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Ge4+ substitution into the recently discovered superionic conductor Li7Si2S7I is demonstrated by synthesis of Li7Si2–xGexS7I, where x≤1.2. The anion packing and tetrahedral silicon location of Li7Si2S7I are retained upon substitution. Single crystal X‐ray diffraction shows that substitution of larger Ge4+ for Si4+ expands the unit cell volume and further increases Li+ site disorder, such that Li7Si0.88Ge1.12S7I has one Li+ site more (sixteen in total) than Li7Si2S7I. The ionic conductivity of Li7Si0.8Ge1.2S7I (x=1.2) at 303 K is 1.02(3)×10−2 S cm−1 with low activation energies for Li+ transport demonstrated over a wide temperature range by AC impedance and 7Li NMR spectroscopy. All sixteen Li+ sites remain occupied to temperatures as low as 30 K in Li7Si0.88Ge1.12S7I as a result of the structural expansion. This differs from Li7Si2S7I, where the partial Li+ site ordering observed below room temperature reduces the ionic conductivity. The suppression of Li+ site depopulation by Ge4+ substitution retains the high mobility to temperatures as low as 200 K, yielding low temperature performance comparable with state‐of‐the‐art Li+ ion conducting materials. [ABSTRACT FROM AUTHOR]

Byline: Kay Kyeongju Seo, Andy Curran, Nancy A. Jennings, Chris M. Collins Podcasting is becoming an important content delivery strategy, shaping new mobile learning communities both in live classrooms and in distance learning environments. Students have shown favourable responses to podcasts and some universities now offer formal podcasting initiatives or programs to assist faculty in using the technology. As podcasting is becoming more popular, there is a need to accurately assess the educational potential of the technology and develop effective strategies for supporting a podcast community. This article explores recent developments in podcasting, reports on a recent survey of 137 US students' perceptions of the technology and describes existing support services for podcasting in 50 US universities.