- UV Light Generation and Challenging Photoreactions Enabled by Upconversion in Water
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Sensitized triplet-triplet annihilation (sTTA) is the most promising mechanism for pooling the energy of two visible photons, but its applications in solution were so far limited to organic solvents, with a current maximum of the excited-singlet state energy of 3.6 eV. By combining tailor-made iridium complexes with naphthalenes, we demonstrate blue-light driven upconversion in water with unprecedented singlet-state energies approaching 4 eV. The annihilators have outstanding excited-state reactivities enabling challenging photoreductions driven by sTTA. Specifically, we found that an aryl-bromide bond activation can be achieved with blue photons, and we obtained full conversion for the very energy-demanding decomposition of a persistent ammonium compound as typical water pollutant, not only with a cw laser but also with an LED light source. These results provide the first proof-of-concept for the usage of low-power light sources for challenging reactions employing blue-to-UV upconversion in water and pave the way for the further development of sustainable light-harvesting applications.
- Pfund, Bj?rn,Steffen, Debora M.,Schreier, Mirjam R.,Bertrams, Maria-Sophie,Ye, Chen,B?rjesson, Karl,Wenger, Oliver S.,Kerzig, Christoph
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supporting information
p. 10468 - 10476
(2020/07/27)
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- Highly active PdCu/graphene catalyst for an efficient Suzuki cross-coupling reaction
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A graphene supported Pd-Cu bimetallic catalyst (Pd-Cu/G) has been successfully fabricated by a simple one-pot solvothermal reaction. X-ray diffraction (XRD) analysis as well as morphology characterization demonstrated that Pd-Cu nanoparticles (NPs) are uniformly distributed on the graphene nanosheets. When adopted as the catalyst for the Suzuki cross-coupling reaction, this hybrid exhibited excellent catalytic activity (99.9% conversion) as well as desirable selectivity (99.9%). After recycling five times, the high yield and selectivity were well maintained, illustrating the high durability of this catalyst. This journal is
- M., Xiaojing,Gao, Lingfeng,Weng, Zhentao,Yang, Hua,Sun, Xu
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supporting information
p. 20525 - 20529
(2020/12/28)
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