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The characteristics of bismuth-doped glasses were investigated as colorless ultrabroadband near-infrared gain media. The colorless Bi-doped soda-lime-silicate glass was prepared under controlled redox conditions, and it realized the broadest near-infrared emission of about 600nm in full width at half maximum, centered at 1000nm, under 720nm excitation. The emission band extended toward shorter wavelengths compared with the shortest wavelength for the Bi-doped glass ever reported. The colorless Bi-doped glass developed in this work has a good potential for the broadband gain media for amplifiers and tunable lasers.

The luminescence characteristics of Te-and Bi-doped glasses and glass-ceramics were investigated and the origin of coloration and near infrared luminescence was discussed. The colorations of these glasses and glass-ceramics might be due to the elemental clustering, such as Te 2 Te 2 and Bi 2 Bi 2 . The broad near infrared NIR luminescence can be detected in Te-and Bi-doped glasses and glass-ceramics. The electron spin resonance ESR signal at Ŏ ŋ2.0 was observed in Te-and Bi-doped glasses and glass-ceramics, which exhibit NIR luminescence, and therefore this ESR signal is strongly related to the NIR luminescence. The ESR signal at Ŏ ŋ2.0 might be derived from molecular ions of Te and Bi, Te 2 and Bi 2 . Consequently, it is suggested that the broad NIR luminescence of Te-and Bi-doped glass and glass-ceramics are most likely to be caused by elemental clustering, such as Te 2 Te 2 and Bi 2 Bi 2 .

We have developed a novel and simple protocol for the direct incorporation of a difluoromethyl (CF2H) group into alkenes by visible‐light‐driven photoredox catalysis. The use of fac‐[Ir(ppy)3] (ppy=2‐pyridylphenyl) photocatalyst and shelf‐stable Hu's reagent, N‐tosyl‐S‐difluoromethyl‐S‐phenylsulfoximine, as a CF2H source is the key to success. The well‐designed photoredox system achieves synthesis of not only β‐CF2H‐substituted alcohols but also ethers and an ester from alkenes through solvolytic processes. The present method allows a single‐step and regioselective formation of C(sp3)–CF2H and C(sp3)−O bonds from C=C moiety in alkenes, such as hydroxydifluoromethylation, regardless of terminal or internal alkenes. Moreover, this methodology tolerates a variety of functional groups.

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