A supported Pd-Au (Au 7wt%) membrane was produced by electroless plating deposition. Permeation tests were performed with pure gas (H₂, H₂, N₂, CO₂, CH₄) for long time operation. After around 400 h under testing, the composite Pd-Au membrane achieved steady state condition, with an H₂/N₂ ideal selectivity of around 500 at 420 °C and 50 kPa as transmembrane pressure, remaining stable up to 1100 h under operation. Afterwards, the membrane was allocated in a membrane reactor module for methane steam reforming reaction tests. As a preliminary application, at 420 °C, 300 kPa of reaction pressure, space velocity of 4100 h(-1), 40% methane conversion and 35% hydrogen recovery were reached using a commercial Ni/Al₂O₃ catalyst. Unfortunately, a severe coke deposition affected irreversibly the composite membrane, determining the loss of the hydrogen permeation characteristics of the supported Pd-Au membrane.
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http://dx.doi.org/10.3390/molecules21050581 | DOI Listing |
RSC Adv
September 2024
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University Nanjing 210096 Jiangsu China
Angew Chem Int Ed Engl
January 2025
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.
Metal clusters, due to their small dimensions, contain a high proportion of surface atoms, thus possessing a significantly improved catalytic activity compared with their bulk counterparts and nanoparticles. Defective and modified carbon supports are effective in stabilizing metal clusters, however, the synthesis of isolated metal clusters still requires multiple steps and harsh conditions. Herein, we develop a C fullerene-driven spontaneous metal deposition process, where C serves as both a reductant and an anchor, to achieve uniform metal (Rh, Ir, Pt, Pd, Au and Ru) clusters without the need for any defects or functional groups on C.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2023
Deep Space Exploration Laboratory/School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China.
The kinetics and pathway of most catalyzed reactions depend on the existence of interface, which makes the precise construction of highly active single-atom sites at the reaction interface a desirable goal. Herein, we propose a thermal printing strategy that not only arranges metal atoms at the silica and carbon layer interface but also stabilizes them by strong coordination. Just like the typesetting of Chinese characters on paper, this method relies on the controlled migration of movable nanoparticles between two contact substrates and the simultaneous emission of atoms from the nanoparticle surface at high temperatures.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2023
State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 200237, Shanghai, China.
The electrocatalytic sulfur reduction reaction (SRR) would allow the production of renewable high-capacity rechargeable lithium-sulfur (Li-S) batteries using sustainable and nontoxic elemental sulfur as a cathode material, but its slow reaction rate causes a serious shuttle effect and dramatically reduces the capacity. We found that a catalyst composed of Pd nanoparticles supported by ordered mesoporous carbon (Pd/OMC) had a high reaction rate in the SRR, and a Li-S battery assembled with this catalyst had a low shuttle constant of 0.031 h and a high-rate performance with a specific capacity of 1527 mAh g at 0.
View Article and Find Full Text PDFNanoscale
October 2023
Department of Chemistry, Center for High Entropy Alloy Catalysis, University of Copenhagen, 2100 Copenhagen, Denmark.
The dissolution of nanoparticles under corrosive environments represents one of the main issues in electrochemical processes. Here, a model for alloying and protecting nanoparticles from corrosion with an anti-corrosive element ( Au) is proposed based on the hypothesis that under-coordinated atoms are the first atoms to dissolve. The model considers the dissolution of atoms with coordination number ≤6 on A-B nanoparticles with different sizes, shapes, chemical compositions, and exposed crystallographic orientations.
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