@article{GhaniOpitzPingeletal.2015,
  author    = {Ghani, Fatemeh and Opitz, Andreas and Pingel, Patrick and Heimel, Georg and Salzmann, Ingo and Frisch, Johannes and Neher, Dieter and Tsami, Argiri and Scherf, Ullrich and Koch, Norbert},
  title     = {Charge Transfer in and Conductivity of Molecularly Doped Thiophene-Based Copolymers},
  series = {Journal of polymer science : B, Polymer physics},
  volume    = {53},
  journal   = {Journal of polymer science : B, Polymer physics},
  number    = {1},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0887-6266},
  doi       = {10.1002/polb.23631},
  pages     = {58 -- 63},
  year      = {2015},
  abstract  = {The electrical conductivity of organic semiconductors can be enhanced by orders of magnitude via doping with strong molecular electron acceptors or donors. Ground-state integer charge transfer and charge-transfer complex formation between organic semiconductors and molecular dopants have been suggested as the microscopic mechanisms causing these profound changes in electrical materials properties. Here, we study charge-transfer interactions between the common molecular p-dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane and a systematic series of thiophene-based copolymers by a combination of spectroscopic techniques and electrical measurements. Subtle variations in chemical structure are seen to significantly impact the nature of the charge-transfer species and the efficiency of the doping process, underlining the need for a more detailed understanding of the microscopic doping mechanism in organic semiconductors to reliably guide targeted chemical design.},
  language  = {en}
}
@article{ZapataArteagaMarinaZuoetal.2022,
  author    = {Zapata-Arteaga, Osnat and Marina, Sara and Zuo, Guangzheng and Xu, Kai and D{\"o}rling, Bernhard and Alberto P{\´e}rez, Luis and Sebasti{\´a}n Reparaz, Juan and Mart{\´i}n, Jaime and Kemerink, Martijn and Campoy-Quiles, Mariano},
  title     = {Design rules for polymer blends with high thermoelectric performance},
  series = {Advanced energy materials},
  volume    = {12},
  journal   = {Advanced energy materials},
  number    = {19},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1614-6832},
  doi       = {10.1002/aenm.202104076},
  pages     = {11},
  year      = {2022},
  abstract  = {A combinatorial study of the effect of in-mixing of various guests on the thermoelectric properties of the host workhorse polymer poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT) is presented. Specifically, the composition and thickness for doped films of PBTTT blended with different polymers are varied. Some blends at guest weight fractions around 10-15\% exhibit up to a fivefold increase in power factor compared to the reference material, leading to zT values around 0.1. Spectroscopic analysis of the charge-transfer species, structural characterization using grazing-incidence wide-angle X-ray scattering, differential scanning calorimetry, Raman, and atomic force microscopy, and Monte Carlo simulations are employed to determine that the key to improved performance is for the guest to promote long-range electrical connectivity and low disorder, together with similar highest occupied molecular orbital levels for both materials in order to ensure electronic connectivity are combined.},
  language  = {en}
}
@article{LeCorreStolterfohtPerdigonToroetal.2019,
  author    = {Le Corre, Vincent M. and Stolterfoht, Martin and Perdig{\´o}n-Toro, Lorena and Feuerstein, Markus and Wolff, Christian Michael and Gil-Escrig, Lidon and Bolink, Henk J. and Neher, Dieter and Koster, L. Jan Anton},
  title     = {Charge Transport Layers Limiting the Efficiency of Perovskite Solar Cells: How To Optimize Conductivity, Doping, and Thickness},
  series = {ACS Applied Energy Materials},
  volume    = {2},
  journal   = {ACS Applied Energy Materials},
  number    = {9},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {2574-0962},
  doi       = {10.1021/acsaem.9b00856},
  pages     = {6280 -- 6287},
  year      = {2019},
  abstract  = {Perovskite solar cells (PSCs) are one of the main research topics of the photovoltaic community; with efficiencies now reaching up to 24\%, PSCs are on the way to catching up with classical inorganic solar cells. However, PSCs have not yet reached their full potential. In fact, their efficiency is still limited by nonradiative recombination, mainly via trap-states and by losses due to the poor transport properties of the commonly used transport layers (TLs). Indeed, state-of-the-art TLs (especially if organic) suffer from rather low mobilities, typically within 10(-5) and 10(-2) cm(-2) V-1 s(-1), when compared to the high mobilities, 1-10 cm(-2) V-1 s(-1), measured for perovskites. This work presents a comprehensive analysis of the effect of the mobility, thickness, and doping density of the transport layers based on combined experimental and modeling results of two sets of devices made of a solution-processed high-performing triple-cation (PCE approximate to 20\%). The results are also cross-checked on vacuum-processed MAPbI(3) devices. From this analysis, general guidelines on how to optimize a TL are introduced and especially a new and simple formula to easily calculate the amount of doping necessary to counterbalance the low mobility of the TLs.},
  language  = {en}
}