Mechanism of methanol decomposition on the Pd/WC(0001) surface unveiled by first-principles calculations
Jinhua Zhang1,2, Yuanbin She1()
1. College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China 2. School of Materials and Environmental Engineering, Chizhou University, Chizhou 247000, China
In this study, the decomposition of methanol into the CO and H species on the Pd/tungsten carbide (WC)(0001) surface is systematically investigated using periodic density functional theory (DFT) calculations. The possible reaction pathways and intermediates are determined. The results reveal that saturated molecules, i.e., methanol and formaldehyde, adsorb weakly on the Pd/ WC(0001) surface. Both CO and H prefer three-fold sites, with adsorption energies of −1.51 and −2.67 eV, respectively. On the other hand, CH3O stably binds at three-fold and bridge sites, with an adsorption energy of −2.58 eV. However, most of the other intermediates tend to adsorb to the surface with the carbon and oxygen atoms in their sp3 and hydroxyl-like configurations, respectively. Hence, the C atom of CH2OH preferentially attaches to the top sites, CHOH and CH2O adsorb at the bridge sites, while COH and CHO occupy the three-fold sites. The DFT calculations indicate that the rupture of the initial C–H bond promotes the decomposition of CH3OH and CH2OH, whereas in the case of CHOH, O–H bond scission is favored over the C–H bond rupture. Thus, the most probable methanol decomposition pathway on the Pd/WC(0001) surface is CH3OH → CH2OH → trans-CHOH → CHO → CO. The present study demonstrates that the synergistic effect of WC (as carrier) and Pd (as catalyst) alters the CH3OH decomposition pathway and reduces the noble metal utilization.
. [J]. Frontiers of Chemical Science and Engineering, 2020, 14(6): 1052-1064.
Jinhua Zhang, Yuanbin She. Mechanism of methanol decomposition on the Pd/WC(0001) surface unveiled by first-principles calculations. Front. Chem. Sci. Eng., 2020, 14(6): 1052-1064.
J C C Gomez, R Moliner, M J Lazaro. Palladium-based catalysts as electrodes for direct methanol fuel cells: A last ten years review. Catalysts, 2016, 6(9): 1–20
2
H Y Lian, X S Li, J L Liu, A M Zhu. Methanol steam reforming by heat-insulated warm plasma catalysis for efficient hydrogen production. Catalysis Today, 2019, 337: 76–82 https://doi.org/10.1016/j.cattod.2019.03.068
3
R Garcia-Muelas, Q Li, N Lopez. Density functional theory comparison of methanol decomposition and reverse reactions on metal surfaces. ACS Catalysis, 2015, 5(2): 1027–1036 https://doi.org/10.1021/cs501698w
4
Z Jiang, B Wang, T Fang. A theoretical study on the complete dehydrogenation of methanol on Pd (100) surface. Applied Surface Science, 2016, 364: 613–619 https://doi.org/10.1016/j.apsusc.2015.12.204
5
X Q Lu, W L Wang, Z G Deng, H Y Zhu, S X Wei, S P Ng, W Y Guo, C M L Wu. Methanol oxidation on Ru(0001) for direct methanol fuel cells: Analysis of the competitive reaction mechanism. RSC Advances, 2016, 6(3): 1729–1737 https://doi.org/10.1039/C5RA21793H
6
M Zhang, X Wu, Y Yu. A comparative DFT study on the dehydrogenation of methanol on Rh(100) and Rh(110). Applied Surface Science, 2018, 436: 268–276 https://doi.org/10.1016/j.apsusc.2017.12.040
7
K C Shen, C G Jia, B X Cao, H Xu, J Wang, L C Zhang, K Kim, W M Wang. Comparison of catalytic activity between Au(110) and Au(111) for the electro-oxidation of methanol and formic acid: Experiment and density functional theory calculation. Electrochimica Acta, 2017, 256: 129–138 https://doi.org/10.1016/j.electacta.2017.10.026
8
Z Jiang, S Y Guo, T Fang. Theoretical investigation on the dehydrogenation mechanism of CH3OH on Cu(100) surface. Journal of Alloys and Compounds, 2017, 698: 617–625 https://doi.org/10.1016/j.jallcom.2016.12.220
