Tailoring h-BN supported Pd-Cu alloy catalyst for boosted formic acid dehydrogenation

Abstract

Formic acid dehydrogenation offers an efficient method to accomplish hydrogen storage and supply because of its liquid state and high volumetric content of hydrogen at ambient conditions. In this study, we developed and tested h-BN supported Pd-Fe, Pd-Ni, Pd-Co, and Pd-Cu catalysts for formic acid dehydrogenation. Among them, the Pd-Cu/h-BN catalyst synthesized via wet impregnation demonstrates an average productivity of 0.208 mmol/min at 160 °C under catalyst weight at 0.300 g and formic acid feeding rate at 0.008 mL/min, an 84.1% improvement compared to Pd-based catalyst, with minimal CO formation (1.3% CO selectivity at 160 °). Characterizations such as XRD, TEM, and DRIFTS-MS were conducted, confirming PdCu(111) alloy formation with homogeneous metal dispersion. Long-term stability tests showed that the Pd-Cu/h-BN catalyst maintained relatively stable H₂ productivity of 0.210 mmol/min over 2000 min. Density functional theory calculations confirm the superiorities of Pd-Cu alloy compared with Pd/h-BN and Cu/h-BN. These findings underscore potential of Pd-Cu/h-BN as an activated and robust material for hydrogen generation.

Keywords

formic acid dehydrogenation / Pd-Cu alloy / h-BN / CO suppression

References

[1] Sun Z, Sun Z-qiang. Hydrogen generation from methanol reforming for fuel cell applications: A review [J]. Journal of Central South University, 2020, 27(4): 1074-1103.

[2] Gong J-x, Hu S-y, Xiong Y. Designing catalysts to formic acid oxidation reaction: From nanoscale to single atoms [J]. Journal of Central South University, 2024, 31(12): 4586-4600.

[3] Zouheir M, Tanji K, Navio J A, et al.Effective photocatalytic conversion of formic acid using iron, copper and sulphate doped TiO2 [J]. Journal of Central South University, 2022, 29(11): 3592-3607.

[4] Tuluhong A, Chang Q-p, Xie L-r, et al.Current status of green hydrogen production technology: A review [J]. Sustainability, 2024, 16(20): 9070.

[5] Maka A O M, Mehmood M, Chaudhary T N. Green hydrogen revolution and its pathway towards sustainable development [J]. Clean Energy, 2025, 9(2):124-131.

[6] Sedminek A, Likozar B, Gyergyek S. Electrification of selective catalytic liquid organic hydrogen carriers: Hydrogenation and dehydrogenation reactions [J]. ACS Omega, 2024, 9(6): 6027-6035.

[7] Boddien A, Mellmann D, Gärtner F, et al.Efficient dehydrogenation of formic acid using an iron catalyst [J]. Science, 2011, 333(6050): 1733-1736.

[8] Schimmenti R, Mavrikakis M. HCOOH decomposition on sub-nanometer Pd6 cluster catalysts: The effect of defective boron nitride supports through first principles [J]. Applied Catalysis B: Environmental, 2021, 280: 119392.

[9] Wang Y-s, Sun X-x, Liang D-f, et al.Ethanol steam reforming for hydrogen production over alkali metals modified Kaolin-supported Ni catalysts [J]. International Journal of Hydrogen Energy, 2025, 129: 113-129.

[10] Kumar R, Singh R, Dutta S. Review and outlook of hydrogen production through catalytic processes [J]. Energy & Fuels, 2024, 38(4): 2601-2629.

[11] Zhang H-g, Wang Y-l, Li X-m, et al.Electrocatalytic upcycling of polyethylene terephthalate plastic to formic acid coupled with energy-saving hydrogen production over hierarchical Pd-doped NiTe nanoarrays [J]. Applied Catalysis B: Environmental, 2024, 340: 123236.

[12] Wang Y-s, Shen L-l, Liang D-f, et al.Attapulgite-based titanosilicate zeolite-supported Ni catalyst for hydrogen production from catalytic steam reforming of toluene [J]. Journal of Analytical and Applied Pyrolysis, 2024, 177: 106297.

[13] Yao Q-l, Zhang X-l, Lu Z-h, et al.Metal-organic framework-based catalysts for hydrogen production from liquid-phase chemical hydrides [J]. Coordination Chemistry Reviews, 2023, 493: 215302.

[14] Zuo L-j, Yu S-f, Zhang R-j, et al.Tunning Pd-Cu-based catalytic oxygen carrier for intensifying low-temperature methanol reforming [J]. Journal of Cleaner Production, 2023, 410: 137212.

[15] Chen W-q, Wu K-w, Hu J-h, et al.Efficiency of H₂ production influenced by CeO₂ content-dependent copper-ceria interaction [J]. ACS Omega, 2025, 10(8): 8213-8223.

[16] Chen Z-p, Stein C A M, Qu R-y, et al.Designing a robust palladium catalyst for formic acid dehydrogenation [J]. ACS Catalysis, 2023, 13(7): 4835-4841.

