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Gold catalysis and photoactivation: a fast and selective procedure for the oxidation of free sugars Mehdi Omri, Frédéric Sauvage, Yan Busby, Matthieu Becuwe, Gwladys Pourceau, and Anne Wadouachi ACS Catal., Just Accepted Manuscript • DOI: 10.1021/acscatal.7b03394 • Publication Date (Web): 19 Jan 2018 Downloaded from http://pubs.acs.org on January 19, 2018
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ACS Catalysis
Gold catalysis and photoactivation: a fast and selective procedure for the oxidation of free sugars Mehdi Omri,1 Frédéric Sauvage,2 Yan Busby,3 Matthieu Becuwe,2 Gwladys Pourceau,*,1 and Anne Wadouachi1 1 Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources (LG2A) UMR CNRS 7378 - Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 rue Saint Leu, FR-80039 Amiens Cedex, France. 2 Laboratoire de Réactivité et Chimie des Solides (LRCS), UMR CNRS 7314 - Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 rue Saint Leu, FR-80039 Amiens Cedex, France. 3 Laboratoire Interdisciplinaire de Spectroscopie Electronique (LISE), Namur Institute of Structured Matter (NISM), University of Namur, 61 Rue de Bruxelles, 5000 Namur, Belgium. KEYWORDS: carbohydrates, photocatalytic oxidation, gold catalysis, aldonates, oligosaccharides modification
ABSTRACT: A fast and efficient methodology for the selective oxidation of sugars into corresponding sodium aldonates is herein reported. Hydrogen peroxide was used as a cheap oxidant and electron scavenger, in the presence of only 0.0030.006 mol % of gold in basic conditions. Three photocatalysts were studied, namely Au/Al2O3, Au/TiO2 and Au/CeO2, the latter being the most efficient (TOF > 750 000 h-1) and perfectly selective. Only 10 minutes exposition under standard incident sunlight irradiation (A.M.1.5G conditions - 100 mW/cm2) affords total conversion of glucose into the corresponding sodium gluconate. Demonstrating its versatility, this methodology was successfully applied to a variety of oligosaccharides leading to the corresponding aldonates in quantitative yield and high purity (>95%) without any purification step. The photocatalyst was recovered by simple filtration and re-used 5 times leading to the same conversion and selectivity after 10 min of illumination. KEYWORDS: carbohydrates, photocatalytic oxidation, gold catalysis, aldonates, oligosaccharides modification
The use of sugars as renewable and abundant feedstock and their eco-friendly conversion into chemicals are becoming increasingly attractive to synthesize high-valueadded products.1 Sugars are polyfunctional and serve as a chemical platform to synthesize a wide variety of derivative compounds after chemical modifications.2 However, the multi-step protocols and hazardous chemicals used for these transformations penalize this chemistry to be transposed to the industrial scale. Among the different "glycotransformations", C1-oxidation is of particular interest since it leads to aldonic acids or their salts, widely used in cosmetics, pharmaceutical, food and paper industries.3 Conventional procedures gather several drawbacks such as limited selectivity to aldonic acids, production of degradation by-products owing to the weakness of the interglycosidic bond, separation issues of the products, or environmental toxicity. In this context, heterogeneous photocatalytic transformation is considered as one of the most promising sustainable and eco-friendly procedure. Although many efforts were devoted to design semiconducting (SC) materials exhibiting a high photocatalytic yield and selective charge transfer processes under visible light exposure rather than the lower UV flux of photons, the most promising photocatalyst materials developed so
far are suffering from low oxidative selectivity and restricted spectral absorption into the UV owing to a too large bandgap value.4-6 This is for instance the case of the benchmark anatase TiO2 semi-conductor for which its 3.20 eV bandgap value restricts the light absorption/conversion below 410 nm, thus representing at best only 5 % of the total solar spectrum. Among other approaches such as aliovalent doping, the use of SCsupported metal nanoparticles, especially gold or silver, was rapidly highlighted as an efficient approach to address this issue by extending the spectral absorption to the visible region thanks to localized surface plasmon resonance (LSPR) effect. In addition, it also affords to prolong electron/hole charge separation in the metal owing to the interfacial metal/SC Schottky barrier assisting the electron injection into the conduction band of the SC.7-12 Some studies on the selective photo-oxidation of organic compounds such as thiol into disulfide,13 aliphatic alcohol into carbonyl derivative14 or aminobenzyl alcohol into aminobenzaldehyde15 were recently reported in the presence of catalyst Au/MOx (MOx: metal oxide).13-17 On the other hand, only a few studies aimed at selectively photo-oxidizing carbohydrates using TiO2, Ag/TiO2 or Cr/TiO2 with limited success.18-21 Indeed, the results sys-
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ACS Catalysis tematically report a low conversion yield and a lack of selectivity to the corresponding gluconic acid, leading to smaller chain monosaccharides and partial- and overoxidized byproducts. Interestingly, Zhou et al. reported very recently the aerobic oxidation of two monosaccharides (glucose and xylose) at micromolar scale in 4 hours at 30°C under high light power (300 mW/cm2) into the corresponding acids with good selectivity by using Au/TiO2 photocatalyst (3.8 mol %).22 In this work, we report on a simple and an efficient procedure affording a fast and selective photoelectrochemical reaction leading to pure sodium mono- and oligo-aldonates in less than 10 minutes of incident light exposure under standard photovoltaic A.M.1.5G conditions (100 mW/cm2) at room temperature (Scheme 1).