9
L N Liu, H D Yao, Z Jiang, T Fang. Theoretical study of methanol synthesis from CO2 hydrogenation on PdCu3(111) surface. Applied Surface Science, 2018, 451: 333–345 https://doi.org/10.1016/j.apsusc.2018.04.128
10
P Du, P Wu, C X Cai. Mechanism of methanol decomposition on the Pt3Ni(111) surface: DFT study. Journal of Physical Chemistry C, 2017, 121(17): 9348–9360 https://doi.org/10.1021/acs.jpcc.7b01114
11
L N Liu, F Fan, M M Bai, F Xue, X R Ma, Z Jiang, T Fang. Mechanistic study of methanol synthesis from CO2 hydrogenation on Rh-doped Cu(111) surfaces. Molecular Catalysis, 2019, 466: 26–36 https://doi.org/10.1016/j.mcat.2019.01.009
12
L H Ou. Theoretical insights into the effect of solvation and sublayer Ru on Pt-catalytic CH3OH oxidation mechanisms in the aqueous phase. Journal of Physical Chemistry C, 2018, 122(26): 14554–14565 https://doi.org/10.1021/acs.jpcc.8b03010
13
X Jiang, X W Nie, X X Wang, H Z Wang, N Koizumi, Y G Chen, X W Guo, C S Song. Origin of Pd-Cu bimetallic effect for synergetic promotion of methanol formation from CO2 hydrogenation. Journal of Catalysis, 2019, 369: 21–32 https://doi.org/10.1016/j.jcat.2018.10.001
14
J Y Ye, C J Liu, Q F Ge. A DFT study of methanol dehydrogenation on the PdIn(110) surface. Physical Chemistry Chemical Physics, 2012, 14(48): 16660–16667 https://doi.org/10.1039/c2cp42183f
15
J H Meng, A M Carl, M B Zellner, J G Chen. Effects of bimetallic modification on the decomposition of CH3OH and H2O on Pt/W(110) bimetallic surfaces. Surface Science, 2010, 604(21-22): 1845–1853 https://doi.org/10.1016/j.susc.2010.07.015
16
J Y Damte, S L Lyu, E G Leggesse, J C Jiang. Methanol decomposition reactions over a boron-doped graphene supported Ru-Pt catalyst. Physical Chemistry Chemical Physics, 2018, 20(14): 9355–9363 https://doi.org/10.1039/C7CP07618E
17
A D Allian, K Takanabe, K L Fujdala, X Hao, T J Truex, J Cai, C Buda, M Neurock, E Iglesia. Chemisorption of CO and mechanism of CO oxidation on supported platinum nanoclusters. Journal of the American Chemical Society, 2011, 133(12): 4498–4517 https://doi.org/10.1021/ja110073u
18
Y B Lu, J M Wang, L Yu, L Kovarik, X W Zhang, A S Hoffman, A Gallo, S R Bare, D Sokaras, T Kroll, V Dagle, H Xin, A M Karim. Identification of the active complex for CO oxidation over single-atom Ir-on-MgAl2O4 catalysts. Nature Catalysis, 2019, 2(2): 149–156 https://doi.org/10.1038/s41929-018-0192-4
19
M Kubler, T Jurzinsky, D Ziegenbalg, C Cremers. Methanol oxidation reaction on core-shell structured Ruthenium-Palladium nanoparticles: Relationship between structure and electrochemical behavior. Journal of Power Sources, 2018, 375: 320–334 https://doi.org/10.1016/j.jpowsour.2017.07.114
20
L M Luo, R H Zhang, D Chen, Q Y Hu, X Zhang, C Y Yang, X W Zhou. Hydrothermal synthesis of PdAu nanocatalysts with variable atom ratio for methanol oxidation. Electrochimica Acta, 2018, 259: 284–292 https://doi.org/10.1016/j.electacta.2017.10.177
21
M G Hosseini, R Mahmoodi, V Daneshvari-Esfahlan. Ni@Pd core-shell nanostructure supported on multi-walled carbon nanotubes as efficient anode nanocatalysts for direct methanol fuel cells with membrane electrode assembly prepared by catalyst coated membrane method. Energy, 2018, 161: 1074–1084 https://doi.org/10.1016/j.energy.2018.07.148
22
T Jurzinsky, R Bar, C Cremers, J Tubke, P Elsner. Highly active carbon supported palladium-rhodium PdXRh/C catalysts for methanol electrooxidation in alkaline media and their performance in anion exchange direct methanol fuel cells. Electrochimica Acta, 2015, 176: 1191–1201 https://doi.org/10.1016/j.electacta.2015.07.176
23
