Subscriber access provided by University of Newcastle, Australia
Letter
Tandem Nitrogen Functionalization of Porous Carbon: Toward Immobilizing Highly Active Palladium Nanoclusters for Dehydrogenation of Formic Acid Zhangpeng Li, Xinchun Yang, Nobuko Tsumori, Zheng Liu, Yuichiro Himeda, Tom Autrey, and Qiang Xu ACS Catal., Just Accepted Manuscript • DOI: 10.1021/acscatal.7b00053 • Publication Date (Web): 10 Mar 2017 Downloaded from http://pubs.acs.org on March 10, 2017
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
ACS Catalysis is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
ACS Catalysis
Tandem Nitrogen Functionalization of Porous Carbon: Toward Immobilizing Highly Active Palladium Nanoclusters for Dehydrogenation of Formic Acid Zhangpeng Li,† Xinchun Yang,† Nobuko Tsumori,‡ Zheng Liu,§ Yuichiro Himeda,⊥ Tom Autrey,║ and Qiang Xu*,† †
Research Institute of Electrochemical Energy, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan ‡ Toyama National College of Technology, 13, Hongo-machi, Toyama 939-8630, Japan § Inorganic Functional Materials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya, Aichi 463-8560, Japan Research Institute of Energy Frontier, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5-1, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan ║ Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99352, USA ⊥
ABSTRACT: Highly dispersed palladium nanoclusters (Pd NCs) immobilized by a nitrogen (N)-functionalized porous carbon support (N-MSC-30) are synthesized by a wet-chemical reduction method, wherein the N-MSC-30 prepared by a tandem lowtemperature heat-treatment approach proved to be a distinct support for stabilizing the Pd NCs. The prepared Pd/N-MSC-30 shows extremely high catalytic activity and recyclability for the dehydrogenation of formic acid (FA), affording the highest turnover frequency (TOF) value of 8414 h-1 at 333 K, which is much higher than that of Pd catalyst supported on the N-MSC-30 prepared by one-step process. This tandem heat-treatment strategy provides a facile and effective synthetic methodology to immobilize ultrafine metal NPs on N-functionalized carbon materials, which have tremendous application prospect in various catalytic fields.
KEYWORDS: nitrogen-functionalization, porous carbon, heterogeneous catalysis, palladium, formic acid, dehydrogenation The synthesis of supported transition metal nanoparticles (NPs) has drawn considerable attention in catalytic applications in part due to several unique properties. In particular, metal nanoclusters (NCs), with sizes range from subnanometer to about 2 nm, have received increasing attention due to their novel electrical structure, high fraction of surface atoms, and the quantum size effect, which can lead to extraordinary catalytic activity.1 However, the high surface energies of NPs/NCs can lead to severe aggregation during the catalytic processes, resulting in the loss of catalytic activity and recyclability. To date, several strategies have been developed to enable the effective synthesis of well-dispersed NCs; these include enhancing the metal-support interactions, using the confinement effect of the supports, and introducing organic capping agents.2 Despite the advances that have been achieved, it remains of interest the development of uncapped NCs by simple, efficient, and economical synthetic methods. Recently, nitrogen (N)-doped carbon matrixes have been successfully used as supports to synthesized metal NP catalysts for a wide range of important catalytic processes, such as oxidation, hydrogenation, and coupling reactions.3 N-containing functional groups can facilitate the anchoring of metal NPs functioning as basic coordination sites to stabilize the small metal NPs to achieve high activity. However, in most cases, the preparation of N-functionalized carbon requires high temperature or long pyrolysis time. To this end, an effective synthetic method for