O
Au/MOx 1.1 eq H2O2 1 eq NaOH
HO
hν
OH R
O HO
OH
OH
OH ONa
HO R
O
OH
O
R= H, mono- or oligo-saccharides
values reported in the literature for oxidation using atmospheric air (7-16% in most cases).18-21 Surprisingly, Au/TiO2 exhibited the lower photocatalytic activity in terms of both conversion and selectivity, albeit still superior than values reported in the literature: 78% of glucose were transformed into corresponding sodium gluconate with a selectivity of ~85% in 30 minutes. Au/Al2O3 enables evaluating the intrinsic photo-catalytic properties of gold itself since the 4.4 eV bandgap value of Al2O3 prevents any electron injection from Au to Al2O3 and any direct bandgap excitation. Although one would have expected this catalyst lagging far behind, light absorption by gold ensures a quantitative conversion into pure sodium gluconate with a selectivity greater than 95% in 30 minutes. Supporting gold to nanocrystalline CeO2 accelerates significantly glucose oxidation without penalizing the selectivity (Fig. 1). Quantitative conversion to the gluconate was obtained in only 10 minutes of illumination. A turnover frequency (TOF) of 752 380 h-1 was calculated for this photocatalyst after 5 min of irradiation (i.e. at 79% conversion).
Scheme 1. Photocatalyzed oxidation of saccharides into corresponding aldonates.
The photocatalysts performance was evaluated in water for the oxidation of glucose using a catalytic charge of 0.003-0.006 mol % of gold (i.e. a substrate/gold ratio between 15 000 and 30 000), 1.1 eq of hydrogen peroxide as an electron scavenger and 1 eq of sodium hydroxide. After filtration of the catalyst, the resulting reaction media was freeze-dried and analyzed by NMR and HPLC to evaluate both conversion and selectivity into sodium gluconate (Fig. S5-S6). Otherwise, EDX analysis of lyophilized media did not evidence any dissolution of the photocatalyst (Fig. S7). As shown in figure 1, whatever the photocatalyst, moderate to high conversion yields (between 30 and 79%) into gluconate were already achieved in only 5 minutes of illumination (Fig. S8). This is significantly higher than the
Conversion (%)
In this study, three different photocatalysts are investigated: Au/TiO2 and Au/CeO2 for which hot electrons from gold excited state can be injected into the related conduction band of the SC, and Au/Al2O3 for which the excessive value of the bandgap (≈ 4.4 eV) prevents any interfacial charge transfer to proceed.23 The photocatalysts were prepared by a deposition−precipitation method and characterized by transmission electron microscopy (TEM), flame spectrometry (AAS) and X-ray diffraction (XRD).24 The gold nanoparticles have a size of around 2-3 nm with good monodispersity (Fig. S1). Gold loading of each catalyst is between 0.4-0.7 wt % (Table S1) and no change of crystallinity of the SC support was noticed subsequently to gold deposition (Fig. S2). Gold nanoparticles show a broad plasmonic absorption band at ca. 550 nm as measured in UV-visible absorption spectroscopy in reflectance mode (Fig. S3). The XPS analysis on SC supported gold nanoparticles shows that gold is mainly found in the metallic state (Au0 represent 85% of the peak area in Au/CeO2 while Au+I oxidation state 15%, Fig. S4).
