences Research Council (UK), National Research Foundation of Korea, Indonesia Endowment Fund for Education, National Institute of Standards and Technology (US), Osterrieth, Johannes W. M., Rampersad, James, Madden, David, Rampal, Nakul, Skoric, Luka, Connolly, Bethany, Allendorf, Mark D., Stavila, Vitalie, Snider, Jonathan L., Ameloot, Rob, Marreiros, João, Bara, Dominic, Furukawa, Shuhei, Sánchez, Eli, Gascón, Jorge, Telalović, Selvedin, Ghosh, Sujit K., Mukherjee, Soumya, Hill, Matthew R., Sadiq, Muhammed Munir, Horcajada, Patricia, DeWitt, Stephen J. A., Salcedo Abraira, Pablo, Kaneko, Katsumi, Kukobat, Radovan, Kenvin, Jeff, Keskin, Seda, Kitagawa, Susumu, Otake, Ken-Ichi, Lively, Ryan P., Llewellyn, Phillip, Lotsch, Bettina V., Emmerling, Sebastian T., Pütz, Alexander M., Martí-Gastaldo, Carlos, Padial, Natalia M., García-Martínez, Javier, Linares, Noemí, Maspoch, Daniel, Rosseinsky, Matthew J., Suárez, José Antonio, Moghadam, Peyman, Oktavian, Rama, Morris, Russell E., Wheatley, Paul S., Navarro, Jorge, Petit, Camille, Danaci, David, Katsoulidis, Alexandros P., Schröder, Martin, Han, Xue, Yang, Sihai, Serre, Christian, Mouchaham, Georges, Sholl, David S., Thyagarajan, Raghuram, Siderius, Daniel, Veen, Monique A. van der, Snurr, Randall Q., Goncalves, Rebecca B., Telfer, Shane, Lee, Seok J., Ting, Valeska P., Rowlandson, Jemma L., Uemura, Takashi, Iiyuka, Tomoya, Rega, Davide, Speybroeck, Veronique van, Rogge, Sven M. J., Lamaire, Aran, Walton, Krista S., Bingel, Lukas W., Wuttke, Stefan, Andreo, Jacopo, Yaghi, Omar, Ania, Conchi O., Zhang, Bing, Yavuz, Cafer T., Nguyen, Thien S., Zamora, Félix, Montoro, Carmen, Zhou, Hongcai, Kirchon, Angelo, Fairen-Jiménez, David, Azevedo, Diana, Vilarrasa-García, E., Santos, Bianca S., Bu, Xian-He, Chang, Ze, Bunzen, Hana, Champness, Neil R., Griffin, Sarah L., Chen, Banglin, Lin, Rui-Biao, Coasne, Benoit, Cohen, Seth, Moreton, Jessica C., Colón, Yamil J., Chen, Linjiang, Clowes, Rob, Coudert, François Xavier, Cui, Yong, Hou, Bang, D'Alessandro, Deanna M., Doheny, Patrick W., Dincă, Mircea, Sun, Chenyue, Doonan, Christian J., Huxley, Michael Thomas, Evans, Jack D., Falcaro, Paolo, Ricco, Raffaele, Farha, Omar, Idrees, Karam B., Islamoglu, Timur, Feng, Pingyun, Chang, Huajun, and Forgan, Ross S.

Abstract

Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer–Emmett–Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro- and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This round-robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called “BET surface identification” (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possible.

Published
2022

13. A stable covalent organic framework for photocatalytic carbon dioxide reduction† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c9sc03800k

Author

Fu, Zhiwei, Wang, Xiaoyan, Gardner, Adrian M., Wang, Xue, Chong, Samantha Y., Neri, Gaia, Cowan, Alexander J., Liu, Lunjie, Li, Xiaobo, Vogel, Anastasia, Clowes, Rob, Bilton, Matthew, Chen, Linjiang, Sprick, Reiner Sebastian, and Cooper, Andrew I.

