TY  - JOUR
A1  - Shoaee, Safa
A1  - Sanna, Anna Laura
A1  - Sforazzini, Giuseppe
T1  - Elucidating charge generation in green-solvent processed organic solar cells
JF  - Molecules : a journal of synthetic chemistry and natural product chemistry / Molecular Diversity Preservation International
N2  - Organic solar cells have the potential to become the cheapest form of electricity. Rapid increase in the power conversion efficiency of organic solar cells (OSCs) has been achieved with the development of non-fullerene small-molecule acceptors. Next generation photovoltaics based upon environmentally benign "green solvent" processing of organic semiconductors promise a step-change in the adaptability and versatility of solar technologies and promote sustainable development. However, high-performing OSCs are still processed by halogenated (non-environmentally friendly) solvents, so hindering their large-scale manufacture. In this perspective, we discuss the recent progress in developing highly efficient OSCs processed from eco-compatible solvents, and highlight research challenges that should be addressed for the future development of high power conversion efficiencies devices.
KW  - organic solar cells
KW  - green solvents
KW  - non-halogenated solvents
KW  - exaction
KW  - diffusion
KW  - photoluminescence quenching
Y1  - 2021
U6  - https://doi.org/10.3390/molecules26247439
SN  - 1420-3049
VL  - 26
IS  - 24
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Koopman, Wouter-Willem Adriaan
A1  - Natali, Marco
A1  - Donati, Giovanni P.
A1  - Muccini, Michele
A1  - Toffanin, Stefano
T1  - Charge-exciton interaction rate in organic field-effect transistors by means of transient photoluminescence electromodulated spectroscopy
JF  - ACS photonics
N2  - Organic light-emitting transistors (OLETs) offer a huge potential for the design of highly integrated multifunctional optoelectronic systems and of intense nano scale light sources, such as the long-searched-for electrically pumped organic laser. In order to fulfill these promises, the efficiency and brightness of the current state-of-the-art devices have to be increased significantly. The dominating quenching process limiting the external quantum efficiency in OLETs is charge-exciton interaction. A comprehensive understanding of this quenching process is therefore of paramount importance. The present article reports a systematic investigation of charge-exciton interaction in organic transistors employing time resolved photoluminescence electro-modulation (PLEM) spectroscopy on the picosecond time scale. The results show that the injected charges reduce the exciton radiative recombination in two ways: (i) charges may prevent the generation of excitons and (ii) charges activate a further nonradiative channel for the exciton decay. Moreover, the transient PLEM measurements clearly reveal that not only trapped charges, as already reported in literature, but rather the entire injected charge density contributes to the quenching of the exciton population.
KW  - photoluminescence quenching
KW  - charge density
KW  - exciton dynamics
KW  - organic
KW  - field-effect transistor
KW  - light emission
KW  - optical spectroscopy
Y1  - 2017
U6  - https://doi.org/10.1021/acsphotonics.6b00573
SN  - 2330-4022
VL  - 4
IS  - 2
SP  - 282
EP  - 291
PB  - American Chemical Society
CY  - Washington, DC
ER  -