Graphene nanoplatelet doping of P3HT:PCBM photoactive layer of bulk heterojunction organic solar cells for enhancing performance

Abstract

Hybrid organic photovoltaic (OPV) cells based on conjugated polymers photoactive materials are promising candidates for flexible, high-performance and low-cost energy sources owing to their inexpensive materials, cost-effective processing, and ease of fabrication by simple solution processes. However, the modest PV performance obtained to date -in particular the low power conversion efficiency (PCE)- has impeded the large scale deployment of OPV cells. The low PCE in OPV solar cells has been mainly attributed to low carrier mobility, which is closely correlated to the transport diffusion length of the charge carriers within the photoactive layers. The 2D graphene material can be an excellent candidate for assisting the charge transport improvement in the active layer of OPV cells due to its huge carrier mobility, thermal and chemical stability, and its compatibility with the solution process. In this work, we report on the improvement of optoelectronic properties and photovoltaic performance of graphene nanoplatelets (GNP) doped P3HT:PCBM photoactive blended layers, integrated into a bulk heterojunction (BHJ) organic photovoltaic based device, using PEDOT:PSS on ITO/glass substrate. First, the light absorption capacity was observed to increase with respect to the GNP contents while the photoluminescence showed a clear quenching, indicating electrons transfer between the graphene sheets and the polymeric matrix. Then, the incorporation of GNP into the BHJ active layer has resulted in enhanced PV performance with respect to a reference cell, and the best PV performances were obtained with 3 wt. % of GNP loading, with an open-circuit voltage of 1.24 V, a short-circuit current density value of 6.18 mA/cm2, a fill factor of 47.12 %, and a power conversion efficiency of about 3.61 %. We believe that the obtained results contribute to the development of organic photovoltaic devices and to the understanding of the impact of sp2-bonded carbon therein.

Tuning the electrical and morphological characteristics of PEDOT:PSS filmsthrough mixed cosolvent addition and performance of their polymer solar cells

“…The control device produced with a nondoped PEDOT:PSS layer showed a PCE of 2.25% with a J sc of 12.15 mA cm −2 , a V oc of 0.455 V, and a FF of 40.7%. This PCE is comparable to results reported in the literature, which can be seen in Table 2 [31][32][33][34][35]. In comparison to the control device, all devices fabricated with a doped PEDOT:PSS layer yielded superior PCE thanks to enhanced V oc and J sc values, while the FF values were mostly unchanged.…”

Preparation of Nanocomposite-Based High Performance Organic Field Effect Transistor via Solution Floating Method and Mechanical Property Evaluation

“…Moreover, the intensities of the (100) and (002) peaks drastically increased in the P3HT/EEG 10 nanocomposite film, which implies that the optimal content of EEG in the composite film can induce higher crystallinity and stronger intermolecular interactions. It has been reported that the P3HT molecules has more ability to crystallize in the composite film because the thiophene rings in a P3HT chain becomes interconnected with sp 2 -hybridized graphene surface [40,41].…”

Metal–organic framework nanosheets for enhanced performance of organic photovoltaic cells

“…[24][25][26][27][28][29] In the latter case, a wide range of additives have been investigated whose complimentary optical or electronic properties enable them to enhance the range of light absorbed, [30][31][32] facilitate more efficient electron or hole transport 33 or modify the morphology of the devices leading to improvements in performance and stability. [34][35][36] Two-dimensional materials are ideal candidates for use as additives thanks to their large surface areas and distinct electronic and optical properties. [37][38][39] Transition metal dichalcogenides (TMDCs) in particular have attracted signicant interest because of their thicknessdependant opto-electronic properties, 40 ambipolar charge transport, 41 chemical stability and direct band-gaps in the single layer form.…”