| 1. |
- Chen, Lu, et al.
(författare)
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Anchoring single platinum atoms onto nickel nanoparticles affords highly selective catalysts for lignin conversion
- 2021
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Ingår i: Cell Reports Physical Science. - : Elsevier. - 2666-3864. ; 2:9
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Tidskriftsartikel (refereegranskat)abstract
- Due to the highly complex polyphenolic structure of lignin, depolymerization without a prior chemical treatment is challenging, and new catalysts are required. Atomically dispersed catalysts are able to maximize the atomic efficiency of noble metals, simultaneously providing an alternative strategy to tune the activity and selectivity by alloying with other abundant metal supports. Here, we report a highly active and selective catalyst comprising monodispersed (single) Pt atoms on Ni nanoparticles supported on carbon (denoted as Pt1Ni/C, where Pt-1 represents single Pt atoms), designed for the reductive depolymerization of lignin. Selectivity toward 4-n-propylsyringol and 4-n-propylguaiacol exceeds 90%. The activity and selectivity of the Pt1Ni/C catalyst in the reductive depolymerization of lignin may be attributed to synergistic effects between the Ni nanoparticles and the single Pt atoms.
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| 2. |
- Feng, Feng, et al.
(författare)
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Room-temperature large magnetic-dielectric coupling in new phase anatase VTiO4
- 2013
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Ingår i: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; 49:89, s. 10462-10464
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Tidskriftsartikel (refereegranskat)abstract
- The synthetic new-phase VTiO4, as a new solid solution structure of anatase type, brings a large magnetodielectric ratio (Delta epsilon/epsilon(0)) of 7.2% at 300 K, representing a new simple-oxide structural catalogue exhibiting a room-temperature large magnetic-dielectric effect.
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| 3. |
- Jiang, Jizhong, et al.
(författare)
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Synergistic strain engineering of perovskite single crystals for highly stable and sensitive X-ray detectors with low-bias imaging and monitoring
- 2022
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Ingår i: Nature Photonics. - : Nature Portfolio. - 1749-4885 .- 1749-4893. ; 16:8, s. 575-581
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Tidskriftsartikel (refereegranskat)abstract
- X-ray detectors based on dual-site-doped perovskite single crystals exhibit excellent sensitivity of 2.6 x 10(4) mu C Gy(air)(-1) cm(-2) under a low field of 1 V cm(-1). The detectable dose rate is as low as 7.09 nGy(air) s(-1). The operational stability is beyond half a year. Although three-dimensional metal halide perovskite (ABX(3)) single crystals are promising next-generation materials for radiation detection, state-of-the-art perovskite X-ray detectors include methylammonium as A-site cations, limiting the operational stability. Previous efforts to improve the stability using formamidinium-caesium-alloyed A-site cations usually sacrifice the detection performance because of high trap densities. Here we successfully solve this trade-off between stability and detection performance by synergistic composition engineering, where we include A-site alloys to decrease the trap density and B-site dopants to release the microstrain induced by A-site alloying. As such, we develop high-performance perovskite X-ray detectors with excellent stability. Our X-ray detectors exhibit high sensitivity of (2.6 +/- 0.1) x 10(4) mu C Gy(air)(-1) cm(-2) under 1 V cm(-1) and ultralow limit of detection of 7.09 nGy(air) s(-1). In addition, they feature long-term operational stability over half a year and impressive thermal stability up to 125 degrees C. We further demonstrate the promise of our perovskite X-ray detectors for low-bias portable applications with high-quality X-ray imaging and monitoring prototypes.
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| 4. |
- Xiong, Min, et al.
(författare)
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Tailoring Phase Purity in the 2D/3D Perovskite Heterostructures Using Lattice Mismatch
- 2022
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Ingår i: ACS Energy Letters. - : AMER CHEMICAL SOC. - 2380-8195. ; 7:1, s. 550-559
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Tidskriftsartikel (refereegranskat)abstract
- Although the fabrication of two-dimensional (2D)/three-dimensional (3D) halide perovskite heterostructures has been employed to balance the long-term stability and high efficiency of perovskite solar cells, the formation of metastable quasi-2D perovskites remains the most serious challenge. Here, we demonstrate that large lattice mismatch derived from halide and cation differences between 2D and 3D perovskites are key to avoiding the formation of unintended 2D phases in the preparation of 2D/3D bulk heterostructure because the phase transformation becomes less thermodynamically favorable. Specifically, by employing chloride 2D perovskite (PYA)(2) PbCl4 (PYA = propargylammonium) crystals into a 3D precursor solution, we achieve a phase-pure 2D/3D heterojunction with clean type-I band alignment, which exhibits greatly reduced charge recombination. Furthermore, the incorporation of alkyne perovskites is also shown to suppress iodine diffusion and formation due to their exceptional iodine capture capacity. The resultant 2D/3D heterostructured devices exhibited enhanced efficiencies and stabilities compared with their 3D counterparts.
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