ACS Applied Energy Materials
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2023
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IF 6.4
Shuozhen Hu,Zhaoqun Gao,Sijie Gao,Junyu Wang,Xinsheng Zhang
Pd-based alloys, especially for alloys containing early transition metals, have been extensively designed and applied to electro-oxidize formic acid for direct formic acid fuel cells owing to their capability to directly oxidize formic acid molecules via the dehydrogenation pathway. Adjusting the strain and electronic effects of Pd-based alloys is an effective method to regulate the adsorbing phenomena of intermediates on catalysts during formic acid oxidation and improve the catalytic activity and stability. The ordering degree of alloys plays an important role in modulating the adsorbing ability. In this work, we report a strategy varying the atomic ordering degree of PdCoNi/rGO trimetallic alloys to manipulate the strain and electronic effects and electrocatalytic performance toward formic acid oxidation. A series of PdCoNi/rGO-T trimetallic catalysts are synthesized, in which the atomic order of the trimetallic catalysts is regulated by annealing the wet-chemistry-synthesized PdCoNi/rGO alloy. As the annealing temperature increases, the atomic arrangement among Pd, Co, and Ni is ordered. Eventually, ordered intermetallic PdCoNi/rGO-T catalysts are generated. As the atomic ordering degree increases, the lattice constant decreases, and more charge transfers from Pd to Ni and Co, leading to enhanced strain and electronic effects. Moreover, the ordered intermetallic structure stabilizes Co and Ni atoms to prevent the dissolution of the transition metals in acidic electrolyte, and the strain and electronic effects in ordered PdCoNi/rGO catalysts are maintained. With an annealing temperature of 700 °C, the intermetallic PdCoNi/rGO-700 exhibits the highest specific activity of 8.33 mA/cm2, which is 1.95-fold improved compared to pristine PdCoNi/rGO alloy (3.23 mA/cm2) and 2.48 times compared to Pd/rGO-700 (2.54 mA/cm2). Moreover, PdCoNi/rGO-700 also shows outstanding catalytic durability due to its excellent structural stability. We believe that this research helps in developing Pd-based alloy catalysts with high activity and stability for formic acid electro-oxidation.
研究领域:
材料科学
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电化学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2023
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IF 7.3
Kechuang Wan,Haitao Chen,Jue Wang,Bing Li,Maorong Chai,Pingwen Ming,Cunman Zhang
Atomically ordered intermetallic catalysts have great potential for catalyzing efficient oxygen reduction reaction (ORR), while the coupling of metal and support are not emphasized enough. Herein, we report an atomically ordered PtCo bimetallic catalyst coupled with N-doped ultrathin carbon shells (PtCo/NCS) for ORR by a facile natural ligand annealing strategy. The formed NCS prevents the high-temperature sintering of catalysts by physical confinement, and the coupling effect results in a stronger affinity between PtCo and NCS for PtCo/NCS. The optimal PtCo/NCS-5 exhibits more exceptional activity and durability, outperforming commercial Pt/C and Pt 3 Co/C catalysts (C-Pt 3 Co/C). It is proved that PtCo and NCS synergically account for the enhanced ORR performance for PtCo/NCS-5. More importantly, the compressive lattice strain effectively promotes electron redistribution and optimizes the electronic structure for PtCo/NCS-5. This work further deepens the understanding of catalytic mechanisms and provides new insight into the rational design of advanced electrocatalysts toward ORR.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2025
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IF 21.1
Ning Sun,Yang Qin,Gongjin Xu,Yalei Fan,Bowen Zhang,Yu-Cheng Huang,Ying-Rui Lu,Xiangjiang Dong,Lei Lian,Zhichuan Zheng,Ruyue Wang,Qingyu Kong,Zhiwei Hu,Linjuan Zhang,Ming Lei,Kai Huang,Runze Yu
Atomic-scale modulation of crystalline ordering in heterogeneous catalysts offers a critical pathway to enhance reaction kinetics, yet fundamental understanding of how their dynamic structural evolution governs active-site stability remains elusive. Here, we decode these effects by precisely engineering crystallographic gradients from ordered to disordered states, within octahedral building blocks (isolated octahedra [MO 6 ] or dimer [M 2 O 9 ]) of perovskite oxides Ba 3 M x Ru 2-x O 9 (M = Fe, Co). This atomic-level control induces systematic shifts in d / p -band centers and optimizes charge distribution architectures within active regions. Crucially, the highly disordered Ba 3 FeRu 2 O 9 achieves exceptional stability via a self-sacrificial reduction of iron, which generates a built-in electric field (BEF). The BEF promotes optimal adsorption/desorption kinetics of OH*/H* intermediates for the hydrogen evolution reaction (HER). Consequently, Ba 3 FeRu 2 O 9 delivers benchmark alkaline HER performance, achieving an overpotential of just 24 mV at 10 mA cm −2 and demonstrating operational stability exceeding 600 h. Our results reveal that structural reorganization, enabled by atomic-level ordering modulation, is critical for establishing dynamic structure-performance frameworks to guide advanced catalyst design.
研究领域:
材料化学
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电化学
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催化化学
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固态化学
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能源材料
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Wei Liu,Yusen Yang,Lifang Chen,Enze Xu,Jiaming Xu,Song Hong,Xin Zhang,Min Wei
Activation of oxygen-containing functional groups plays a key role in sustainable biomass upgrading and conversion. In this work, a NiMo intermetallic compound (IMC) catalyst was prepared based on layered double hydroxides (LDHs) precursors, which displayed prominent catalytic performance for furfural hydrodeoxygenation (HDO) to 2-methylfuran (2-MF) (yield: 99 %) at a rather low hydrogen pressure (0.1 MPa), significantly superior to NiMo alloy, monometallic Ni and other Ni-based catalysts ever reported. CO-IR, STEM, EXAFS and XANES give direct evidences that the atomically-ordered Ni/Mo sites in NiMo IMC determine the uniform bridging-type adsorption mode of C O bond in furfural whilst adsorption of furan ring is extremely suppressed. In situ FT-IR and DFT calculation further substantiate that ordered Ni-Mo bimetallic sites of IMC, in contrast to the random atomic sequence in NiMo alloy, facilitate the activation and cleavage of C OH bond in the intermediate (furfuryl alcohol, FOL), accounting for the production of 2-MF. This work demonstrates the decisive effect of atomically-ordered active sites in IMC catalyst on activation of oxygen-containing functional groups and product selectivity, which can be extended to catalytic upgrading of biomass-derived platform molecules.
研究领域:
催化
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材料科学
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化学工程
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可持续化学
✓ 已验证
产品关联
DOI
高影响因子
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