Related papers: Exciton delocalization incorporated drift-diffusio…
Among the parameters determining the efficiency of an organic solar cell, the open-circuit voltage ($V_\text{OC}$) is the one with most room for improvement. Existing models for the description of $V_\text{OC}$ assume that photogenerated…
We demonstrate that efficient and nearly field-independent charge separation in organic planar heterojunction solar cells can be described by an incoherent hopping mechanism. We model the separation efficiency of electron-hole pairs created…
While silicon solar cells dominate global photovoltaic energy production, their continued improvement is hindered by the single junction limit. One potential solution is to use molecular singlet exciton fission to generate two electrons…
Large exciton diffusion lengths generally improve the performance of organic semiconductor devices, since they enable energy to be transported farther during the exciton lifetime. However, the physics of exciton motion in disordered organic…
Organic Photovoltaic devices (OPVs) are becoming adequately cost and energy efficient to be considered a good investment and it is, therefore, especially important to have a concrete understanding of their operation. We compute energies of…
We investigate the viability of highly efficient organic solar cells (OSCs) based on non-fullerene acceptors (NFA) by taking into consideration efficiency loss channels and stability issues caused by triplet excitons (TE) formation. OSCs…
Drift-diffusion model is an indispensable modeling tool to understand the carrier dynamics (transport, recombination, and collection) and simulate practical-efficiency of solar cells (SCs) through taking into account various carrier…
Non-fullerene acceptors (NFA), such as Y6, have significantly improved the efficiency of organic photovoltaic devices (OPVs). However, the fundamental processes behind the high efficiencies of NFA devices have remained incompletely…
We develop a quantum model for the dynamics of carrier injection in a band that presents a strong carrier-vibration coupling. This coupling modifies the spectral density of the band and can even create pseudo-gaps that sign the onset of…
This work presents a novel theoretical description of the non-equilibrium thermodynamics of charge separation process in organic solar cells (OSCs). Using the theory of stochastic thermodynamics, we connect the phonon-assisted dynamics and…
A typical signature of charge extraction in disordered organic systems is dispersive transport, which implies a distribution of charge carrier mobilities that negatively impact on device performance. Dispersive transport has been commonly…
The rise of organic electronics calls for versatile modeling tools. In this context, we develop a semiclassical Boltzmann theory that describes transport and excitonic processes in crystalline organic semiconductors on equal footing. The…
In this article we address the theoretical study of a multiscale drift-diffusion (DD) model for the description of photoconversion mechanisms in organic solar cells. The multiscale nature of the formulation is based on the co-presence of…
We present a detailed investigation of ultrafast (subpicosecond) exciton dynamics in the lattice model of a donor/acceptor heterojunction. Exciton generation by means of a photoexcitation, exciton dissociation, and further charge separation…
In photovoltaics (PVs) and artificial photosynthetic systems based on excitons, the question of how energy must be lost in overcoming the Coulomb barrier, converting excitons to free charges, is fundamental, as it determines the achievable…
We present and discuss a mathematical model for the operation of bilayer organic photovoltaic devices. Our model couples drift-diffusion-recombination equations for the charge carriers (specifically, electrons and holes) with a…
A one-dimensional many-body model is established to mimic the charge distribution and dynamics in nonfullerene organic solar cells. Two essential issues are taken into account in the model: The alternating donor and acceptor structure and…
Hot-carrier solar cells use the photon excess energy, that is, the energy exceeding the absorber bandgap, to do additional work. These devices have the potential to beat the upper limit for the photovoltaic power conversion efficiency set…
Kinetic Monte Carlo (KMC) simulations have been previously used to model and understand a wide range of behaviors in bulk heterojunction (BHJ) organic photovoltaic devices, from fundamental mechanisms to full device performance. One…
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…