Related papers: Enhanced Organic Solar Cells Efficiency through Ad…
Organic photovoltaic (OPV) materials offer a promising avenue toward cost-effective solar energy utilization. However, optimizing donor-acceptor (D-A) combinations to achieve high power conversion efficiency (PCE) remains a significant…
Photo-induced charge transfer of positive and negative charges across the interface between an ordered organic semiconductor and a polymeric insulator is observed in the field-effect experiments. Immobilization of the transferred charge in…
In this thesis, two different optical management techniques for organics based solar cells are explored. The first part is focused on the development of a textured rear reflector for OPVs. The use of textured reflector (TR) facilitates an…
Most traditional semiconductor materials are based on the control of doping densities to create junctions and thereby functional and efficient electronic and optoelectronic devices. The technology development for halide perovskites had…
Perovskite solar cells (PSCs) without a hole transport layer (HTL) offer a cost-effective and stable alternative to conventional architectures, utilizing only an absorber layer and an electron transport layer (ETL). This study presents a…
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…
Asymmetrical horizontal interdot coupling was demonstrated to exist in a system of a single plane of self-assembled CdTe/ZnTe quantum dots. Photoluminescence excitation (PLE), second order photon correlation and optical orientation were…
We have demonstrated a high-performance low temperature solution processed electron selective contact consisting of 10 at% antimony doped tin oxide (ATO) and the neutral polymer polyethylenimine (PEI). Inverted organic photovoltaics (OPVs)…
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…
We report the site-specific probing of charge-transfer dynamics in a prototype system for organic photovoltaics (OPV) by picosecond time-resolved X-ray photoelectron spectroscopy. A layered system consisting of approximately two monolayers…
Suppressing charge recombination is key for organic solar cells to become commercial reality. However, there is still no conclusive picture of how recombination losses are influenced by the complex nanoscale morphology. Here, new insight is…
Organic light-emitting diodes (OLEDs) must be engineered to circumvent the efficiency limit imposed by the 3:1 ratio of triplet to singlet exciton formation following electron-hole capture. Here we show the spin nature of luminescent…
The oxygen evolution reaction (OER) at the surface of semiconductor photoanodes involves photo-generated holes that oxidize water. A certain fraction of the holes that reach the surface recombine with electrons from the conduction band,…
Regio-regular poly(3-hexylthiophene-2,5-diyl) (rr-P3HT), the work-horse of organic photovoltaics, has been recently exploited in bulk heterojunction (BHJ) configuration with phenyl-C61-butyric acid methyl ester (PCBM) for solution-processed…
Perovskite solar cells are one of the most attracting cells because of remarkably improved power conversion efficiency (PCE) recently. Toward their practical application, it is important not only to increase the PCE but also to elucidate…
Transient photovoltage (TPV) and voltage dependent charge extraction (CE) measurements were applied to poly(3-hexylthiophene)(P3HT):[6,6]-phenyl-C61 butyric acid methyl ester (PCBM) bulk heterojunction solar cells to analyze the limitations…
Perovskite solar cells (PSCs) are the fastest-growing photovoltaic (PV) technology in the solar cell community and have reached an efficiency close to that of commercial silicon (Si) solar cells. The organic-inorganic halide perovskite…
Photon impingement is capable of liberating electrons in semiconductors. When the electron transport is primarily governed by temperature gradients, high irreversibilities will result, thus lowering converters' efficiencies. A fundamental…
We demonstrate an ionically gated planar PS-PV solar cell with ultra-thick fullerene ETL with a porous CNT electron collector on top of it. Perovskite photovoltaic devices usually have undoped electron transport layers, usually thin like…
Photomultiplication-type organic photodetectors (PM-OPDs) promise exceptional sensitivity for weak-light detection but typically suffer from a gain-bandwidth trade-off where high external quantum efficiency (EQE) incurs large dark current…