100 80 60 40 20 0 0
10 20 Time (min)
30
100 Selectivty (%)
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80 60 40 20 0 5
10 20 Time (min)
30
Figure 1. Top: Conversion of glucose vs time using Au/Al2O3 (green line), Au/TiO2 (red line) or Au/CeO2 (blue line) catalysts; bottom: Selectivity toward sodium gluconate using Au/Al2O3 (green bar), Au/TiO2 (red bar) or Au/CeO2 (blue bar) catalysts
Although the bandgap value of TiO2 and CeO2 are relatively comparable, the differences between TiO2 and CeO2-supported gold photocatalysts can be explained by three factors: 10,14,25 (i) LSPR effect is stronger for Au/CeO2 than for Au/TiO2; this enables a better light capture by
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ACS Catalysis the gold nanoparticles (ii) the conduction band position of CeO2 is more oxidizing than TiO2 counterpart and the Schottky barrier is lower for CeO2 (0.8 eV) than in TiO2 (1.09 eV), thus one could anticipate that gold excited states should inject faster in CeO2 than in TiO2 which for this latter already takes place in less than 240 fs (more efficient charge separation) and (iii) a strong quenching of CeO2 luminescence has been observed under UV excitation (375 nm) when supporting Au NPs suggesting either a reduction of recombination rate or also electron injection into the metal gold, thus offering more separated carriers to onset the photo-oxidation process. In addition, the oxygen vacancies at the CeO2 surface help to achieve a better gold dispersion at the surface of the semiconductor as well as to enhance the stability of gold nanoparticles. The lower selectivity of TiO2-based photocatalysts has been previously pointed out.22 It has been endowed to the formation of strong oxidizing radicals formed from the direct hole transfer from the O 2p orbitals of TiO2 under UV irradiation. A very recent work showed that glucose can be converted into formate using nano-TiO2 in basic conditions as a result from the formation of two types of strongly oxidative radicals ·OH (E° = +2.38 V vs. NHE) and O2·- (+1,72 V vs. NHE) when in presence of hydroxyl ions.26 Several blank tests were carried out to better highlight the role of the photocatalyst (Table 1). Firstly, a reaction without any photocatalyst was performed under A.M.1.5G illumination showing no reaction as one would have expected (entry 1). Secondly, the properties of the semiconducting materials alone (without gold nanoparticles) were evaluated according to the same reaction conditions (entries 2-4). In all cases, whatever the nature of the metal oxide, glucose remained unchanged, thus confirming that gold-free semi-conductors are not photocatalysts under A.M.1.5G white light, proving the photochemical stability of these latter together with stressing the need to combine synergistically the SC with the Au NPs to achieve an efficient and selective photon-induced oxidation reaction. This gives evidence that OH. formed subsequently to hole transfer from the SC valence band cannot oxidize the glucose in our conditions, therefore is not an intermediate involved in the glucose to gluconate conversion, at least under AM1.5G conditions. Finally, similar reactions were performed in darkness. In this case, whatever the catalyst, glucose remained unchanged (entries 7, 10, 16) confirming that glucose is chemically stable in our conditions and underlying that the oxidation reaction involves photon-induced charge transfer processes. Indeed, no glucose decomposition in presence of hydrogen peroxide is herein observed (entries 1-4, 7, 10, 16, Table 1), by contrast to what has been experienced by Comotti et al. using various mixture between glucose and hydrogen peroxide at pH = 9.5 without catalyst and in darkness.27 The role of hydrogen peroxide is crucial: even in presence of gold catalyst (entries 6, 9, 13), neither oxidation nor degradation of glucose was observed if hydrogen peroxide was not added. This is in contrast to several works in the literature reporting the use of atmospheric