Subjects
Chemistry
Abstract

A metal-decorated alkene-linked covalent organic framework is a robust, selective photocatalyst for CO2 reduction., Photocatalytic conversion of CO2 into fuels is an important challenge for clean energy research and has attracted considerable interest. Here we show that tethering molecular catalysts—a rhenium complex, [Re(bpy)(CO)3Cl]—together in the form of a crystalline covalent organic framework (COF) affords a heterogeneous photocatalyst with a strong visible light absorption, a high CO2 binding affinity, and ultimately an improved catalytic performance over its homogeneous Re counterpart. The COF incorporates bipyridine sites, allowing for ligation of the Re complex, into a fully π-conjugated backbone that is chemically robust and promotes light-harvesting. A maximum rate of 1040 μmol g–1 h–1 for CO production with 81% selectivity was measured. CO production rates were further increased up to 1400 μmol g–1 h–1, with an improved selectivity of 86%, when a photosensitizer was added. Addition of platinum resulted in production of syngas, hence, the co-formation of H2 and CO, the chemical composition of which could be adjusted by varying the ratio of COF to platinum. An amorphous analog of the COF showed significantly lower CO production rates, suggesting that crystallinity of the COF is beneficial to its photocatalytic performance in CO2 reduction.

Published
2019

14. Functional materials discovery using energystructurefunction maps

Author

Pulido, Angeles, Chen, Linjiang, Kaczorowski, Tomasz, Holden, Daniel, Little, Marc A., Chong, Samantha Y., Slater, Benjamin J., McMahon, David P., Bonillo, Baltasar, Stackhouse, Chloe J., Stephenson, Andrew, Kane, Christopher M., Clowes, Rob, Hasell, Tom, Cooper, Andrew I., and Day, Graeme M.

Subjects
Structure, Atomic properties, Molecular crystals -- Atomic properties -- Structure, Crystal structure
Abstract

Author(s): Angeles Pulido [1]; Linjiang Chen [2]; Tomasz Kaczorowski [2]; Daniel Holden [2]; Marc A. Little [2]; Samantha Y. Chong [2]; Benjamin J. Slater [2]; David P. McMahon [1]; Baltasar [...], Molecular crystals cannot be designed in the same manner as macroscopic objects, because they do not assemble according to simple, intuitive rules. Their structures result from the balance of many weak interactions, rather than from the strong and predictable bonding patterns found in metalorganic frameworks and covalent organic frameworks. Hence, design strategies that assume a topology or other structural blueprint will often fail. Here we combine computational crystal structure prediction and property prediction to build energystructurefunction maps that describe the possible structures and properties that are available to a candidate molecule. Using these maps, we identify a highly porous solid, which has the lowest density reported for a molecular crystal so far. Both the structure of the crystal and its physical properties, such as methane storage capacity and guest-molecule selectivity, are predicted using the molecular structure as the only input. More generally, energystructurefunction maps could be used to guide the experimental discovery of materials with any target function that can be calculated from predicted crystal structures, such as electronic structure or mechanical properties.

Published
2017
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15. An Expandable Hydrogen-Bonded Organic Framework Characterized by Three-Dimensional Electron Diffraction

Author

Cui, Peng, Svensson Grape, Erik, Spackman, Peter R., Wu, Yue, Clowes, Rob, Day, Graeme M., Inge, A. Ken, Little, Marc A., Cooper, Andrew, Cui, Peng, Svensson Grape, Erik, Spackman, Peter R., Wu, Yue, Clowes, Rob, Day, Graeme M., Inge, A. Ken, Little, Marc A., and Cooper, Andrew

Abstract

A molecular crystal of a 2-D hydrogen-bonded organic framework (HOF) undergoes an unusual structural transformation after solvent removal from the crystal pores during activation. The conformationally flexible host molecule, ABTPA, adapts its molecular conformation during activation to initiate a framework expansion. The microcrystalline activated phase was characterized by three-dimensional electron diffraction (3D ED), which revealed that ABTPA uses out-of-plane anthracene units as adaptive structural anchors. These units change orientation to generate an expanded, lower density framework material in the activated structure. The porous HOF, ABTPA-2, has robust dynamic porosity (SA(BET) = 1 183 m(2) g(-1)) and exhibits negative area thermal expansion. We use crystal structure prediction (CSP) to understand the underlying energetics behind the structural transformation and discuss the challenges facing CSP for such flexible molecules.

