The metallization of porous silicon (PSi) is generally realized through physical vapor deposition (PVD) or electrochemical processes using aqueous solutions. The former uses a strong vacuum and does not allow for a conformal deposition into the pores. In the latter, the water used as solvent causes oxidation of the silicon during the reduction of the salt precursors. Moreover, as PSi is hydrophobic, the metal penetration into the pores is restricted to the near-surface region. Using a solution of organometallic (OM) precursors in ionic liquid (IL), we have developed an easy and efficient way to fully metallize the pores throughout the several-µm-thick porous Si. This process affords supported metallic nanoparticles characterized by a narrow size distribution. This process is demonstrated for different metals (Pt, Pd, Cu, and Ru) and can probably be extended to other metals. Moreover, as no reducing agent is necessary (the decomposition in an argon atmosphere at 50 °C is fostered by surface silicon hydride groups borne by PSi), the safety and the cost of the process are improved.
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http://dx.doi.org/10.3390/ijms17060876 | DOI Listing |
J Phys Chem Lett
January 2025
Department of Physics, Indian Institute of Technology Delhi (IITD), Delhi 110016, India.
The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are considered to be the most important processes in metal-air batteries and regenerative fuel cell devices. Metal-organic polymers are attracting interest as promising precursors of advanced metal/carbon electrocatalysts because of their hierarchical porous structure along with the integrated metal-carbon framework. We developed carbon-coated CNTs with Ni/Fe and Cu/Fe as active sites.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Faculty of Chemistry, Jagiellonian University in Krakow, Gronostajowa 2, 30-387 Krakow, Poland.
Hydrogen, a sustainable and environmentally friendly fuel, can be obtained through the ethanol steam reforming (ESR) process. The most promising catalysts for this process are those based on non-noble metals such as cobalt. The activity, selectivity, and stability of these catalysts strongly depend on the presence of alkali dopants.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Engineering Research Center of Advanced Rare Earth Materials, Department of Chemistry, Tsinghua University, Beijing 100084, China.
The side reactions accompanying the charging and discharging process, as well as the difficulty in decomposing the discharge product lithium peroxide, have been important issues in the research field of lithium-oxygen batteries for a long time. Here, single atom Ta supported by CoO hollow sphere was designed and synthesized as a cathode catalyst. The single atom Ta forms an electron transport channel through the Ta-O-Co structure to stabilize octahedral Co sites, forming strong adsorption with reaction intermediates and ultimately forming a film-like lithium peroxide that is highly dispersed.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Cardiology, The First People's Hospital of Wenling, Wenling Hospital of Wenzhou Medical University, Wenling, Zhejiang, 317500, China.
Immobilizing enzymes onto solid supports having enhanced catalytic activity and resistance to harsh external conditions is considered as a promising and critical method of broadening enzymatic applications in biosensing, biocatalysis, and biomedical devices; however, it is considerably hampered by limited strategies. Here, a core-shell strategy involving a soft-core hexahistidine metal assembly (HmA) is innovatively developed and characterized with encapsulated enzymes (catalase (CAT), horseradish peroxidase, glucose oxidase (GOx), and cascade enzymes (CAT+GOx)) and hard porous shells (zeolitic imidazolate framework (ZIF), ZIF-8, ZIF-67, ZIF-90, calcium carbonate, and hydroxyapatite). The enzyme-friendly environment provided by the embedded HmA proves beneficial for enhanced catalytic activity, which is particularly effective in preserving fragile enzymes that will have been deactivated without the HmA core during the mineralization of porous shells.
View Article and Find Full Text PDFChem Rec
January 2025
Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia.
In recent times, chemical looping offered a sustainable alternative for upgrading light hydrocarbons into olefins. Olefins are valuable platform chemicals that are utilized for diverse applications. To close the wide shortfall in their global supply, intensified efforts are ongoing to develop on-purpose production technologies.
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