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There have been remarkable progresses in manipulating heterogeneous catalysts' nanostructures in the past decade. The concept of single atom alloy (SAA) was firstly proposed in 2012 when researchers successfully stabilized single Pd atoms on the Cu(111) surface. However, earlier work in 2009, which focused on replacing one Au atom with a Pd atom in thiolate protected Au25 nanoclusters, could also be considered as the pioneer work of single atom alloy. Both kinds of single atom alloys exhibited the potential of maximum utilization of scarce elements and attractive catalytic performances. The well‐defined structures of SAA catalysts make accurate modeling possible, which further realizes the rational design of single atom alloy catalysts. In this review, we summarize the research trajectory of single atom alloys as well as recent achievements in this field. We also introduce several commonly adopted characterization methods for SAA catalysts such as scanning tunneling microscopy (STM), temperature programmed reaction (TPR), extended X‐ray absorption fine structure (EXAFS) spectra, matrix assisted laser desorption/ionization mass spectrum (MALDI‐MS) and differential pulse voltammetry (DPV). Through discussing recent progresses in SAA catalysts, we propose that future researches in this filed should be focused on exploring new kinds of metal nanocrystals and controlling the nanostructure of SAA even more precisely. 相似文献
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Lu Chengxun Feng Xinde Wang Chongqing Ll Dechang 《Journal of polymer science. Part A, Polymer chemistry》1980,18(8):2411-2422
Four typical bioactive esters of acrylic monomers, N-p-acryloxybenzoyloxysuccinimides, 3-ac-ryloxy-4-oxo-3,4-dihydro-1,2,3-benzotriazines, N-acryloxy-5-norbornene-2,3-dicarboximides, and I-p-acryloxybenzoyloxybenzotriazoles, were Synthesized and polymerized as reactive polymers. Twelve new monomers were prepared by coupling acrylic acid, methacrylic acid, p-acryloxybenzoic acid, or p-methacryloxybenzoic acid with four N-hydroxy compounds such as N-hydroxysuccinimide (HOSu), 3-hydroxy-4-oxo-3,4-dihydro-1,2,3-benzotriazine (HOObt), N-hydroxy-5-norbornene-2,3-dicarboximide (HONB), and I -hydroxybenzotriazole (HOBT) in the presence of dicyclohexylcarbodimide. All monomers polymerized readily in solution with azobisisobutyronitrile (AIBN) as free radical initiator. The resulting reactive polymers with reactive ? OSu, ? OObt, ? ONB, or ? OBT group on the side chain are equally reactive toward n-butylamine at room temperature in the formation of corresponding polyacrylamides. Reactive polymers were used to immobilizetrypsin. It has been found that poly(N-p-methacryloxybenzoyloxy-5-norbornene-2,3-dicarboximide)-trypsin matrix had high activity around three times that of the poly(N-methacryloxy-5-norbornene-dicarboximide)-trypsin matrix. It is proposed that this activity may be due to the presence of a long spacer arm with a hydrophobic and rigid benzene ring between the ligand and matrix. The reactive poly(N-p-methacryloxybenzoyloxysuccinimide-p-methacryloxybenzoic acid) copolymer was used to immobilize the serum protein. This immobilized protein was a hopeful bioactive solid immunoadsorbent. 相似文献
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D. Charalambidis B. H. Feng C. Fotakis 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1989,14(3):223-227
Photoelectron angular distributions have been measured for the three-photon resonant one-photon ionization, (3+1), of Xe via the 7s[1 1/2]0 1 and 8s[1 1/2]0 1 states. The results are in good agreement with the theoretical predictions of Tang and Lambropoulos [13] for the 8s[1 1/2]0 1, but not for the 7s[1 1/2]0 1 state. Furthermore, the results are compared to those which have been obtained by Blazewicz et al. [1] for the three-photon resonant two-photon ionization, (3+2), of Xe via the 6s[1 1/2]0 1 state. 相似文献