Published
2020
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16. A stable covalent organic framework for photocatalytic carbon dioxide reduction

Author

Fu, Zhiwei, primary, Wang, Xiaoyan, additional, Gardner, Adrian M., additional, Wang, Xue, additional, Chong, Samantha Y., additional, Neri, Gaia, additional, Cowan, Alexander J., additional, Liu, Lunjie, additional, Li, Xiaobo, additional, Vogel, Anastasia, additional, Clowes, Rob, additional, Bilton, Matthew, additional, Chen, Linjiang, additional, Sprick, Reiner Sebastian, additional, and Cooper, Andrew I., additional

Published
2020
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17. Nitrogen Containing Linear Poly(phenylene) Derivatives for Photo-catalytic Hydrogen Evolution from Water

Author

Sprick, Reiner Sebastian, Wilbraham, Liam, Bai, Yang, Guiglion, Pierre, Monti, Adriano, Clowes, Rob, Cooper, Andrew I., and Zwijnenburg, Martijn A.

Subjects
QD
Abstract

Here we study how the introduction of nitrogen into poly(p-phenylene) type materials affects their ability to act as hydrogen evolution photocatalysts. Direct photocatalytic water splitting is an attractive strategy for clean energy production, but understanding which material properties are important, how they interplay, and how they can be influenced through doping remains a significant challenge, especially for polymers. Using a combined experimental and computational approach, we demonstrate that introducing nitrogen in conjugated polymers results in either materials that absorb significantly more visible light but worse predicted driving force for water/sacrificial electron donor oxidation, or materials with an improved driving force that absorb relatively less visible light. The latter materials are found to be much more active and the former much less. The trade-off between properties highlights that the optimization of a single property in isolation is a poor strategy for improving the overall activity of materials.

Published
2018

18. Corrigendum : Visible-light-driven hydrogen evolution using planarized conjugated polymer photocatalysts (Angewandte Chemie International Edition, (2016), 55, 5, (1792-1796), 10.1002/anie.201510542)

Author

Sprick, Reiner Sebastian, Bonillo, Baltasar, Clowes, Rob, Guiglion, Pierre, Brownbill, Nick J., Slater, Benjamin J., Blanc, Frédéric, Zwijnenburg, Martijn A., Adams, Dave J., and Cooper, Andrew I.

Subjects
QD
Abstract

The authors regret that incorrect data was presented in Figure, Figure, and Table of this Communication. The corrected Figures and Table entries are shown below. The hydrogen evolution rates were incorrectly calculated, but by a common scaling factor. Hence, the trends observed between materials and the overall conclusions made in the Communication remain valid. The correct H2 evolution rate for the most active polymer, P7, under visible light (>420 nm) should be 37.3 μmol h−1 (1492 μmol g−1 h−1), not 92.0 μmol h−1 as initially reported. The apparent quantum yields at 420 nm for P1K, P6, and P7 should be corrected to 0.4 % (±0.1 %), 2.2 % (±0.2 %), and 7.2 % (±0.3 %), respectively. Figure (Figure presented.) Photocatalytic hydrogen evolution rates. Each measurement was performed with 25 mg catalyst in water/MeOH/triethylamine mixture under broad-spectrum irradiation (λ>295 nm; see Table for visible light HERs). Figure (Figure presented.) a) Time-course for photocatalytic H2 production using visible light for P1K, P6, and P7 (25 mg catalyst in water/MeOH/triethylamine mixture λ>420 nm). b) P6 and P7 (25 mg catalyst in water/MeOH/triethylamine mixture; λ>420 nm), photolysis run for a total of 65 h. Photophysical properties and hydrogen evolution rates (HERs) for the polymer photocatalysts. (Table presented.) … [c] Reaction conditions: 25 mg polymer was suspended in water/MeOH/triethylamine solution, irradiated by 300 W Xe lamp for 5 hours using a suitable filter. The most active polymer, P7, was studied independently by another research group, who reported an apparent quantum yield of 6.61 %, close to the corrected value of 7.2 %. The precise value of the apparent quantum yield and hence the H2 evolution rate will depend on the details of the experimental set up and the irradiation intensity.

