| 1. |
- Jia, Xue, et al.
(författare)
-
CsPb(IxBr1-x)(3) solar cells
- 2019
-
Ingår i: Science Bulletin. - : ELSEVIER. - 2095-9273. ; 64:20, s. 1532-1539
-
Tidskriftsartikel (refereegranskat)abstract
- Owing to its nice performance, low cost, and simple solution-processing, organic-inorganic hybrid perovskite solar cell (PSC) becomes a promising candidate for next-generation high-efficiency solar cells. The power conversion efficiency (PCE) has boosted from 3.8% to 25.2% over the past ten years. Despite the rapid progress in PCE, the device stability is a key issue that impedes the commercialization of PSCs. Recently, all-inorganic cesium lead halide perovskites have attracted much attention due to their better stability compared with their organic-inorganic counterpart. In this progress report, we summarize the properties of CsPb(IxBr1-x)(3) and their applications in solar cells. The current challenges and corresponding solutions are discussed. Finally, we share our perspectives on CsPb(IxBr1-x)(3) solar cells and outline possible directions to further improve the device performance. (C) 2019 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.
|
|
| 2. |
- Cao, Guanyue, et al.
(författare)
-
Porphyrindiene-Based Tandem Diels-Alder Reaction for Preparing Low-Symmetry pi-Extended Porphyrins with Push-Pull Skeletons
- 2022
-
Ingår i: Journal of Organic Chemistry. - : AMER CHEMICAL SOC. - 0022-3263 .- 1520-6904. ; 87:14, s. 9001-9010
-
Tidskriftsartikel (refereegranskat)abstract
- Tandem Diels-Alder reactions of masked porphyrindienes (i.e., sulfolenoporphyrins) with benzoquinones and stilbenes, followed by aromatization, have been developed to load porphyrin with mixed annulation units (i.e., terphenyl and naphthoquinone), furnishing the low-symmetry pi-extended porphyrins (DxAy) with push-pull skeletons. All low-symmetrical chromophores display panchromatic absorption spectra, which look like a spectral combination of symmetrical congeners (D4/A4) in a certain ratio. Among them, tD2A2 with trans-arrangement of push/pull units possesses the largest maximum centered at 766 nm with the onset around 900 nm. The fusion of the electron-deficient naphthoquinone moiety on the porphyrin core results in the approximately quantitative regulation of the E-ox1 and HOMOs (i.e., 0.10-0.13 V increase for the E-ox1 and 0.14-0.16 eV decrease for the HOMOs per naphthoquinone unit). In brief, this work provides a new way to construct low-symmetry pi-extended porphyrins with tunable properties resorting to the ratios and locations of the annulated push-pull units.
|
|
| 3. |
- Li, Youbing, et al.
(författare)
-
A general Lewis acidic etching route for preparing MXenes with enhanced electrochemical performance in non-aqueous electrolyte
- 2020
-
Ingår i: Nature Materials. - : NATURE PUBLISHING GROUP. - 1476-1122 .- 1476-4660. ; 19:8, s. 894-899
-
Tidskriftsartikel (refereegranskat)abstract
- Two-dimensional transition metal carbides and nitrides, known as MXenes, are currently considered as energy storage materials. A generic Lewis acidic etching route for preparing high-rate negative-electrode MXenes with enhanced electrochemical performance in non-aqueous electrolyte is now proposed. Two-dimensional carbides and nitrides of transition metals, known as MXenes, are a fast-growing family of materials that have attracted attention as energy storage materials. MXenes are mainly prepared from Al-containing MAX phases (where A = Al) by Al dissolution in F-containing solution; most other MAX phases have not been explored. Here a redox-controlled A-site etching of MAX phases in Lewis acidic melts is proposed and validated by the synthesis of various MXenes from unconventional MAX-phase precursors with A elements Si, Zn and Ga. A negative electrode of Ti3C2 MXene material obtained through this molten salt synthesis method delivers a Li+ storage capacity of up to 738 C g(-1) (205 mAh g(-1)) with high charge-discharge rate and a pseudocapacitive-like electrochemical signature in 1 M LiPF6 carbonate-based electrolyte. MXenes prepared via this molten salt synthesis route may prove suitable for use as high-rate negative-electrode materials for electrochemical energy storage applications.
|
|
| 4. |
- Liu, Mingren, et al.
(författare)
-
Ion Bridging by Carbon Dioxide Facilitates Electrochemical Energy Storage at Charged Carbon–Ionic–Liquid Interfaces
- 2023
-
Ingår i: Advanced Energy Materials. - 1614-6832 .- 1614-6840. ; 13:21
-
Tidskriftsartikel (refereegranskat)abstract
- Solvent free ionic liquid (IL) electrolytes facilitate high-voltage supercapacitors with enhanced energy density, but their complex ion arrangement and through that the electrochemical properties, are limited by strong Coulombic ordering in the bulk state and like-charged ion repulsion at electrified interfaces. Herein, a unique interfacial phenomenon resulting from the presence of carbon dioxide loaded in 1-Ethyl-3-methylimidazoliumtetrafluorborate electrolyte that simultaneously couples to IL ions and nitrogen-doped carbonaceous electrode is reported. The adsorbed CO2 molecule polarizes and mitigates the electrostatic repulsion among like-charged ions near the electrified interface, leading to an ion “bridge effect” with increased interfacial ionic density and significantly enhanced charge storage capability. The unpolarized CO2 possessing a large quadrupole moment further reduces ion coupling, resulting in higher conductivity of the bulk IL and improved rate capability of the supercapacitor. This work demonstrates polarization-controlled like-charge attraction at IL–electrode–gas three-phase boundaries, providing insights into manipulating complex interfacial ion ordering with small polar molecule mediators.
|
|
| 5. |
- Torstensen, Jonathan Ø, et al.
(författare)
-
Swelling and Free-Volume Characteristics of TEMPO-Oxidized Cellulose Nanofibril Films.
- 2018
-
Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 19:3, s. 1016-1025
-
Tidskriftsartikel (refereegranskat)abstract
- Cellulose nanofibrils (CNFs) are becoming increasingly ubiquitous in diverse technologies requiring sustainable nanoscale species to form or modify films. The objective of the present study is to investigate the swelling behavior and accompanying free volume of self-standing TEMPO-oxidized (TO) CNF films in the presence of water vapor. For this purpose, we have performed time-resolved swelling experiments on films, prepared according to different experimental protocols, at 90% relative humidity (RH) and ambient temperature. Corresponding free-volume characteristics are elucidated by positron annihilation lifetime spectroscopy (PALS) conducted at ambient temperature and several RH levels. Increasing the drying temperature of the films (from ambient to 50 °C) is observed to promote an increase in film density, which serves to reduce bulk swelling. These elevated drying temperatures likewise cause the free-volume pore size measured by PALS to decrease, while the corresponding total free-volume fraction remains nearly constant. Similarly, dispersion of TO-CNF into aqueous suspensions by ultrasonication prior to film formation increases both the total free-volume fraction and pore size but reduces the size of individual nanofibrils with little net change in bulk swelling. The swelling and concurrent free-volume measurements reported here generally reveal an increase in the free volume of TO-CNF films with increasing RH.
|
|