[17] Sun Z, Russell C K, Whitty K J, et al.Chemical looping-based energy transformation via lattice oxygen modulated selective oxidation [J]. Progress in Energy and Combustion Science, 2023, 96: 101045.

[18] Chen M-q, Chen C-l, Wang Y-s, et al.Attapulgite-based MCM-41 zeolite supported Ni-Nb catalysts for hydrogen production by acetic acid steam reforming [J]. Fuel, 2024, 361: 130652.

[19] Peng W-f, Sun X-f, Ding Y-y, et al.Enhanced activity of WOx-promoted PdNi nanoclusters confined by amino-modified KIT-6 for dehydrogenation of additive-free formic acid [J]. ACS Sustainable Chemistry & Engineering, 2023, 11(5): 1898-1908.

[20] Chen M-q, Feng X-y, Wang Y-s, et al.Ethanol steam reforming over attapulgite-based MCM-41 supported Ni-Ce-Zr catalyst for hydrogen production [J]. Fuel, 2023, 346: 128373.

[21] Doustkhah E, Hasani M, Ide Y, et al.Pd nanoalloys for H2 generation from formic acid [J]. ACS Applied Nano Materials, 2020, 3(1): 22-43.

[22] Wang Y-s, Lu Z-h, Chen M-q, et al.Hydrogen production from catalytic steam reforming of toluene over trace of Fe and Mn doping Ni/Attapulgite [J]. Journal of Analytical and Applied Pyrolysis, 2022, 165: 105584.

[23] Zhou C-h, Li S, Chai H, et al.Immobilizing Pd nanoparticles on amine-functionalized yolk-shell mesoporous silica nanospheres for efficient H2 production from formic acid dehydrogenation [J]. Applied Catalysis B: Environment and Energy, 2024, 346: 123750.

[24] Zhang H-h, Liu S-l, Shen R-f, et al.Surface-bonded water in h-BN for synergistically triggering catalytic activity to hydrogen generation from ammonia borane via coordination dissociation [J]. Applied Catalysis B: Environment and Energy, 2025, 379: 125729.

[25] Ashraf S, Liu Y-y, Liu S-l, et al.Synergistic electronic interaction in PdCu alloy/TiO2-NSs for ambient efficient dehydrogenation of formic acid [J]. Small, 2025, 21(2): 2407922.

[26] Xie P-n, Yu S-f, Ouyang L-z, et al.Extracting high-purity hydrogen via sodium looping-based formic acid dehydrogenation [J]. International Journal of Hydrogen Energy, 2022, 47(21):11164-11176.

[27] Ding Y-y, Liu P, Huang X-y, et al.Anchoring PdAu nanoclusters inside aminated metal-organic framework for fast dehydrogenation of formic acid [J]. Fuel, 2024, 359: 130459.

[28] Ruiz-López E, Ribota Peláez M, Blasco Ruz M, et al.Formic acid dehydrogenation over ru- and Pd-based catalysts: Gas-vs. Liquid-phase reactions [J]. Materials, 2023, 16(2): 472.

[29] Wu C, Luo M-w, Zhao Y-j, et al.CO2 hydrogenation using MOFs encapsulated PdAg nano-catalysts for formate production [J]. Chemical Engineering Journal, 2023, 475: 146411.

[30] Wang H-l, Wang Z-l, Liu X, et al.AuPd nanocatalysts supported on citric acid-modified boron nitride to boost hydrogen generation from formic acid dehydrogenation [J]. ACS Applied Nano Materials, 2023, 6(5):3285-3292.

[31] Tang W-s, Zhang L-n, Qiu T-y, et al.Efficient conversion of biomass to formic acid coupled with low energy consumption hydrogen production from water electrolysis [J]. Angewandte Chemie International Edition, 2023, 62(30): e202305843.

[32] Wang L, Ji B-f, Zheng Y-p, et al.Asymmetric coordination of iridium single-atom IrN3 O boosting formic acid oxidation catalysis [J]. Angewandte Chemie (International Ed in English), 2023, 62(18):e202301711.

[33] Jiang S, Xiao T-y, Xu C, et al.Passivating oxygen evolution activity of NiFe-LDH through heterostructure engineering to realize high-efficiency electrocatalytic formate and hydrogen co-production [J]. Small, 2023, 19(27):2208027.

[34] Miao B-y, Qiu Z-h, Zhen Z-h, et al.Adsorption and activation of small molecules on boron nitride catalysts [J]. Physical Chemistry Chemical Physics, 2024, 26(14):10494-10505.

[35] Miao Z-l, Zhang R-j, Li H-w, et al.Catalytic formic acid dehydrogenation via hexagonal-boron nitride supported palladium [J]. International Journal of Hydrogen Energy, 2024, 49: 602-612.