N-functionalization of carbon materials would benefit both fundamental studies and industrial interests. Of special note, hydrogen and hydrogen storage materials have attracted increasing attention as a promising form for storing energy generated from renewable resources. The safe and efficient storage and transportation of hydrogen is a key but remains one of the most difficult challenges for realizing a hydrogen-powered society.4 Formic acid (FA), a major product of biomass processing, which can also be obtained by the direct CO2 hydrogenation, is regarded as a potential liquid carrier for hydrogen storage and delivery.5 The catalytic dehydrogenation of FA to generate hydrogen using heterogeneous catalysts is of interest by virtue of facile separation, recycling and low operating temperatures.6 However, most heterogeneous catalysts suffer from relatively low activity, poor recyclability (unstable), as well as requiring complex synthetic procedures. Palladium (Pd) and especially Pd-based nanoparticles have been demonstrated to be efficient H2 production catalysts of FA.6d-g,7 Recently, Cao and co-workers reported an engineered pyridinic-N-tuned Pd catalyst exhibiting high performance in FA dehydrogenation, indicating that N-doping plays an important role in this reaction.6g Thus far, there have only been a few reports of Pd nanoparticles with size of below 2 nm that are expected to be highly efficient with long-term stability for the dehydrogenation of FA. Herein, we report a facile and efficient tandem heat-
ACS Paragon Plus Environment
ACS Catalysis
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
treatment process to prepare N-functionalized MSC-30 carbon supports (N-MSC-30), which proved to be a robust support containing more stable N-functional groups than that in the counterpart prepared by one-step approach. We demonstrate that Pd NCs (with mean size of 1.4 nm) immobilized to the NMSC-30 supports are highly active and show long-term stability for the dehydrogenation of FA. Maxsorb MSC-30, features a large surface area, high stability, and accessible porosity,6d,8 that make the commercial available porous carbon a prime candidate for functionalization with nitrogen to accommodate and stabilize the Pd NCs. The resultant catalyst exhibits high activities with turnover frequency (TOF = 8414 h-1 at 333 K) for the complete decomposition of FA in heterogeneous systems. Furthermore, no obvious aggregation of Pd NCs was observed consistent with the finding of no loss in catalytic activity even after 15 cycles, showing excellent durability/stability. The superior catalytic performance is likely due to the ultra-small size and clean surface of the Pd NCs as well as synergistic effect between Pd NCs and the N-functionalized group anchored on the MSC-30 supports. The preparation of N-MSC-30 and immobilization of Pd NCs to N-MSC-30 are illustrated in Scheme 1. Nfunctionalized MSC-30 is prepared by a facile tandem heattreatment method (see the Supporting Information for details). Briefly, MSC-30 was thermally treated with urea at 300 oC (denoted as N-MSC-30-one),9 followed by a second ureatreatment process at different temperatures to yield N-MSC-30 support (denoted as N-MSC-30-two-T, T is the temperature used in the second heat-treatment step, and T = 150, 175, 200, 250, and 300 oC). Pd/N-MSC-30 catalysts were prepared by a typical wet-chemical impregnation and reduction method. Namely, 100 mg of the as-prepared support materials were dispersed into 5 mL H2O by sonication and then mixed with 0.6 mL of K2PdCl4 aqueous solution (0.1 M) to form a homogeneous dispersion. Subsequently, 30 mg NaBH4 in 1 mL of 2 M NaOH was added into the above dispersion. The mixture was shaken vigorously to produce the catalysts for dehydrogenation of FA.