Published
2018

19. Porous organic cages for sulfur hexafluoride separation

Author

Hasell, Tom, Miklitz, Marcin, Stephenson, Andrew, Little, Marc A, Chong, Samantha Y, Clowes, Rob, Chen, Linjiang, Holden, Daniel, Tribello, Gareth A, Jelfs, Kim E, Cooper, Andrew I, and The Royal Society

Subjects
General Chemistry, 03 Chemical Sciences
Abstract

A series of porous organic cages is examined for the selective adsorption of sulphur hexafluoride (SF6) over nitrogen. Despite lacking any metal sites, a porous cage, CC3, shows the highest SF6/N2 selectivity reported for any material at ambient temperature and pressure, which translates to real separations in a gas breakthrough column. The SF6 uptake of these materials is considerably higher than would be expected from the static pore structures. The location of SF6 within these materials is elucidated by x-ray crystallography, and it is shown that cooperative diffusion and structural rearrangements in these molecular crystals can rationalize their superior SF6/N2 selectivity.

Published
2016
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20. A soft porous organic cage crystal with complex gas sorption behavior

Author

Mitra, Tamoghna, Wu, Xiaofeng, Clowes, Rob, Jones, James T. A., Jelfs, Kim E., Adams, Dave J., Trewin, Abbie, Bacsa, John, Steiner, Alexander, Cooper, Andrew I., Mitra, Tamoghna, Wu, Xiaofeng, Clowes, Rob, Jones, James T. A., Jelfs, Kim E., Adams, Dave J., Trewin, Abbie, Bacsa, John, Steiner, Alexander, and Cooper, Andrew I.

Abstract

Big softy! A soft porous molecular crystal composed of organic cages exhibits complex multistep gas sorption isotherms (see figure), analogous to those observed in soft porous metal–organic frameworks. Softness is induced by frustrated packing of the cages and structural flexibility leads to kinetic guest trapping.

Published
2011

21. Scaffolding Cognition with Words

Author

Clowes, Robert, Morse, Anthony F., Berthouze, Luc, Kaplan, Frédéric, Kozima, Hideki, Yano, Hiroyuki, Konczak, Jürgen, Metta, Giorgio, Nadel, Jacqueline, Sandini, Giulio, Stojanov, Georgi, and Balkenius, Christian

Subjects
Computer Science: Language, Psychology: Developmental Psychology, Computer Science: Robotics, Language, Developmental Psychology, Robotics
Abstract

We describe a set of experiments investigating the role of natural language symbols in scaffolding situated action. Agents are evolved to respond appropriately to commands in order to perform simple tasks. We explore three different conditions, which show a significant advantage to the re-use of a public symbol system, through self-cueing leading to qualitative changes in performance. This is modelled by looping spoken output via environment back to heard input. We argue this work can be linked to, and sheds new light on, the account of self-directed speech advanced by the developmental psychologist Vygotsky in his model of the development of higher cognitive function.

