RESUMO
In this work, we analytically derive the transmission spectra of the seven-core fiber (SCF) with a phase mismatch between the center core and outer cores based on the mode coupling theory. We also establish the wavelength shift as a function of temperature and ambient refractive index (RI) using approximations and differentiation techniques. Our results reveal the opposite effects of temperature and ambient RI on the wavelength shift of the SCF transmission spectrum. The theoretical conclusions are confirmed by our experiments on the behavior of SCF transmission spectra under various temperature and ambient RI conditions.
RESUMO
Correction for 'Tunable deep-blue luminescence from ball-milled chlorine-rich Csx(NH4)1-xPbCl2Br nanocrystals by ammonium modulation' by Hongfei Xiao et al., Chem. Commun., 2022, 58, 3827-3830, DOI: 10.1039/D1CC07125D.
RESUMO
For the first time, a novel class of deep-blue (DB)-emitting Csx(NH4)1-xPbCl2Br (0.3 ≤ x ≤ 1) perovskite nanocrystals (PNCs) were prepared by a facile ligand-assisted one-step ball milling method. The resulted PNCs are characterized by high chlorine content (66.7%) and excellent color purity. Their photoluminescence position can be finely modulated from 434 nm to 447 nm, which extends notably beyond the current Rec. 2020 color standard, by the NH4+ content. Among them, Cs0.3(NH4)0.7PbCl2Br shows the highest quantum yield close to 40%. The PNCs exhibit high phase and optical stability under ambient conditions and UV light according to the NH4+ content. This work offers a new avenue to produce DB perovskites for future full-color displays and optoelectronics.
RESUMO
There has been a growing interest in the design and synthesis of non-fullerene acceptors for organic solar cells that may overcome the drawbacks of the traditional fullerene-based acceptors. Herein, two novel push-pull (acceptor-donor-acceptor) type small-molecule acceptors, that is, ITDI and CDTDI, with indenothiophene and cyclopentadithiophene as the core units and 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (INCN) as the end-capping units, are designed and synthesized for non-fullerene polymer solar cells (PSCs). After device optimization, PSCs based on ITDI exhibit good device performance with a power conversion efficiency (PCE) as high as 8.00%, outperforming the CDTDI-based counterparts fabricated under identical condition (2.75% PCE). We further discuss the performance of these non-fullerene PSCs by correlating the energy level and carrier mobility with the core of non-fullerene acceptors. These results demonstrate that indenothiophene is a promising electron-donating core for high-performance non-fullerene small-molecule acceptors.