Scheme 1. Schematic Illustration of the Immobilization of Pd NPs/NCs to the MSC-30 and N-Functionalized MSC30. It is notable that only one weak and broad diffraction peak for Pd is observed around 2θ = 40o attributed to (111) reflection (JCPDS no. 46-1043), indicating the absence of large size Pd particles in the Pd/N-MSC-30-two-175 catalyst (Figure 1a) In contrast, the XRD patterns of Pd/MSC-30, Pd/N-MSC-30one and other Pd/N-MSC-30-two-T samples exhibit distinct
Page 2 of 6
diffraction peaks for Pd phase (Figure 1a and S1), confirming formation of much larger NPs compared to the Pd/N-MSC-30two-175 counterpart, which presumably lead to relatively poor catalytic performance (vide infra). X-ray photoelectron spectroscopy (XPS) analyses of the asprepared samples were measured to determine the chemical states of the as-prepared samples. The XPS spectra of N 1s core level are presented in Figure 1b. Two different nitrogen species, with fitted peaks located at 400.0 and 398.7 eV, are detected in the Pd/N-MSC-30-one and Pd/N-MSC-30-two-175 catalysts, which are assigned to amine/amide groups, and pyridinic N, respectively.9 The fitting of the high-resolution Pd 3d spectra shows a doublet corresponding to the Pd 3d5/2 and Pd 3d3/2 (Figure 1c). The Pd 3d5/2 peak with a binding energy of 335.9 eV is attributed Pd0 (metallic palladium), while the 3d5/2 peak at 337.5 eV is attributed to Pd2+. The presence of Pd2+ in Pd/N-MSC-30 can be attributed to the oxidation of the surface Pd NCs in air due to its high activity and the strong interactions between the Pd precursors and the N functionalities making it difficult to reduce the Pd2+.3b
Figure 1. (a) XRD patterns, (b) N 1s and (c) Pd 3d XPS spectra of the as-prepared Pd/MSC-30 (1), Pd/N-MSC-30-one (2), and Pd/N-MSC-30-two-175 (3) catalysts, (d and e) HAADF-STEM images and (f) corresponding size distribution of Pd NCs of Pd/NMSC-30-two-175 catalyst.
The structure and morphology of the prepared catalysts were further investigated by transmission electron microscopy (TEM) and high-angle annular dark-field scanning TEM (HAADF-STEM). The HAADF-STEM and high resolution TEM (HRTEM) images of Pd/N-MSC-30-two-175 are shown in Figures 1d, 1e and S2. It can be seen that Pd NCs are homogenously distributed throughout the N-MSC-30-two-175 support, giving a narrow size distribution with the mean diameter of 1.4 nm (Figure 1f). In contrast, larger Pd NPs with a mean size of 2.6 nm are observed in the Pd/MSC-30 catalyst prepared under identical synthetic conditions (Figure S3). Nobably, although Pd NCs are observed in Pd/N-MSC-30-one (Figure S4a-c), some large particles are also present (Figure S4d), indicating aggregation occurs during the synthetic processes. These observations are consistent with the XRD results. The energy-dispersive X-ray spectrum (EDX) result further confirms the existence of N and Pd in the Pd/N-MSC-30-two175 (Figure S5). The content of Pd and N, measured by inductively coupled plasma optical emission spectroscopy (ICPOES) analysis and elemental analysis, is 4.0 wt% and 5.72 wt%, respectively (Table S1 and S2). The catalytic performance of the prepared catalysts for dehydrogenation of FA was evaluated. The amount of gases released during the reaction was measured on the basis of volu-
ACS Paragon Plus Environment
Page 3 of 6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
ACS Catalysis
metric measurement. Remarkably, the as-prepared Pd/NMSC-30 serves as an efficient catalyst for selective dehydrogenation of FA to H2 with complete conversion. The best catalytic activity was observed for Pd/N-MSC-30-two-175 catalyst, in which the reaction was completed in 0.35 min generating 144 mL of gas (H2 + CO2) from an aqueous FA-SF (sodium formate) system (nFA:nSF = 1:2.5, nPd/nFA = 0.02). At 333 K we determined a turnover frequency (TOF) of 8414 h-1 taking into consideration the total metal amount employed in the reaction (Figure 2 and S6), which, to our knowledge, is the highest TOF reported for the 100% dehydrogenation of FA to H2 with a heterogeneous catalyst under similar conditions (Table S3). Clearly, the TOF of Pd/N-MSC-one (5408 h-1) at 333 K is much lower than that of Pd/N-MSC-30-two-175, demonstrating that a better dispersity of Pd NCs and a higher content of N in the Pd/N-MSC-30-two-175 catalyst have been achieved via the tandem approach, in agreement with the results of XRD, HAADF-STEM, and