相关论文: Singlet-triplet annihilation limits exciton yield …
Triplet excitons have been the focus of considerable attention with regards to the functioning of polymer solar cells, because these species are long-lived and quench subsequently generated singlet excitons in their vicinity. The role of…
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…
The number of excitons that conjugated polymers can support at any one time underpins their optoelectronic performance in light emitting diodes and as laser gain media, as it sets a natural limit on exciton density. Here we have measured…
Understanding of degradation mechanisms in polymer:fullerene bulk-heterojunctions on the microscopic level aimed at improving their intrinsic stability is crucial for the breakthrough of organic photovoltaics. These materials are vulnerable…
Photochemical upconversion is a promising way to boost the efficiency of solar cells using triplet exciton annihilation. Currently, predicting the performance of photochemical upconversion devices is challenging. We present an open source…
Blinking of the photoluminescence (PL) emitted from individual conjugated polymer chains is one of the central observations made by single-molecule spectroscopy (SMS). Important information, e.g., regarding excitation energy transfer, can…
We present a theoretical study of degradation mechanisms for photoinduced oxidation in organic polymers in the condensed phase, using poly(3-hexylthiophene)(P3HT) as an example. Applying density functional theory with a hybrid density…
Singlet exciton fission has the potential to increase the efficiency of crystalline silicon solar cells beyond the conventional single junction limit. Perhaps the largest obstacle to achieving this enhancement is uncertainty about energy…
We study the assembling of P3HT chains in vacuo by means of a combination of first principles density functional theory and model potential molecular dynamics. We find that, in the absence of any external constraints, the pi-pi interchain…
Organic bulk-heterojunctions (BHJ) and solar cells containing the trimetallic nitride endohedral fullerene 1-[3-(2-ethyl)hexoxy carbonyl]propyl-1-phenyl-Lu3N@C80 (Lu3N@C80-PCBEH) show an open circuit voltage (VOC) 0.3 V higher than similar…
Ultrathin polymer-graphene heterostructures are promising materials for next generation optoelectronic and photovoltaic technologies, while the influence of the polymer's structural variation on interfacial charge transfer remains unclear.…
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…
Singlet fission, an exciton multiplication process in organic semiconductors which converts one singlet exciton into two triplet excitons is a promising way to reduce thermalization losses in conventional solar cells. One way to harvest…
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…
The great progress in organic photovoltaics (OPV) over the past few years has been largely achieved by the development of non-fullerene acceptors (NFAs), with power conversion efficiencies now approaching 20%. To further improve device…
Inclusion of heavy metal atoms in a polymer backbone allows transitions between the singlet and triplet manifolds. Interfacial dissociation of triplet excitons constitutes a viable mechanism for enhancing photovoltaic (PV) efficiencies in…
The exciton dynamics in monolayer black phosphorus is investigated over a very wide range of photoexcited exciton densities using time resolved photoluminescence. At low excitation densities, the exciton dynamics is successfully described…
Motivated by an experiment in which the singlet-triplet gap in triphenylene based copolymers was effectively tuned, we used time dependent density functional theory (TDDFT) to reproduce the main results. By means of conventional and…
Singlet fission is a form of multiple exciton generation which occurs in organic chromophores when a high energy singlet exciton separates into two lower energy triplet excitons, each with approximately half the singlet energy. Since this…
A combination of ultrafast, long-range and low-loss excitation energy transfer from the photo-receptor location to a functionally active site is essential for cost-effective polymeric semiconductors. Delocalized electronic wavefunctions…