Fullerene derivatives with increased dielectric constants

Abstract

The invention of new organic materials with high dielectric constants is of extreme importance for the development of organic-based devices such as organic solar cells. We report on a synthetic way to increase the dielectric constant of fullerene derivatives. It is demonstrated that introducing triethylene glycol monoethyl ether (teg) side chains into fulleropyrrolidines increases the dielectric constant by ~46 percent without devaluation of optical properties, electron mobility and the energy level of the compound.

Promising Strategy To Improve Charge Separation in Organic Photovoltaics: Installing Permanent Dipoles in PCBM Analogues

“…This work illustrates using a multidisciplinary approach that the proposed strategy 25,[28][29][30] for improving charge separation in OPV, i.e., installing polarisable side-groups and permanent dipoles in polymers and PCBM analogues, is a promising one. The good correspondence between experimentally and theoretically determined molecular properties of the studied PCBM analogues indicates that the theoretical analysis of the embedding effects of these molecules gives a reliable expectation for their influence on the charge separation process at a microscopic scale in a real device.…”

“…30 Studies of the performance of OPV devices containing donor and acceptor molecules functionalised with TEG side-chains [29][30] are currently in progress. Donaghey et al 31 report some encouraging outcomes of initial OPV device testing.…”

Defect Dynamics in Proton Irradiated CH3NH3PbI3 Perovskite Solar Cells

“…CPCBM= εPCBMε0Α/dPCBM is the geometric capacitance of the PCBM film (dPCBM = 45 nm) and CP = εPε0Α/dP is the geometric capacitance of the perovskite film (dP = 350 nm). The dielectric constant of PCBM amounts to εPCBM = 3.9 [21] and the dielectric constant of perovskite εP can be calculated from the following equation:…”

Efficient Perovskite Solar Cells over a Broad Temperature Window: The Role of the Charge Carrier Extraction

“…When the more conductive fulleropyrrolidine with a triethylene glycol monoethyl ether side chain (PTEG-1) [16] is used as EEL, the charge extraction is surprisingly efficient over a broad temperature range. The J SC (≈21.2 mA cm −2 ) and FF (≈0.8) stay relatively constant down to 140 K. Moreover, this is accompanied by an increase in open circuit voltage V OC (from 0.93 to 1.08 V), which result in an overall increase of the PCE from 16.03% (295 K) to 18.16% (180 K), followed by a slight decrease to 17.61% at 140 K. Furthermore, the electron transport of the [60]PCBM layer is improved by n-doping with poly [(9,9-bis(3′-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) and LiF (upon thermal treatment).…”