elemental analysis. The excess volumes of gas, over the theoretical value of 144 mL (H2 + CO2) from FA decomposition, can be attributed to the decomposition of SF in this system (Figure S7). The H2 generation rate of 32 liters H2 min-1 gPd-1, corresponding to a theoretical power density of 43 W min-1 gPd-1, is comparable with other reported values using FA-SF systems.6f The exclusive formation of H2 and CO2 without detectable CO impurity (< 5 ppm) was confirmed by gas chromatography (GC) analyses (Figure S8 and S9), implying excellent selectivity, which is crucial for fuel cell applications. The time-dependent H2 generation at different temperatures in the presence of Pd/NMSC-30-two-175 and FA-SF were recorded (Figure S10a). At temperatures of 323, 313, and 303 K complete conversion was observed in 0.50, 0.88, and 1.63 min, respectively, corresponding to TOFs of 5890, 3334, and 1803 h-1. An Arrhenius plot of the natural log TOF versus 1/T (Figure S10b) yields an activation energy (Ea) of 43.7 kJ mol-1. This is comparable to other state-of-the-art heterogeneous catalyst systems for FA decomposition reported previously (Table S3), indicating that the Pd/N-MSC-30-two-175 catalyst is effect for the rapid and selective conversion of FA into a CO-free H2-containing stream at moderate temperature. In addition, the concentration of SF in the dehydrogenation of FA was investigated. As shown in Figure S11, different ratios of FA and SF were modulated for the dehydrogenation of FA over the Pd/N-MSC-30two-175 catalyst. It was found that the activities of FA decomposition improved with increasing
Figure 2. Volume of the released gas (H2 + CO2) versus time for the dehydrogenation of FA-SF solution at 333 K over different catalysts: (1) Pd/MSC-30, (2) Pd/N-MSC-one, and (3) Pd/NMSC-30-two-175 (nFA:nSF = 1:2.5; FA, 3 mmol; nPd/nFA= 0.02). Inset: Corresponding TOF values of the dehydrogenation of FA over the catalysts.
molar percentage of SF in the FA-SF solution until the ratio of FA and SF reached 1:2.5. After that, further increasing the SF percentage had no additional positive effect on the FA decomposition. Durability/recyclability of a catalyst is critical for practical applications. To test the durability of Pd/N-MSC-30-two-175, the catalyst was recollected and washed after the completion of a FA decomposition experiment for 5 subsequent cycles. As shown in Figure S12a, the activity remained little changed, suggesting the good durability of this catalyst. Moreover, to further investigate the tolerance of the catalyst, after 5 cycles, the catalyst was employed to catalytic dehydrogenation of different amounts of FA (firstly 9 mmol FA, giving a Pd/FA mole ratio of 0.0067 for 5 cycles; and then 3 mmol FA, giving a Pd/FA mole ratio of 0.02 for another 5 cycles). It was found that even after total 15 cycles, the catalytic activity is maintained (Figures S12b and S12c), corresponding to a total turnover number (TON) of 1250. The catalytic performance of the dehydrogenation of FA over the Pd/N-MSC-30-two-175 catalyst with different nPd/nFA ratios was evaluated (Figure S13). At low nPd/nFA ratios, slight decrease of TON was observed. It is notably that the catalytic performance is not directly proportional to the nitrogen content in the MSC-30 (Figure 2, S6 and Table S2). To gain more information about the influence factors of the catalytic performances beyond nitrogen content, surface areas and pore structures of the prepared samples were evaluated by N2 sorption measurements. As shown in Figure 3a and Table S4, the calculated Brunauer-EmmettTeller (BET) surface areas of MSC-30, N-MSC-30-two-175 (treated with NaOH/NaBH4, 30 mg NaBH4 in 1 mL 2 M NaOH), Pd/MSC-30, and Pd/N-MSC-30-two-175 are 3221, 3282, 2217, and 2012 m2 g-1, respectively. The appreciable decrease in BET surface area of ∼1270 m2 g-1 for the Pd/NMSC-30-two-175 sample as compared to the N-MSC-30-two175 (treated with NaOH/NaBH4) support indicates that the Pd NCs have been successfully dispersed inside the pores of NMSC-30-two-175, which is also accompanied by a distinct decease of pore volume (Table S4) and slight decrease of pore size (Figure S14). It is worth noting that the addition of NaOH/NaBH4 during the synthetic process of the catalysts plays an important role in enlargement of the BET surface area of the N-functionalized MSC-30 support. As shown in Figure S15, the