Lead halide perovskite nanocrystals (PNCs) have very recently emerged as promising emitters for their superior optoelectronic properties.

A new technique for wall conditioning that will be especially useful for future larger superconducting tokamaks, such as ITER, has been successfully developed and encouraging results have been obtained. Solid carborane powder, which is non-toxic and non-explosive, was used. Pulsed RF plasma was produced by a non-Faraday shielding RF antenna with RF power of 10 kW. The ion temperature was about 2 keV with a toroidal magnetic field of 1.8 T and a pressure of 3 × 10-1 Pa. Energetic ions broke up the carborane molecules, and the resulting boron ions struck and were deposited on the first wall. In comparison with glow discharge cleaning boronization, the B/C coating film shows higher adhesion, more uniformity and longer lifetime during plasma discharges. The plasma performance was improved after ICRF boronization.

One of the challenges for the commercialization of polymer solar cells (PSCs) is the difficulty in fabricating a homogeneous and pinhole-free, thin active layer through a largescale, high-throughput, roll-to-toll manufacturing process. On the other hand, thick active layers in current PSCs generally result in low power conversion efficiency (PCE). Here, we reported the effect of active layer thickness on the performance of the PSC device based on the state-of-the-art blends of poly [4,8-bis(5-(2ethylhexyl)]-phenyl C 71 butyric acid methyl ester (PC 71 BM). The results showed that although the short-circuit current density (J SC ) was increased in the device with thicker active layer the PCE was decreased due to the drastically declined fill factor (FF), which offset the improved light absorption from using thicker films. Optical modeling using the transfer matrix method (TMM) and analysis of the fitted Shockley diode equation of illuminated current density−voltage (J−V) characteristics indicated that the decrease of FF for thicker PTB7-Th:PC 71 BM solar cells was ascribed to the inefficient charge carrier transport and collection, which resulted from relatively low electron mobility and the increased interface defect states. Based on these results, the devices with higher PC 71 BM content were fabricated to facilitate the electron transport, which allowed an overall increase of the efficiency to 8.15% for the device with a 270 nm thick active layer due to the significantly improved FF.

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