10.1002/cctc.201901930
ChemCatChem
FULL PAPER
Preparation of CN: To remove the ZrO2 with the obtained black powder,
the CN-ZrO2 was treated with HF (20 wt%) at room temperature for 12 h
and was washed with deionized water (5X) and methanol (3X). The
washed CN samples were dried at 60 °C under a vacuum (30 mTorr) for
6 h.
This work acknowledges the financial support from Iowa State
University and the China University of Petroleum-Beijing. We
thank Gordon J. Miller for the use of the XRD instrument,
Dapeng Jing for the assistance of XPS measurement, and
Xinwei Wang for the Raman spectra measurement.
Preparation of Pt/CN-ZrO2: The MOF-derived carbon was utilized as a
support to embed Pt NPs by a simple solution impregnation method
(designed as Pt/CN-ZrO2).[18] CN-ZrO2 (50 mg) was dispersed in 2 mL
H2O and sonicated for 30 minutes to achieve uniform dispersion. 0.5 mL
of 0.04 M K2PtCl4, Aqueous solution was slowly added to the above
solution. The mixture was stirred at room temperature for 38 h. The as-
prepared Pt/CN-ZrO2 was then isolated by a centrifuge, washed three
times with fresh water, and dried at 60 ºC for 1 h under a vacuum to yield
Pt/CN-ZrO2. Finally, the sample was reduced to under a 50 mL/min flow
of 10% H2/Ar at 200 °C for 2 h. The Pt/CN was prepared by following the
same procedure.
Keywords: metal-organic frameworks (MOFs) • n-doped
carbons • platinum • one-step • condensation-hydrogenation •
tandem reaction
[1]
a) F. X. Felpin, E. Fouquet, ChemSusChem: Chemistry & Sustainability
Energy & Materials. 2008, 1, 718-724; b) B. Brooks, Green Chem.
2019, 21, 2575-2582.
[2]
[3]
X. Li, B. Zhang, Y. Fang, W. Sun, Z. Qi, Y. Pei, S. Qi, P. Yuan, X. Luan,
T. W. Goh, Chem. Eur. J. 2017, 23, 4266-4270.
Characterization: Powder X-ray diffraction (PXRD) patterns of the
samples were obtained by a STOE Stadi P powder diffractometer using
Cu Kα radiation (40 kV, 40 mA, λ = 0.1541 nm). N2 physisorption
a) A. Jana, C. B. Reddy, B. Maji, ACS Catal. 2018, 8, 9226-9231; b) S.
S. Kulp, M. J. McGee, J. Org. Chem. 1983, 48, 4097-4098; c) R. W.
Hartmann, C. Batzl, J. Med. Chem. 1986, 29, 1362-1369; d) K.
Motokura, D. Nishimura, K. Mori, T. Mizugaki, K. Ebitani, K. Kaneda, J.
Am. Chem. Soc. 2004, 126, 5662-5663.
measurements were performed with
a Micromeritics 3Flex surface
characterization analyzer at 77 K. All samples were activated at 200 °C
for 10 h under a vacuum (< 10–5 torr) before the measurements. The
size and morphology of 0.87 wt% Pt/CN-ZrO2 were measured using
transmission electron microscopy (TEM). TEM images were obtained
with a Tecnai G2 F20 electron microscope operated at 200 kV. High
angle annular dark-field scanning transmission electron microscope
(HAADF-STEM) images were obtained on a Titan Themis 300 probe-
[4]
[5]
[6]
a) R. Nie, M. Chen, Y. Pei, B. Zhang, L. Qi, J. Chen, T. W. Goh, Z. Qi, Z.
Zhang, W. Huang, ACS Sustainable Chem. Eng. 2018, 7, 3356-3363;
b) L. Zexiang, J. Shengfu, L. Hui, L. Chengyue, Chin. J. Chem. Eng.
2008, 16, 740-745.
a) X. Li, B. Lin, H. Li, Q. Yu, Y. Ge, X. Jin, X. Liu, Y. Zhou, J. Xiao, Appl.
Catal. B: Environ 2018, 239, 254-259; b) Y. Ono, J. Catal. 2003, 216,
406-415; c) S. K. Panja, N. Dwivedi, S. Saha, RSC Adv. 2015, 5,
65526–65531.
corrected TEM instrument with
spectroscopy (EDX) detector. Raman spectra were acquired by
confocal Raman system (Voyage, B&W Tek, Inc.) with spectral
a Super-X energy-dispersive X-ray
a
a
resolution of 1.05~1.99 cm-1. A 532 nm CW laser was used as the
excitation source with a laser power of 0.1 mW, a 20 × objective lens,
a) W. F. Hoelderich, Catal. Today 2000, 62, 115-130; b) G. Goerner, H.
Muller, J. Corbin, J. Org. Chem. 1959, 24, 1561-1563; c) E.
Knoevenagel, Ber. Dtsch. Chem. Ges. 1894, 27, 2345-2346; d) E.
Knoevenagel, Ber. Dtsch. Chem. Ges. 1896, 29, 172-174; e) G. Jones,
Org. React. 2004, 15, 204-599.
and
a
10
s
integration time.