BET surface area of fresh prepared N-MSC-30-two175 is about 1365 m2 g-1, in sharp contrast, the value increases to 3282 m2 g-1 after treatment with NaOH/NaBH4. This phenomenon can be found in all other N-MSC-30 samples (Figure S16, S17 and Table S4). In comparison with untreated samples, the samples treated with NaOH/NaBH4 exhibit much higher BET surface areas, which might be attributed to the removal of the bulk thermolysis products of urea, such as cyanuric acid, ammelide and ammeline,10 in alkaline solutions. Comparison of the properties of the different catalysts and supports suggest that both the N content and the specific surface area result in the enhancement of catalytic performance for FA dehydrogenation. The nitrogen-containing groups sufficiently anchor the NCs preventing aggregation and overgrowth during the synthetic and catalytic processes, consistent with the greater affinity of supports for Pd precursors/seeds.3b,6f,7d The nitrogen-containing group in the catalyst can serve as base sites, benefiting the deprotonation of FA to form a Pd-formate (Pd-HCOO-) intermediate and a proton (H+). Subsequently, the formed Pd-formate species undergo C-H
ACS Paragon Plus Environment
ACS Catalysis
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
bond dissociation to produce CO2 and a Pd-hydride (Pd-H-) species, which reacts with proton to afford H2.7d Meanwhile, the high specific surface area provides the spatial confinement effect, induced by the pores of supports, which largely prevent Pd NCs from aggregation. As a result, homogeneously dispersed Pd NCs have been successfully immobilized in the supports prepared by the tandem process, which is of great benefit to achieve high accessibility catalytic sites and then obtain high catalytic activity. To gain additional insight into the high activity of Pd/NMSC-30-two-175 catalyst, the recycled catalyst recovered after the durability tests at 333 K was characterized in detail by XRD, XPS, and STEM. The XRD measurement reveals that the crystalline structure of the Pd NCs is preserved and no noticeable diffraction peaks from Pd are detected (Figure 3b). The stability of this catalyst was further confirmed by the XPS analyses. As shown in Figures 3c, the electronic states of N 1s and Pd 3d are retained. Notably, the recycled Pd/N-MSC-30two-175 shows a similar particle size distribution as was observed before the catalytic reaction (Figures 3d-3f), indicating the as-prepared catalyst possesses excellent durability/recyclability during FA decomposition.
Figure 3. (a) N2 sorption isotherms of the as-prepared samples at 77 K (Note: N-MSC-30-two-175 was treated with NaOH/NaBH4), (b) XRD pattern and (c) N 1s and Pd 3d XPS spectra of the recycled Pd/N-MSC-30-two-175 catalyst, (d and e) HAADF-STEM images and (f) corresponding size distribution of Pd NCs of recycled Pd/N-MSC-30-two-175 catalyst.
In summary, a tandem heat-treatment method has been developed to prepare N-functionalized porous carbon materials, which proved to be a more effective strategy to generate robust N-functional groups than the one-step process. Highlydispersed Pd NCs immobilized by this N-MSC-30 have been successfully synthesized by a facile wet chemical impregnation and reduction method. Given the ultra-small size, high specific surface area, and the synergistic effect between the Ncontaining groups in the supports and the Pd NCs, the resultant catalyst offers much higher activity than Pd/N-MSC-30one toward efficient CO-free H2 generation for the complete decomposition of FA in a FA-SF system under mild conditions. Notably, the as-synthesized catalyst exhibits excellent cycling stability during FA decomposition due to the confinement of Pd NCs within the pores of the N-MSC-30 supports. The excellent catalytic activity and recyclability, as well as the convenient approach to generate ultra-small metal clusters make it an ideal catalyst in terms of potential practical application for hydrogen storage using FA as an efficient carrier.
ASSOCIATED CONTENT
Page 4 of 6
AUTHOR INFORMATION Corresponding Author *
[email protected] Notes The authors declare no competing financial interests. Supporting Information. The Supporting Information is available free of charge on the ACS Publications website. Experimental details, structural characterizations and catalytic performances of the catalysts, Figures S1-S17, and Tables S1-S4.