L N Liu, F Fan, Z Jiang, X F Gao, J J Wei, T Fang. Mechanistic study of Pd‒Cu bimetallic catalysts for methanol synthesis from CO2 hydrogenation. Journal of Physical Chemistry C, 2017, 121(47): 26287–26299 https://doi.org/10.1021/acs.jpcc.7b06166
24
P P Wu, B Yang. Theoretical insights into the promotion effect of subsurface boron for the selective hydrogenation of CO to methanol over Pd catalysts. Physical Chemistry Chemical Physics, 2016, 18(31): 21720–21729 https://doi.org/10.1039/C6CP02735K
25
X Jiang, Y Jiao, C Moran, X W Nie, Y T Gong, X W Guo, K S Walton, C S Song. CO2 hydrogenation to methanol on Pd‒Cu bimetallic catalysts with lower metal loadings. Catalysis Communications, 2019, 118: 10–14 https://doi.org/10.1016/j.catcom.2018.09.006
26
L Lu, X F Sun, J Ma, D X Yang, H H Wu, B X Zhang, J L Zhang, B X Han. Highly efficient electroreduction of CO2 to methanol on palladium-copper bimetallic aerogels. Angewandte Chemie International Edition, 2018, 57(43): 14149–14153 https://doi.org/10.1002/anie.201808964
27
X Liu, Y Men, J G Wang, R He, Y Q Wang. Remarkable support effect on the reactivity of Pt/In2O3/MOx catalysts for methanol steam reforming. Journal of Power Sources, 2017, 364: 341–350 https://doi.org/10.1016/j.jpowsour.2017.08.043
28
N Kruse, M Rebholz, V Matolin, G K Chuah, J H Block. Methanol decomposition on Pd(111) single-crystal surfaces. Surface Science, 1990, 238(1-3): L457–L462 https://doi.org/10.1016/0039-6028(90)90054-C
29
R Jiang, W Guo, M Li, D Fu, H Shan. Density functional investigation of methanol dehydrogenation on Pd(111). Journal of Physical Chemistry C, 2009, 113(10): 4188–4197 https://doi.org/10.1021/jp810811b
30
V M Nikolic, D L Zugic, I M Perovic, A B Saponjic, B M Babic, I A Pasti, M P M Kaninski. Investigation of tungsten carbide supported Pd or Pt as anode catalysts for PEM fuel cells. International Journal of Hydrogen Energy, 2013, 38(26): 11340–11345 https://doi.org/10.1016/j.ijhydene.2013.06.094
31
D D Vasic, I A Pasti, S V Mentus. DFT study of platinum and palladium overlayers on tungsten carbide: Structure and electrocatalytic activity toward hydrogen oxidation/evolution reaction. International Journal of Hydrogen Energy, 2013, 38(12): 5009–5018 https://doi.org/10.1016/j.ijhydene.2013.02.020
32
N R Elezovic, P Zabinski, P Ercius, M Wytrwal, V R Radmilovic, U C Lacnjevac, N V Krstajic. High surface area Pd nanocatalyst on core-shell tungsten based support as a beneficial catalyst for low temperature fuel cells application. Electrochimica Acta, 2017, 247: 674–684 https://doi.org/10.1016/j.electacta.2017.07.066
33
J S Moon, Y W Lee, S B Han, K W Park. Pd nanoparticles on mesoporous tungsten carbide as a non-Pt electrocatalyst for methanol electrooxidation reaction in alkaline solution. International Journal of Hydrogen Energy, 2014, 39(15): 7798–7804 https://doi.org/10.1016/j.ijhydene.2014.03.154
34
Q Zhang, Z J Mellinger, Z Jiang, X Chen, B Wang, B Y Tian, Z X Liang, J G G Chen. Palladium-modified tungsten carbide for ethanol electrooxidation: From surface science studies to electrochemical evaluation. Journal of the Electrochemical Society, 2018, 165(15): J3031–J3038 https://doi.org/10.1149/2.0061815jes
35
H Y Park, I S Park, B Choi, K S Lee, T Y Jeon, Y E Sung, S J Yoo. Pd nanocrystals on WC as a synergistic electrocatalyst for hydrogen oxidation reactions. Physical Chemistry Chemical Physics, 2013, 15(6): 2125–2130 https://doi.org/10.1039/c2cp43262e
36
Z J Mellinger, T G Kelly, J G Chen. Pd-modified tungsten carbide for methanol electro-oxidation: From surface science studies to electrochemical evaluation. ACS Catalysis, 2012, 2(5): 751–758 https://doi.org/10.1021/cs200620x
37
B Delley. From molecules to solids with the DMol(3) approach. Journal of Chemical Physics, 2000, 113(18): 7756–7764 https://doi.org/10.1063/1.1316015