air as oxidant for the oxidation of carbohydrates.7,8 This discrepancy may stem from the shorter reaction time (< 30 minutes) and the lower amount of gold lying between 0.003-0.006 mol % in our study, whereas several hours in presence of 1000 times more catalyst were reported in literature.22 Although more investigations are underway by electron spin resonance and transient absorption and emission spectroscopies to better insight on the nature of the intermediate species which are formed at Au/SC surface responsible for the sugar oxidation, for which the results will be reported elsewhere, we argue that in our case H2O2 plays the role of electron scavenger after gold has injected electron into the conduction band of the SC. This electron scavenging affords enhancing the charge separation lifetime in agreement with previous observations in the literature to avoid unwished fast radiative recombination processes.28-29 This electron transfer leads to ·OH oxidant radicals and HO- formation.30 Interestingly, it is well-established that 1 mole of hydrogen peroxide can be reformed after reaction of 2 moles of ·OH.31 This is fully consistent with our results showing that 75 % of glucose is converted with only 0.5 eq of H2O2 (entry 12). Table 1. Influence of some parameters on the conversion of glucose and on the selectivity towards gluconic acid Catalyst
neq H2O2
neq NaOH
Conversion (%)
Selectivity (%)
1
-
1.1
1
0
-
2
TiO2
1.1
1
0
-
3
Al2O3
1.1
1
0
-
4
CeO2
1.1
1
0
-
1.1
1
49
95
0
1
0
-
b
5 6
Au/TiO2
b
7
1.1
8 9
Au/Al2O3
b
10
b
1.1
b
1
0
-
11
1.1
1
>99
>95
12
0.5
1
75
>95
0
1
0
-
1.1
0.5
13 14
Au/CeO2
a
0
b
1
15
1.1
16
1.1
b
63
>95
a
>95
a
29
b
0
b
-
a
b
Reaction conditions: glucose 250 mg, catalyst 2.5 mg, 2 water 5 mL, light power 100 mW/cm (A.M.1.5G), 10 min. [a] reaction time extended to 1 hr, [b] reaction performed in darkness.
On the other hand, when reducing the quantity of NaOH to 0.5 eq, the conversion yield decreased to 63 % in 10 min and to 29 % only without any base after 1 hour (entries 14-15). We hypothesized that the base plays three
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roles: (i) free of base, the surface of the gold catalyst can be poisoned by the gluconic acid produced (ii) mineral bases inhibit the strong oxidative species generated under UV light (hydroxyl radicals and singlet oxygen), and promote visible-light-induced oxidation as recently pointed out by Zhou et al.22 and (iii) in addition to the locally produced OH- from hydrogen peroxide reduction, the base accelerates the hydration of aldehyde into geminal diol, which adsorbs to the Au/SC surface to form a metal alkoxide, and facilitates the β-hydride elimination by hole transfer from gold excited state leading to the formation of the corresponding carboxylate.32-33
mono- to oligosaccharides (degree of polymerisation (DP) from 1 to 6) leading to the corresponding mono to hexaaldonates with excellent conversion and selectivity (Table 3, Fig. S9-S10). Interestingly, by contrast to the microwave-assisted procedure recently described,24 NaOH can be used as a base even for oligosaccharides without degradation and/or hydrolysis of the interglycosidic bond, probably thanks to the mild conditions (room temperature and short reaction time). Moreover, this photoelectrochemical reaction is not substrate-dependent: lactose, maltose or cellobiose (entries 2-4), which exhibits different types of glycosidic linkage (α or β) and of glycosidic residues (glucose or galactose) reacted quantitatively in 10 minutes with a selectivity greater than 95 %.This methodology was also successfully applied to higher DP oligosaccharides such as maltotriose and maltohexose (entries 5-6) demonstrating its versatility. This appealing result underlines once again the advantage of photochemistry against, for instance, microwave-assisted procedure in terms of substrate-dependency. We thus demonstrate systematically fast, quantitative conversion yield and excellent selectivity regardless of the type of sugar, leading to pure aldonates without any means of purification step.
The photocatalyst was retrieved and re-used 5 times and led to the same excellent conversion (>99%) and selectivity (>95%) after 10 min of irradiation. Post-ageing characterization by means of TEM and AAS showed no structural, chemical and textural transformation of the photocatalyst upon cycling (Table 2, Fig. S1, Table S1). No further oxidation of gold was also evidenced by XPS (Fig. S4). This stresses its high robustness in the different media herein investigated. Nevertheless, a decrease in the TOF value was observed: a TOF of 466 000 h-1, still higher than those reported in literature, was calculated for the sixth run after 5 min of irradiation (Fig. S8).
