Huang, K.-C.K.-C.HuangChang, Y.-H.Y.-H.ChangChen, C.-Y.C.-Y.ChenLiu, C.-Y.C.-Y.LiuLin, L.-Y.L.-Y.LinVittal, R.R.VittalWu, C.-G.C.-G.WuLin, K.-F.K.-F.LinHo, K.-C.K.-C.HoKUO-CHUAN HO2018-09-102018-09-102011http://www.scopus.com/inward/record.url?eid=2-s2.0-80755142994&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/363176Nanocomposite, 15-crown-5-functionalized multi-wall carbon nanotubes (denoted as MWCNT-15-C-5) were synthesized and used as an additive along with the ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF 4) in the electrolyte of a dye-sensitized solar cell (DSSC); the pertinent quasi-solid-state DSSC showed a far superior photovoltaic performance than that of a cell with bare EMIBF4 or with MWCNT-added EMIBF 4 (MWCNT/EMIBF4). The heterocyclic structure of the crown ether, 15-C-5, provides its cavities to capture the lithium ions (Li +) in a DSSC, thereby facilitating the dissolution of Li+ and I- in the electrolyte of the cell. This further contributes to an improvement in the exchange reaction of I-/I3- in the electrolyte with EMIBF4. Consequently, the values of short-circuit current density (JSC) and power-conversion efficiency (η) of the DSSC with both EMIBF4 and MWCNT-15-C-5 in its electrolyte showed an increase from 3.23 ± 0.30 to 5.53 ± 0.38 mA cm-2 and from 1.52 ± 0.04 to 2.11 ± 0.10%, respectively, with reference to the values of a DSSC with bare EMIBF 4. Moreover, the at-rest durability of this quasi-solid-state DSSC was found to be unfailing for a period of 1200 h at 100 mW cm-2 illumination. Explanations are substantiated with Raman spectra, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HR-TEM), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS). © 2011 The Royal Society of Chemistry.[SDGs]SDG71-ethyl-3-methylimidazolium tetrafluoroborate; Dye-sensitized solar cells; Exchange reaction; Fourier transform infrared; Heterocyclic structures; Ionic liquid electrolytes; Linear sweep voltammetry; Lithium ions; Photovoltaic performance; Power conversion efficiencies; Quasi-Solid-State dye-sensitized solar cells; Conversion efficiency; Crown ethers; Dissolution; Electrochemical corrosion; Electrochemical impedance spectroscopy; Electrolytes; Ethers; Fourier transforms; High resolution electron microscopy; High resolution transmission electron microscopy; Ion exchange; Ionic liquids; Ions; Lithium; Multiwalled carbon nanotubes (MWCN); Nanocomposites; Photoelectrochemical cells; Photoelectron spectroscopy; Raman spectroscopy; Transmission electron microscopy; X ray photoelectron spectroscopy; Solar cellsjournal article10.1039/c1jm12179k