Highly dispersed Pd-based pseudo-single atoms in zeolites for hydrogen generation and pollutant disposal
Kai Zhang1, Ning Wang4，*, Yali Meng1, Tianjun Zhang5, Pu Zhao1, Qiming Sun1，2，*, and Jihong Yu3，*
1 Soochow Univ, Coll Chem Chem Engn & Mat Sci, Innovat Ctr Chem Sci, Suzhou 215123, Peoples R China
2 Soochow Univ, Jiangsu Key Lab Adv Negat Carbon Technol, Suzhou 215123, Jiangsu, Peoples R China
3 Jilin Univ, State Key Lab Inorgan Synth & Preparat Chem, Coll Chem, Int Ctr Future Sci, Changchun 130012, Peoples R China
4 Qingdao Univ, Coll Chem & Chem Engn, Inst Sustainable Energy & Resources, Qingdao 266071, Peoples R China
5 Hebei Univ, Coll Chem & Mat Sci, Baoding 071002, Peoples R China
Chem. Sci., 2024, 15, 379
Atomically dispersed metal catalysts with excellent activity and stability are highly desired in heterogeneous catalysis. Herein, we synthesized zeolite-encaged Pd-based pseudo-single atoms via a facile and energy-efficient ligand-protected direct H2 reduction method. Cs-corrected scanning transmission electron microscopy, extended X-ray absorption, and pair distribution function measurements reveal that the metal species are close to atomic-level dispersion and completely confined within the intersectional channels of silicalite-1 (S-1) zeolite with the MFI framework. The Pd@S-1-H exhibits excellent activity and stability in methane combustion reactions with a complete combustion temperature of 390 ℃, and no deactivation is observed even after 100 h on stream. The optimized bimetallic 0.8Pd0.2Ni(OH)2@S-1-H catalyst exhibits an excellent H2 generation rate from FA decomposition without any additives, affording a superhigh turnover frequency up to 9308 h-1 at 333 K, which represents the top activity among all of the best heterogeneous catalysts under similar conditions. Significantly, zeolite-encaged metal catalysts are first used for Cr(Ⅵ) reduction coupled with formic acid (FA) dehydrogenation and show a superhigh turnover number of 2980 mol(Cr2O72-) mol(Pd)-1 at 323 K, surpassing all of the previously reported catalysts. This work demonstrates that zeolite-encaged pseudo-single atom catalysts are promising in efficient hydrogen storage and pollutant disposal applications.
链接：https://pubs.rsc.org/en/content/articlelanding/2024/sc/d3sc05851d