In conclusion, a mild, very fast and versatile method to selectively produce aldonates from mono and oligosaccharides derived from biomass was successfully developed. This reaction is performed in water, using a cheap and green oxidant and involving a very few quantities of a reusable catalyst. The photocatalytic results herein reported were gathered using a class A calibrated standard A.M.1.5G light source (P = 100 mW/cm2) typically used for photovoltaic characterization; ie. a procedure reproducible and realistic with respect to the end-application. These first results call for further development of novel oligoaldonate derivatives in large and green scale for their utilization as detergents, pharmaceuticals or cosmetics to replace petroleum-based chemicals.
Table 2. Characteristics of Au/CeO2 after 5 runs a
b
Catalyst
Mean size (nm)
Gold content (%)
initial
2.9 ± 0.7
0.50 ± 0.01
after 5 runs
3.2 ± 0.6
0.49± 0.01
[a] Mean size was determined by TEM, [b] gold content was determined by AAS
Such excellent results can be obtained also at 3g-scale keeping same conversion yield and selectivity into sodium gluconate. Finally, the optimized conditions (Table 1, entry 11) were successfully applied to a variety of saccharides from Table 3. Photocatalyzed oxidation of various substrates. Sugar
Product OH
D-Glucose OH
1
OH
OH
HO HO
OH
>95
>99
>95
ONa
O HO
O O OH
O OH O HO
>99
O
HO
OH
HO
Select.(%)
OH
D-Maltose
HO HO
ONa OH
Conv. (%)
OH
HO O
HO HO
2
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OH
O
OH
OH
HO
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ACS Catalysis
3
ONa
HO OH
D-Lactose
HO O OH
OH O
HO
O O
HO
HO O H
OH
O O HO
HO
OH
O HO
>95
>99
>95
O O OH
O
HO
>99
HO
OH
OH
HO HO
>95
ONa
OH HO HO
O
>99
HO
O OH
>95
OH
OH
D-Cellobiose
4
>99
OH
OH
HO
OH
OH
D-Maltotriose
O
HO HO
OH OH O HO
OH
5
H
O OH O
O
O HO
OH HO
ONa HO O OH
2 O HO
O OH
OH
OH
HO OH HO HO
D-Maltohexose
O OH OH O HO
O OH OH O HO
6
OH H
OH HO
5 O HO
OH O OH OH O HO
O O HO
O OH O HO
O
ONa HO O
OH O
O OH
OH
OH OH
HO
10
Reaction conditions: sugar 250 mg, Au catalyst 2.5 mg, NaOH 1 eq, H2O2 1.1 eq, water 5 mL, hν (standard A.M.1.5G conditions), min. Conversion rates (conv.) and selectivity (selec.) were determined by NMR
ASSOCIATED CONTENT Supporting Information. This material is available free of charge via the Internet at http://pubs.acs.org. Experimental details, materials, methods, comparison experiments, catalysts and crude characterization.
AUTHOR INFORMATION Corresponding Author * E-mail:
[email protected] Notes The authors declare no competing financial interest
ACKNOWLEDGMENT M. O., M. B., G. P. and A. W wish to thank the Conseil Régional de Picardie for its financial support. F.S. wish to thank the french national research agency ANR for funding Photo2batt project.
REFERENCES (1) Gallezot, P. Chem. Soc. Rev. 2012, 41, 1538-1558. (2) Chatterjee, C.; Pong, F.; Sen, A. Green Chem. 2015, 17, 40-71.
