Reducing environmental impact is a key challenge for perovskite optoelectronics, as most high-performance devices are based on potentially toxic lead-halide perovskites. For photovoltaic solar cells, tin-lead (Sn–Pb) perovskite materials provide a promising solution for reducing toxicity. However, Sn–Pb perovskites typically exhibit low luminescence efficiencies, and are not ideal for light-emitting applications. Here we demonstrate highly luminescent germanium-lead (Ge–Pb) perovskite films with photoluminescence quantum efficiencies (PLQEs) of up to ~71%, showing a considerable relative improvement of ~34% over similarly prepared Ge-free, Pb-based perovskite films. In our initial demonstration of Ge–Pb perovskite LEDs, we achieve external quantum efficiencies (EQEs) of up to ~13.1% at high brightness (~1900 cd m−2), a step forward for reduced-toxicity perovskite LEDs. Our findings offer a new solution for developing eco-friendly light-emitting technologies based on perovskite semiconductors.

Biodiesel has gained significant attention as an alternative to petroleum diesel. Currently, there is an increasing interest in obtaining microbial oils from oleaginous micro‐organisms for biodiesel production. In the accumulation of microbial oils, carbon substrate constitutes a major portion of the cost. Accordingly, significant efforts have been made to explore suitable carbon sources, and to investigate their effects on cell growth as well as lipid synthesis. This paper reviews the current trend of using various carbon sources for microbial oils production, including carbon dioxide, conventional saccharides, energy crops, C2 compounds, lignocellulosic biomass, and glycerol. The strategies for enhancement of microbial oils production are further discussed. Finally, the constraints and perspectives of using microbial oils for biodiesel production are also highlighted. © 2012 Society of Chemical Industry and John Wiley & Sons Ltd

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