ACKNOWLEDGMENT The authors thank the reviewers for valuable suggestions. This research was supported by the International Joint Research Program for Innovative Energy Technology of the Ministry of Economy, Trade, and Industry (METI). A part of this work was conducted in Nagoya Institute of Technology, supported by Nanotechnology Platform Program (Molecule and Material Synthesis) of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan.
REFERENCES (1) (a) Mori, K.; Hara, T.; Mizugaki, T.; Ebitani, K.; Kaneda, K. J. Am. Chem. Soc. 2004, 126, 10657-10666. (b) Yin, H.; Tang, H. J.; Wang, D.; Gao, Y.; Tang, Z. Y. ACS Nano 2012, 6, 8288-8297. (c) Li, G.; Jin, R. Acc. Chem. Res. 2013, 46, 1749-1758. (2) (a) Aijaz, A.; Karkamkar, A.; Choi, Y. J.; Tsumori, N.; Rönnebro, E.; Autrey, T.; Shioyama, H.; Xu, Q. J. Am. Chem. Soc. 2012, 134, 13926-13929. (b) Guo, Z.; Xiao, C.; Maligal-Ganesh, R. V.; Zhou, L.; Goh, T. W.; Li, X.; Tesfagaber, D.; Thiel, A.; Huang, W. ACS Catal. 2014, 4, 1340-1348. (c) Fujiwara, K.; Müller, U.; Pratsinis, S. E. ACS Catal. 2016, 6, 1887-1893. (3) (a) Li, Z.; Li, J.; Liu, J.; Zhao, Z.; Xia, C.; Li, F. ChemCatChem 2014, 6, 1333-1339. (b) Wang, F.; Xu, J.; Shao, X.; Su, X.; Huang, Y.; Zhang, T. ChemSusChem 2016, 9, 246-251. (c) Chen, Y.-Z.; Cai, G.; Wang, Y.; Xu, Q.; Yu, S.-H.; Jiang, H.-L. Green Chem. 2016, 18, 1212-1217. (d) He, L.; Weniger, F.; Neumann, H.; Beller M. Angew. Chem., Int. Ed. 2016, 55, 12582-12594. (4) (a) Schlapbach, L.; Züttel, A. Nature 2001, 414, 353-358. (b) Graetz, J. Chem. Soc. Rev. 2009, 38, 73-82. (c) Hamilton, C. W.; Baker, R. T.; Staubitz, A.; Manners, I. Chem. Soc. Rev. 2009, 38, 279293. (d) Murray, L. J.; Dincă, M.; Long, J. R. Chem. Soc. Rev. 2009, 38, 1294-1314. (e) Eberle, U.; Felderhoff, M.; Schüth, F. Angew. Chem., Int. Ed. 2009, 48, 6608-6630. (f) Kim, S.-K.; Han, W.-S.; Kim, T.-J.; Kim, T.-Y.; Nam, S.-W.; Mitoraj, M.; Piekoś, L.; Michalak, A.; Hwang, S.-J.; Kang, S. O. J. Am. Chem. Soc. 2010, 132, 9954-9955. (g) Neiner, D.; Karkamkar, A.; Bowden, M.; Choi, Y. J.; Luedtke, A.; Holladay, J.; Fisher, A.; Szymczak, N.; Autrey, T. Energy Environ. Sci. 2011, 4, 4187-4193. (h) Chen, H. M.; Chen, C. K.; Liu, R.-S.; Zhang, L.; Zhang, J.; Wilkinson, D. P. Chem. Soc. Rev. 2012, 41, 5654-5671. (5) (a) Fellay, C.; Dyson, P. J.; Laurenczy, G. Angew. Chem., Int. Ed. 2008, 47, 3966-3968. (b) Johnson, T. C.; Morris, D. J.; Wills, M. Chem. Soc. Rev. 2010, 39, 81-88. (c) Boddien, A.; Mellmann, D.; Gärtner, F.; Jackstell, R.; Junge, H.; Dyson, P. J.; Laurenczy, G.; Ludwig, R.; Beller, M. Science 2011, 333, 1733-1736. (d) Grasemann, M.; Laurenczy, G. Energy Environ. Sci. 2012, 5, 8171-8181. (e) Moret, S.; Dyson, P. J.; Laurenczy, G. Nat. Commun. 