(3) Hustede, H.; Haberstroh, H. J.; Schinzig, E. in Ullmann's Encyclopedia of Industrial Chemistry, 6th ed, Wiley-VCH, Weinheim, 2000, p 449. (4) Park, H.; Kim, H. I.; Moon, G. H.; Choi, W. Energy Environ. Sci. 2016, 9, 411-433 (5) Yurdakal, S.; Palmisano, G.; Loddo, V.; Augugliaro, V.; Palmisano, L. J. Am. Chem. Soc. 2008, 130, 1568-1569 (6) Augugliaro, V.; Caronna, T.; Loddo, V.; Marc, G.; Palmisano, G.; Palmisano, L.; Yurdakal, S. Chem. Eur. J. 2008, 14, 4640- 4646 (7) Wang, C.; Astruc, D. Chem. Soc. Rev. 2014, 43, 7188-7216 (8) Primo, A.; Corma, A.; Garcia, H. Phys. Chem. Chem. Phys. 2011, 13, 886-910 (9) Kominami, H.; Tanaka, A.; Hashimoto, K. Appl. Catal. A 2011, 397, 121-126 (10) Furube, A.; Du, L.; Hara, K.; Katoh, R.; Tachiya, M. J. Am. Chem. Soc. 2007, 129, 14852-14853 (11) Tian, Y.; Tatsuma, T. J. Am. Chem. Soc. 2005, 127, 76327637 (12) Xiao, M. D.; Jiang, R. B.; Wang, F.; Fang, C. H.; Wang, J. F.; Yu, J. C. J. Mater. Chem. A 2013, 1, 5790−5805 (13) Naya, S.-I.; Teranishi, M.; Kimura, K.; Tada, H. Chem. Commun. 2011, 47, 3230-3232 (14) Naya, S.-I.; Teranishi, M.; Isobe, T.; Tada, H. Chem. Commun. 2010, 46, 815-817
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(15) Kowalska, E.; Prieto Mahaney, O. O.; Abe, R.; Ohtani, B. Phys. Chem. Chem. Phys. 2010, 12, 2344-2355 (16) Kowalska, E.; Abe, R.; Ohtani, B. Chem. Commun. 2009, 241-243 (17) Tanaka, A.; Hashimoto, K.; Kominami, H. J. Am. Chem. Soc. 2012, 134, 14526-14533; (18) Colmenares, J. C.; Magdziarz, A. J. Mol. Cat. A 2013, 366, 156-162 (19) Colmenares, J. C.; Magdziarz, A.; Kurzydlowski, K.; Grzonk, J.; Chernyayeva, O.; Lisovytskiy, D. Appl. Catal. B 2013, 134-135, 136-144 (20) Da Vià, L.; Recchi, C.; Davies, T. E.; Greeves, N.; LopezSanchez, J. A. ChemCatChem 2016, 8, 3475-3483 (21) Da Vià, L.; Recchi, C.; Gonzalez-Yañez, E. O.; Davies, T. E.; Lopez-Sanchez, J. A. Appl. Catal. B, 2017, 202, 281-288 (22) Zhou, B.; Song, J.; Zhang, Z.; Jiang, Z.; Zhang, P.; Han, B. Green Chem. 2017, 19, 1075-1081 (23) Gaeeni, M. R.; Ghamsari, M. S.; Abadi, A. M.; Hossein, M.; Ara, M.; Han, W.; Park, H.-H. J. Am. Ceram. Soc. 2015, 98, 1818– 1822 (24) Omri, M.; Pourceau, G.; Becuwe, M.; Wadouachi, A. ACS Sustain. Chem. Eng. 2016, 4, 2432−2438. (25) Jiang, D.; Wang, W.; Sun, S.; Zhang, L.; Zheng, Y. ACS Catal. 2015, 5, 613-621 (26) Jin, B.; Yao, G.; Wang, X.; Ding, K.; Jin, F. ACS Sustain. Chem. Eng. 2017, 5, 6377-6381 (27) Comotti, M.; Della Pina, C.; Falletta, E.; Rossi, M. Adv. Synth. Catal. 2006, 348, 313-316 (28) Castillo, N. C.; Ding, L.; Heel, A.; Graule, T.; Pulgarin C. J. Photochem. Photobiol. A-Chem. 2010, 216, 221–227
(29) Tseng, D.-H.; Juang, L.-C.; Huang, H.-H. Int. J. Photoenergy, 2012, Article ID 328526 (30) Nosaka, Y.; Nosaka, A.Y. Chem. Rev. 2017, 117, 11302-11336 (31) Diesen, V.; Jonsson, M. J. Phys. Chem. C 2014, 118, 1008310087 (32) Zope, B. N.; Hibbitts, D. D.; Neurock, M.; Davis, R. J. Science, 2010, 330, 74-78 (33) Davis, S. E.; Ide, M. S.; Davis, R. J. Green Chem. 2013, 15, 17-45
Table of Contents (TOC)
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