Related papers: Homocoupling defects in a conjugated polymer limit…
We develop a general theory of electron--hole recombination in organic light emitting diodes that leads to formation of emissive singlet excitons and nonemissive triplet excitons. We briefly review other existing theories and show how our…
Silicon heterojunction (SHJ) solar cells represent a promising technological approach towards higher photovoltaics efficiencies and lower fabrication cost. While the device physics of SHJ solar cells have been studied extensively in the…
There is an enormous potential in applying conjugated polymers in novel organic opto-electronic devices such as light emitting diodes and solar cells. Although prototypes and first products exist, a comprehensive understanding of the…
In organic bulk heterojunction solar cells, the open circuit voltage ($V_\mathrm{oc}$) suffers from an ultra-high loss at low temperatures. In this work we investigate the origin of the loss through calculating the $V_\mathrm{oc}-T$ plots…
Measurements of the diffusion length L for triplet excitons in small molecular-weight organic semiconductors are commonly carried out using a technique in which a phosphorescent-doped probe layer is set in the vicinity of a supposed exciton…
After the efficiency of organic photovoltaic (OPV) cells achieved more than 10%, the control of stability and degradation mechanisms of solar cells became a prominent task. The improvement of device efficiency due to incorporation of a…
The power conversion efficiency of organic solar cells has recently improved beyond 20%. The active layers of these devices comprise of at least two organic semiconductors, forming a type II heterojunction. Hereby, the device performance is…
Electric coupling between subcells of a monolithically grown multijunction solar cell in short circuit allows their simultaneous and independent characterization by means of photo- and electroreflectance. The photovoltage generated by…
In this article, we investigate the effect of prolonged light exposure on silicon heterojunction solar cells. We show that, although light exposure systematicallyimproves solar cell efficiency in the case of devices using intrinsic and…
Models of organic bulk heterojunction photovoltaics which include the effect of spatially varying composition of donor/acceptor materials are developed and analyzed. Analytic expressions for the current-voltage relation in simplified cases…
We investigated photogeneration yield and recombination dynamics in blends of poly(3-hexyl thiophene) (P3HT) and poly[2-methoxy-5-(30,70-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) with [6,6]- phenyl-C61 butyric acid methyl ester…
The influence of hydroxyectoine on the properties of the aqueous solution in presence of DPPC lipid bilayers is studied via semi-isotropic constant pressure (NPT) Molecular Dynamics simulations. We investigate the solvent-co-solute behavior…
Engineering the energetics of perovskite photovoltaic devices through the deliberate introduction of dipoles to control the built-in potential of the devices offers the opportunity to enhance their performance without the need to modify the…
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…
We report on terrylene-3,4:11,12-bis(dicarboximide) (TDI) as electron acceptor for bulk-heterojunction solar cells using poly(3-hexyl thiophene) (P3HT) as complementary donor component. Enhanced absorption was observed in the blend compared…
In conventional solar cell semiconductor materials (predominantly Si) photons with energy higher than the band gap initially generate hot electrons and holes, which subsequently cool down to the band edge by phonon emission. Due to the…
In parallel-connected cells, cell-to-cell (CtC) heterogeneities can lead to current and thermal gradients that may adversely impact the battery performance and aging. Sources of CtC heterogeneity include manufacturing process tolerances,…
Hy brid composites obtained upon blending conjugated polymers and colloidal inorganic semiconductor nanocrystals are regarded as attractive photo-active materials for optoelectronic applications. Here we demonstrate that tailoring…
Since the seminal work on MoS2 monolayers, photoexcitation in atomically-thin transition metal dichalcogenides (TMDCs) has been assumed to result in excitons with large binding energies (~ 200-600 meV). Because the exciton binding energies…
In the strong light-matter coupling regime realized e.g. by integrating semiconductors into optical microcavities, polaritons as new hybrid light-matter quasi-particles are formed. The corresponding change in the dispersion relation has a…