[36] Xu R, Lu W-q, Toan S, et al.Thermocatalytic formic acid dehydrogenation: Recent advances and emerging trends [J]. Journal of Materials Chemistry A, 2021, 9(43): 24241-24260.

[37] Li Y-h, Deng H-c, Zhou Z-h, et al.Pd12Ag1 nanoalloy on dendritic CNFs catalyst for boosting formic acid oxidation [J]. Applied Surface Science, 2023, 608: 155131.

[38] Yu S, Yong H, Zhao Y, et al.Synergistic catalytic effects of Ni MOF catalyst and RE alloying on the hydrogen absorption/desorption kinetics of MgH2 [J]. Materials Letters, 2023, 348: 134674.

[39] Yruela-Garrido M, Campos-Castellanos E, Morales M V, et al.Boron nitride-supported metal catalysts for the synthesis and decomposition of ammonia and formic acid [J]. Nanomaterials, 2025, 15(3): 212.

[40] Sun Q-m, Chen B W J, Wang N, et al.Zeolite-encaged Pd-Mn nanocatalysts for CO2 hydrogenation and formic acid dehydrogenation [J]. Angewandte Chemie International Edition, 2020, 59(45):20183-20191.

[41] Bulushev D A, Zacharska M, Shlyakhova E V, et al.Single isolated Pd2+ cations supported on N-doped carbon as active sites for hydrogen production from formic acid decomposition [J]. ACS Catalysis, 2016, 6(2): 681-691.

[42] Perdew J P, Burke K, Ernzerhof M. Generalized gradient approximation made simple [J]. Physical Review Letters, 1996, 77(18): 3865-3868.

[43] Hammer B, Hansen L B, Nørskov J K. Improved adsorption energetics within density-functional theory using revised Perdew-Burke-Ernzerhof functionals [J]. Physical Review B, 1999, 59(11): 7413-7421.

[44] Kresse G, Joubert D. From ultrasoft pseudopotentials to the projector augmented-wave method [J]. Physical Review B, 1999, 59(3): 1758-1775.

[45] Monkhorst H J, Pack J D. Special points for Brillouin-zone integrations [J]. Physical Review B, 1976, 13(12): 5188-5192.

[46] Henkelman G, Jónsson H. Improved tangent estimate in the nudged elastic band method for finding minimum energy paths and saddle points [J]. The Journal of Chemical Physics, 2000, 113(22): 9978-9985.

[47] Henkelman G, Uberuaga B P, Jónsson H. A climbing image nudged elastic band method for finding saddle points and minimum energy paths [J]. The Journal of Chemical Physics, 2000, 113(22): 9901-9904.

[48] Sheppard D, Henkelman G. Paths to which the nudged elastic band converges [J]. Journal of Computational Chemistry, 2011, 32(8): 1769-1771.

[49] Grimme S, Antony J, Ehrlich S, et al.A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu [J]. The Journal of Chemical Physics, 2010, 132(15): 154104.

[50] Makov G, Payne M C. Periodic boundary conditions in ab initio calculations [J]. Physical Review B, Condensed Matter, 1995, 51(7):4014-4022.

[51] Wang V, Xu N, Liu J-c, et al.VASPKIT: A user-friendly interface facilitating high-throughput computing and analysis using VASP code [J]. Computer Physics Communications, 2021, 267: 108033.

[52] Winkler T, Baccot F, Eränen K-r, et al.Catalytic decomposition of formic acid in a fixed bed reactor-an experimental and modelling study [J]. Catalysis Today, 2022, 387: 128-139.

[53] Ojeda M, Iglesia E. Formic acid dehydrogenation on Au-based catalysts at near-ambient temperatures [J]. Angewandte Chemie, 2009, 121(26): 4894-4897.

[54] Koós Á, Solymosi F. Production of CO-free H2 by formic acid decomposition over Mo2C/carbon catalysts [J]. Catalysis Letters, 2010, 138(1): 23-27.

[55] Solymosi F, Koós Á, Liliom N, et al.Production of CO-free H2 from formic acid. A comparative study of the catalytic behavior of Pt metals on a carbon support [J]. Journal of Catalysis, 2011, 279(1): 213-219.

[56] Gazsi A, Bánsági T, Solymosi F. Decomposition and reforming of formic acid on supported Au catalysts: Production of CO-free H2 [J]. The Journal of Physical Chemistry C, 2011, 115(31): 15459-15466.

[57] Piazza V, Junior R B S, Gazzoli D, et al.H2 from biofuels and carriers: A kinetic investigation of formic acid decomposition on Rh/Al2O3 in the annular reactor [J]. Chemical Engineering Research and Design, 2022, 181: 458-472.

[58] Jia L-j, Bulushev D A, Beloshapkin S, et al.Hydrogen production from formic acid vapour over a Pd/C catalyst promoted by potassium salts: Evidence for participation of buffer-like solution in the pores of the catalyst [J]. Applied Catalysis B: Environmental, 2014, 160: 35-43.

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