相关论文: Transport resistance strikes back: unveiling its i…
Organic photovoltaics are a promising solar cell technology well-suited to mass production using roll-to-roll processes. The efficiency of lab-scale solar cells has exceeded 20% and considerable attention is currently being given to…
The enhancement of the fill factor in the current generation of perovskite solar cells is the key for further efficiency improvement. Thus, methods to quantify the fill factor losses are urgently needed. A classical method to quantify Ohmic…
The effective conductivity determines the reciprocal of the transport resistance, the dominant loss of fill factor in organic solar cells. We experimentally determine the dependence of effective conductivity on its electron and hole…
Although the power conversion efficiencies of organic solar cells (OSCs) have surpassed 20%, they still lag behind commercial inorganic solar cells and emerging perovskite solar cells. To bridge this efficiency gap, improving the fill…
A modified detailed balance model is built to understand and quantify efficiency loss of perovskite solar cells. The modified model captures the light-absorption dependent short-circuit current, contact and transport-layer modified carrier…
The charge carrier mobility is a key parameter for the organic bulk heterojunction solar cell efficiency. It was recently shown that the interplay charge carrier transport and recombination, both depending on electron and hole mobilities,…
Surface recombination has a major impact on the open-circuit voltage ($V_\text{oc}$) of organic photovoltaics. Here, we study how this loss mechanism is influenced by imbalanced charge transport in the photoactive layer. As a model system,…
Stability is one of the most important challenges facing organic solar cells (OSC) on their path to commercialization. In the high-performance material system PM6:Y6 studied here, investigate degradation mechanisms of inverted photovoltaic…
Understanding and quantifying the main loss factors affecting the power conversion efficiency of perovskite solar cells are urgently needed. In this work, based on semiconductor physics, the expressions of bulk and surface recombination…
Perovskite-silicon tandem technology has exceeded the single junction theoretical efficiency limit. However, there is still distance to the thermodynamic limit mainly caused by the fill factor. This work presents a methodology to illustrate…
Recombination losses contribute to reduce $J_{SC}$, $V_{OC}$ and the fill factor of organic solar cells. Recent advances in non-fullerene organic photovoltaics have shown, nonetheless, that efficient charge generation can occur under small…
State of the art organic solar cells exhibit power conversion efficiencies of 18 % and above. These devices benefit from the suppression of free charge recombination with regard to the Langevin-limit of charge encounter in a homogeneous…
Apparent recombination orders exceeding the value of two expected for bimolecular recombination have been reported for organic solar cells in various publications. Two prominent explanations are bimolecular losses with a carrier…
In a recent paper, Street et al. [Phys. Rev. B 81, 205307 (2010)] propose first order recombination due to interface states to be the dominant loss mechanism in organic bulk heterojunction solar cells, based on steady-state current--voltage…
The power conversion efficiency of organic solar cells based on donor--acceptor blends is governed by an interplay of polaron pair dissociation and bimolecular polaron recombination. Both processes are strongly dependent on the charge…
Space charge effects can significantly degrade charge collection in organic photovoltaics (OPVs), especially in thick-film devices. The two main causes of space charge are doping and imbalanced transport. Although these are completely…
The charge carrier dynamics of organic solar cells are strongly influenced by trapping and allow to draw conclusions on the loss mechanisms limiting the photovoltaic performance. In this study we derive the recombination order \Delta\ of…
Metastable defects can decisively influence the diode factor and thus the efficiency of a solar cell. The diode factor is also influenced by the doping level and the recombination mechanisms in the solar cell. Here we quantify how the…
A recently suggested reciprocity relation states that the current transport efficiency from the junction to the cell terminal can be determined by differentiating luminescence images with respect to the terminal voltage. The validity of…
Electrical transients enabled by optical excitation and electric detection provide a distinctive opportunity to study the charge transport, recombination and even the hysteresis of a solar cell in a much wider time window ranging from…