38
J P Perdew, K Burke, M Ernzerhof. Generalized gradient approximation made simple. Physical Review Letters, 1996, 77(18): 3865–3868 https://doi.org/10.1103/PhysRevLett.77.3865
39
X Wang, L Chen, B Li. A density functional theory study of methanol dehydrogenation on the PtPd3(111) surface. International Journal of Hydrogen Energy, 2015, 40(31): 9656–9669 https://doi.org/10.1016/j.ijhydene.2015.06.028
40
M Zhang, X Wu, Y Yu. A comparative DFT study on the dehydrogenation of methanol on Rh(100) and Rh(110). Applied Surface Science, 2018, 436: 268–276 https://doi.org/10.1016/j.apsusc.2017.12.040
41
V Orazi, P Bechthold, P V Jasen, R Faccio, M E Pronsato, E A González. DFT study of methanol adsorption on PtCo(111). Applied Surface Science, 2017, 420: 383–389 https://doi.org/10.1016/j.apsusc.2017.05.159
42
D R Lide. CRC Handbook of chemistry and physics: A ready-reference book of chemical and physical data. CRC Press, 2004, 152–155
43
X Zhang, Z Lu, Z Yang. A comparison study of oxygen reduction on the supported Pt, Pd, Au monolayer on WC(0001). Journal of Power Sources, 2016, 321: 163–173 https://doi.org/10.1016/j.jpowsour.2016.04.135
44
H Y Park, I S Park, B Choi, K S Lee, T Y Jeon, Y E Sung, S J Yoo. Pd nanocrystals on WC as a synergistic electrocatalyst for hydrogen oxidation reactions. Physical Chemistry Chemical Physics, 2013, 15(6): 2125–2130 https://doi.org/10.1039/c2cp43262e
45
J Miragliotta, R S Polizzotti, P Rabinowitz, S D Cameron, R B Hall. Ir-visible sum-frequency generation study of methanol adsorption and reaction on Ni(100). Chemical Physics, 1990, 143(1): 123–130 https://doi.org/10.1016/0301-0104(90)85012-L
46
C J Zhang, P Hu. A first principles study of methanol decomposition on Pd(111): Mechanisms for O–H bond scission and C–O bond scission. Journal of Chemical Physics, 2001, 115(15): 7182–7186 https://doi.org/10.1063/1.1405157
47
S K Desai, M Neurock, K Kourtakis. A periodic density functional theory study of the dehydrogenation of methanol over Pt(111). Journal of Physical Chemistry B, 2002, 106(10): 2559–2568 https://doi.org/10.1021/jp0132984
48
J A Gates, L L Kesmodel. Methanol adsorption and decomposition on clean and oxygen precovered palladium (111). Journal of Catalysis, 1983, 83(2): 437–445 https://doi.org/10.1016/0021-9517(83)90068-4
J J Chen, Z C Jiang, Y Zhou, B R Chakraborty, N Winograd. Spectroscopic studies of methanol decomposition on Pd(111). Surface Science, 1995, 328(3): 248–262 https://doi.org/10.1016/0039-6028(95)00007-0
51
R J Levis, Z C Jiang, N Winograd. Thermal-decomposition of CH3OH adsorbed on Pd(111)—a new reaction pathway involving CH3 formation. Journal of the American Chemical Society, 1989, 111: 4605–4612 https://doi.org/10.1021/ja00195a013
52
I N Remediakis, F Abild-Pedersen, J K Norskov. DFT study of formaldehyde and methanol synthesis from CO and H2 on Ni(111). Journal of Physical Chemistry B, 2004, 108(38): 14535–14540 https://doi.org/10.1021/jp0493374
53
J Kua, W A Goddard. Oxidation of methanol on 2nd and 3rd row Group VIII transition metals (Pt, Ir, Os, Pd, Rh and Ru): Application to direct methanol fuel cells. Journal of the American Chemical Society, 1999, 121(47): 10928–10941 https://doi.org/10.1021/ja9844074
54
R B Jiang, W Y Guo, M Li, X Q Lu, J Y Yuan, H H Shan. Dehydrogenation of methanol on Pd(100): Comparison with the results of Pd(111). Physical Chemistry Chemical Physics, 2010, 12(28): 7794–7803 https://doi.org/10.1039/b927050g
55
T E Felter, E C Sowa, M A Vanhove. Location of hydrogen adsorbed on palladium(111) studied by low-energy electron-diffraction. Physical Review. B, 1989, 40(2): 891–899 https://doi.org/10.1103/PhysRevB.40.891