Published
2005

22. Porous organic cages

Author

Tozawa, Tomokazu, Swamy, Shashikala, Jiang, Shan, Adams, Dave J., Shakespeare, Stephen, Jones, James T. A., Clowes, Rob, Bradshaw, Darren, Hasell, Tom, Bacsa, John, Trewin, Abbie, Slawin, Alexandra Mz., Steiner, Alexander, Cooper, Andrew I., Tozawa, Tomokazu, Swamy, Shashikala, Jiang, Shan, Adams, Dave J., Shakespeare, Stephen, Jones, James T. A., Clowes, Rob, Bradshaw, Darren, Hasell, Tom, Bacsa, John, Trewin, Abbie, Slawin, Alexandra Mz., Steiner, Alexander, and Cooper, Andrew I.

Published
2009

23. High surface area amorphous microporous poly(aryleneethynylene) networks using tetrahedral carbon- and silicon-centred monomers

Author

Stoeckel, Ev, Wu, Xiaofeng, Trewin, Abbie, Wood, Colin D., Clowes, Rob, Campbell, Neil L., Jones, James T. A., Khimyak, Yaroslav Z., Adams, Dave J., Cooper, Andrew I., Stoeckel, Ev, Wu, Xiaofeng, Trewin, Abbie, Wood, Colin D., Clowes, Rob, Campbell, Neil L., Jones, James T. A., Khimyak, Yaroslav Z., Adams, Dave J., and Cooper, Andrew I.

Abstract

Poly(aryleneethynylene) networks prepared from tetrahedral monomers are highly microporous and exhibit apparent Brunauer-Emmett-Teller surface areas of up to 1213 m(2) g(-1).

Published
2009

24. Action Oriented Adaptive Language Games

Author

Clowes, Robert, Prince, Christopher G., Berthouze, Luc, Kozima, Hideki, Bullock, Daniel, Stojanov, Georgi, and Balkenius, Christian

Subjects
Computer Science: Language, Computer Science: Robotics, Language, Robotics
Published
2003

26. Modular, multi-robot integration of laboratories: an autonomous workflow for solid-state chemistry.

Author

Lunt AM, Fakhruldeen H, Pizzuto G, Longley L, White A, Rankin N, Clowes R, Alston B, Gigli L, Day GM, Cooper AI, and Chong SY

Abstract

Automation can transform productivity in research activities that use liquid handling, such as organic synthesis, but it has made less impact in materials laboratories, which require sample preparation steps and a range of solid-state characterization techniques. For example, powder X-ray diffraction (PXRD) is a key method in materials and pharmaceutical chemistry, but its end-to-end automation is challenging because it involves solid powder handling and sample processing. Here we present a fully autonomous solid-state workflow for PXRD experiments that can match or even surpass manual data quality, encompassing crystal growth, sample preparation, and automated data capture. The workflow involves 12 steps performed by a team of three multipurpose robots, illustrating the power of flexible, modular automation to integrate complex, multitask laboratories., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Published
2023
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27. Porous silica spheres in macroporous structures and on nanofibres.

Author

Ahmed A, Clowes R, Willneff E, Myers P, and Zhang H

Abstract

Porous nanospheres have a wide range of applications such as in catalysis, separation and controlled delivery. Among these nanospheres, syntheses and applications of porous silica nanospheres have been investigated extensively. Uniform porous silica nanospheres can be synthesized using a modified Stöber method. In the present study, porous silica spheres were prepared in the pre-formed emulsion-templated porous polyacrylamide (PAM). A hierarchical hybrid structure of mesoporous silica spheres was formed in the highly interconnected macroporous polymer. The polymer scaffold could be removed by calcination with porous silica spheres and the macroporous structures retained. This resulted from the close packing or aggregation of small silica nanospheres in the pores and on the surface of pores of PAM. The modified Stöber synthesis was further carried out in pre-formed polymer nanofibres (chitosan and sodium carboxymethyl cellulose). The structure of porous silica spheres on nanofibres was produced in the presence of the polymer or composite fibres. The corresponding inorganic structures were successfully obtained after calcination. The hierarchical structures of porous nanospheres within macroporous structures or on nanofibres are of potential interest to researchers in nanomaterials, porous polymers, supported catalysis and controlled delivery.

Published
2010
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