2014, 5, 4017. (f) Mellmann, D.; Sponholz, P.; Junge, H.; Beller, M. Chem. Soc. Rev. 2016, 45, 3954-3988. (g) Sordakis, K.; Tsurusaki, A.; Iguchi, M.; Kawanami, H.; Himeda, Y.; Laurenczy, G. Chem. Eur. J. 2016, 22, 15605-15608. (6) (a) Ojeda, M.; Iglesia, E. Angew. Chem., Int. Ed. 2009, 48, 4800-4803. (b) Gu, X.; Lu, Z.-H.; Jiang, H.-L.; Akita, T.; Xu, Q. J. Am. Chem. Soc. 2011, 133, 11822-11825. (c) Bi, Q.-Y.; Du, X.-L.; Liu, Y.-M.; Cao, Y.; He, H.-Y.; Fan, K.-N. J. Am. Chem. Soc. 2012, 134, 8926-8933. (d) Zhu, Q.-L.; Tsumori, N.; Xu, Q. Chem. Sci. 2014, 5, 195. (e) Yang, X.; Pachfule, P.; Chen, Y.; Tsumori, N.; Xu, Q. Chem. Commun. 2016, 52, 4171-4174. (f) Wang, N.; Sun, Q.; Bai, R.;
ACS Paragon Plus Environment
Page 5 of 6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
ACS Catalysis
Li, X.; Guo, G.; Yu, J. J. Am. Chem. Soc. 2016, 138, 7484-7487. (g) Bi, Q.-Y.; Lin, J.-D.; Liu, Y.-M.; He, H.-Y.; Huang, F.-Q.; Cao, Y. Angew. Chem., Int. Ed. 2016, 55, 11849-11853. (h) Bi, Q.-Y.; Lin, J.D.; Liu, Y.-M.; He, H.-Y.; Huang, F.-Q.; Cao, Y. J. Power Sources 2016, 328, 463-471. (7) (a) Tedsree, K.; Li, T.; Jones, S.; Chan, C. W. A.; Yu, K. M. K.; Bagot, P. A. J.; Marquis, E. A.; Smith, G. D. W.; Tsang, S. C. E. Nat. Nanotechnol. 2011, 6, 302-307. (b) Jiang, K.; Xu, K.; Zou, S.; Cai, W.-B. J. Am. Chem. Soc. 2014, 136, 4861-4864. (c) Chen, Y.; Zhu, Q.-L.; Tsumori, N.; Xu, Q. J. Am. Chem. Soc. 2015, 137, 106-109. (d) Song, F.-Z.; Zhu, Q.-L.; Tsumori, N.; Xu, Q. ACS Catal. 2015, 5, 5141-5144. (e) Zhu, Q.-L.; Tsumori, N.; Xu, Q. J. Am. Chem. Soc. 2015, 137, 11743-11748. (8) (a) Li, P.-Z.; Aijaz, A.; Xu, Q. Angew. Chem., Int. Ed. 2012, 51, 6753-6756. (b) Jeon, S.-I.; Park, H.-R.; Yeo, J.-G.; Yang, S.; Cho, C. H.; Han, M. H.; Kim, D. K. Energy Environ. Sci. 2013, 6, 1471-1475. (9) Liu, B.; Yao, H.; Song, W.; Jin, L.; Mosa, I. M.; Rusling, J. F.; Suib, S. L.; He, J. J. Am. Chem. Soc. 2016, 138, 4718-4721. (10) (a) Bann, B.; Miller, S. A. Chem. Rev. 1958, 58, 131-172. (b) Schaber, P. M.; Colson, J.; Higgins, S.; Thielen, D.; Anspach, B.; Brauer, J. Thermochim. Acta 2004, 424, 131-142.
ACS Paragon Plus Environment
ACS Catalysis
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 ACS Paragon Plus Environment
Page 6 of 6
6