Inductively coupled plasma-mass
spectrometry (ICP-MS, X Series II, Thermo Scientific) measurements
were performed to determine the actual metal content. Before the ICP
analysis, the samples were heated in a box furnace to 550 ºC for 4 h,
then treated with HF (20 wt%) at 60 °C for 2 h, then digested with boiled
aqua regia. X-ray photoelectron spectroscopy (XPS) measurements were
performed on a PHI 5500 Multitechnique system (Physical Electronics,
Chanhassen, MN, USA) equipped with a monochromatized Al Kα X-ray
source (1486.6 eV). CO2 temperature-programmed desorption (TPD)
[7]
[8]
S. Erhardt, V. V. Grushin, A. H. Kilpatrick, S. A. Macgregor, W. J.
Marshall, D. C. Roe, J. Am. Chem. Soc. 2008, 130, 4828-4845.
a) P. Li, H. Liu, Y. Yu, C. Y. Cao, W. G. Song, Chemistry–An Asian
Journal 2013, 8, 2459-2465; b) P. Li, Y. Yu, H. Liu, C. Y. Cao, W. G.
Song, Nanoscale 2014, 6, 442-448; c) E. Verde-Sesto, E. Merino, E.
Rangel-Rangel, A. Corma, M. Iglesias, F. l. Sánchez, ACS Sustainable
Chem. Eng. 2016, 4, 1078-1084; d) Z. Liu, X. Tong, J. Liu, S. Xue, Catal
Sci Technol. 2016, 6, 1214-1221; e) K. Motokura, N. Fujita, K. Mori, T.
Mizugaki, K. Ebitani, K. Jitsukawa, K. Kaneda, Chem. Eur. J. 2006, 12,
8228-8239.
experiments were carried out on
a Micromeritics 3Flex instrument
equipped with a mass spec detector. Typically, the sample (ca.100 mg)
was pretreated under a flow of Helium (50 mL/min) at 300 ºC for 1 h.
Then, the sample was cooled to 30 °C under a flow of Helium and
adsorbed CO2 for 2 h. Finally, the sample was purged with Helium (50
mL/min) at 30 ºC for 30 minutes. The TPD data were collected from
30 °C to 300 °C at a heating rate of 5 °C/min in a flow of Helium.
[9]
a) Z. Qi, Y. Pei, T. W. Goh, Z. Wang, X. Li, M. Lowe, R. V. Maligal-
Ganesh, W. Huang, Nano Res. 2018, 11, 3469-3479; b) F. Rodriguez-
Reinoso, A. Sepulveda-Escribano, Cheminform. 2010, 40; c) D. S. Su,
S. Perathoner, G. Centi, Chem. Rev. 2013, 113, 5782-5816; d) S. Zhao,
X. Lu, L. Wang, J. Gale, R. Amal, Adv. Mater. 2019, 31, 1805367; e) P.
Gholami, A. Khataee, R. D. C. Soltani, A. Bhatnagar, Ultrasonics
Sonochemistry. 2019, 58, 104681; f) R. Ströbel, L. Jörissen, T.
Schliermann, V. Trapp, W. Schütz, K. Bohmhammel, G. Wolf, J.
Garche, J. Power Sources. 1999, 84, 221-224; g) J. Lee, J. Kim, T.
Hyeon, Adv. Mater. 2006, 18, 2073-2094.
Catalyst Evaluation: In a typical tandem Knoevenagel condensation-
hydrogenation reaction, 0.1 mmol of benzylaldehyde, 0.2 mmol of
malononitrile, 2 mL of EtOH, and 5 mg of catalyst were charged in a
stainless-steel autoclave with a Teflon liner. The autoclave was sealed,
purged, and pressurized with hydrogen to 1 MPa and then stirred at
80 °C at a rate of 600 rpm. After the reaction, the catalyst was recovered
by centrifugation, and the supernatant was quantitatively analyzed using
a gas chromatograph (Hewlett-Packard 5890 II, FID detector) equipped
with a HP-5 capillary column. Xylene was used as the internal standard.
The identification of products was conducted by using an Agilent
6890N/5975 GC-MS system.
[10] a) H. Chen, K. Shen, Q. Mao, J. Chen, Y. Li, ACS Catal. 2018, 8, 1417-
1426; b) H. Chen, K. Shen, Y. Tan, Y. Li, ACS Nano 2019, 13, 7800-
7810; c) S. i. Fujita, A. Katagiri, H. Watanabe, S. Asano, H. Yoshida, M.
Arai, ChemCatChem 2015, 7, 2965-2970; d) L. Liu, Y. Yin, J. Li, S.
Wang, Y. Guo, L. Wan, Adv. Mater. 2018, 30, 1706216; e) Y. Xu, C.
Zhang, M. Zhou, Q. Fu, C. Zhao, M. Wu, Y. Lei, Nat. Commun. 2018, 9,
1720; f) X. Yuan, M. Zhang, X. Chen, N. An, G. Liu, Y. Liu, W. Zhang,
W. Yan, M. Jia, Appl. Catal. A. 2012, 439, 149-155; g) S. Kundu, W. Xia,
W. Busser, M. Becker, D. A. Schmidt, M. Havenith, M. Muhler, Phys.
Chem. Chem. Phys. 2010, 12, 4351-4359.
Acknowledgements
This article is protected by copyright. All rights reserved.