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The modified predictive model, which incorporated size of SLN metastasis, improved predictive accuracy, although further testing on an independent data set is desirable.

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Fullerenes have attracted considerable interest as an electron-transporting layer in perovskite solar cells. Fullerene-based perovskite solar cells produce no hysteresis and do not require high-temperature annealing. However, high power conversion efficiency has been only achieved when the fullerene layer is thermally evaporated, which is an expensive process. In this work, the limitations of a solution-processed fullerene layer have been identified as high crystallinity and the presence of remnant solvents, in contrast to a thermally deposited C60 film, which has low crystallinity and no remaining solvents. As a solution to these problems, a mixed C60 and C70 solution-processed film, which exhibits low crystallinity, is proposed as an electron-transporting layer. The mixed-fullerene-based devices produce power conversion efficiencies as high as that of the thermally evaporated C60-based device (16.7%) owing to improved fill factor and open-circuit voltage. In addition, by vacuum-drying the mixed fullerene film, the power conversion efficiency of the solution-processed perovskite solar cells is further improved to 18.0%. This improvement originates from the enhanced transmittance and charge transport by removing the solvent effect. This simple and low-cost method can be easily used in any type of solar cells with fullerene as the electron-transporting layer.

N,NЈ-Di-tert-butyl-1,4-diaza-1,3-butadiene reacts with elemental lithium under reduction to give a dilithium salt, which forms with fluorosilanes the diazasilacyclopentenes 1Ϫ4

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A polymer precursor based on phlorogucinol-salicyaldehyde-melamine (PSM@silica) has been synthesized using pluronic P123 and tetratethyl orthosilane as the structure directing matrix. The polymer has been pyrolyzed under nitrogen flow at different temperatures from 700 to 1000 °C to obtain the corresponding carbons, CPSM-700, CPSM-800, CPSM-900, and CPSM-1000. Carbonization temperature is found to play an important role on the morphology, heteroatom content, and surface area of the products. The samples have been characterized by various techniques such as powder X-ray diffraction, nitrogen adsorption/desorption, scanning electron microscopy and X-ray photoelectron spectroscopy studies. The spherical carbon particles of micron meter diameters with high surface area and heteroatom doping (O, N) make them potential candidates for electrochemical applications. Detailed electrochemical studies have been carried out for all the samples by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) in 1 M H2SO4 electrolyte. It is found that CPSM-900 shows the best results with specific capacitance of 400 F·g–1 at 0.6 A·g–1 current density. Remarkably, at high current density of 12.16 A·g–1 it still retains a very high value of 270 F·g–1. Its well-defined spherical morphology (ca. 1.16 μm diameters), high Brunauer–Emmett–Teller (BET) surface area (712 m2·g–1), and nitrogen content of ca. 2.61% are responsible for its superior performance. It shows high specific energy density and a power density of 44.92 Wh·kg–1 and 274.116 W·kg–1, respectively, at a current density of 0.6 A·g–1. The corresponding values are maintained up to 30.37 Wh·kg–1 and 5461.5 W·kg–1 at 12.16 A·g–1. The material is highly stable with no loss of specific capacitance up to 5000 cycles at 6.21 A·g–1 current density.