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Abstract A Rh(II)/Au(I) catalyzed carbene cascade approach for the stereoselective synthesis of diverse spirocarbocycles is described. The cascade reaction involves a rhodium carbene initiatedsp2C−H functionalization followed by a gold catalyzed Conia‐ene cyclization. The cascade reaction accommodates a variety of aryl substituents as well as ring sizes and proceeds with high diastereoselectivity providing access to diverse spirocarbocycles. magnified image
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Ti 2 CT x MXene‐based all‐optical modulator
Abstract MXenes, a new class of 2D transition metal carbides, nitrides, and carbonitrides, have attracted much attention due to their outstanding properties. Here, we report the broadband spatial self‐phase modulation of Ti2CTxMXene nanosheets dispersed in deionized water in the visible to near‐infrared regime, highlighting the broadband nonlinear optical (NLO) response of Ti2CTxMXene. Using ultrafast pulsed laser excitation, the nonlinear refractive indexn2and the third‐order nonlinear susceptibilityof Ti2CTxMXene were measured to be ∼10−13m2/W and ∼ 10−10esu, respectively. Leveraging the large optical nonlinearity of Ti2CTxMXene, an all‐optical modulator in the visible regime was fabricated based on the spatial cross‐phase modulation effect. This work suggests that 2D MXenes are ideal broadband NLO materials with excellent prospects in NLO applications. image
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- Award ID(s):
- 1930881
- PAR ID:
- 10458534
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- InfoMat
- Volume:
- 2
- Issue:
- 3
- ISSN:
- 2567-3165
- Page Range / eLocation ID:
- p. 601-609
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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