The recently developed planar architecture (ITO/ZnO/PbS-TBAI/PbS-EDT/Au) has greatly improved the power conversion efficiency of colloidal quantum dot photovoltaics (QDPVs). However, the performance is still far below the theoretical expectations and trap states in the PbS-TBAI film are believed to be the major origin, characterization and understanding of the traps are highly demanded to develop strategies for continued performance improvement. Here employing impedance spectroscopy we detect trap states in the planar PbS QDPVs. We determined a trap state of about 0.34 eV below the conduction band with a density of around 3.2 × 10 cm eV. Temperature dependent open-circuit voltage analysis, temperature dependent diode property analysis and temperature dependent build-in potential analysis consistently denotes an below-bandgap activation energy of about 1.17-1.20 eV.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5109221 | PMC |
http://dx.doi.org/10.1038/srep37106 | DOI Listing |
J Phys Chem A
December 2024
Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea.
A photodetachment and photoelectron spectroscopic study by employing a cryogenically cooled ion trap combined with a velocity-map imaging setup has been carried out to unravel the vibrational structures and autodetachment dynamics of the dipole-bound states (DBSs) of -, -, and -methylphenolate anions (-, -, and -CHPhO). The electron binding energy of the DBS increases monotonically with the increase of the neutral dipole moment to give respective values of 66 ± 15, 123 ± 18, or 154 ± 14 cm for the -, -, or -isomer. The different electron-donating effects of the methyl moieties in the three geometrically different isomers seem to be reflected in the experiment.
View Article and Find Full Text PDFLangmuir
December 2024
Key Laboratory of Photonic Materials and Devices Physics for Oceanic Applications, Ministry of Industry and Information Technology of China, College of Physics and Optoelectronic Engineering, Harbin Engineering University, Harbin 150001, China.
Due to intrinsic defects in blue-light-emitting perovskite materials, the charge carriers are prone to being trapped by the trap states. Therefore, the preparation of efficient blue-light-emitting perovskite materials remains a significant challenge. Herein, CsPb(Cl/Br) nanocrystal (NCs)@SiO structures were fabricated through hydrolyzing (3-aminopropyl)-triethoxysilane (APTS).
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding 071003, China.
Epoxy resin (EP) is an outstanding polymer material known for its low cost, ease of preparation, excellent electrical insulation properties, mechanical strength, and chemical stability. It is widely used in high- and ultra-high-voltage power transmission and transformation equipment. However, as voltage levels continue to increase, EP materials are gradually failing to meet the performance demands of operational environments.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
State Key Laboratory of ASIC and System, Shanghai Institute of Intelligent Electronics & Systems, School of Microelectronics, Fudan University, Shanghai 200433, China.
The trapping mechanism at the AlGaN/GaN interface in the p-GaN high electron mobility transistors (HEMTs) and its impact on the turn-on characteristics of direct-coupled FET logic (DCFL) inverters were investigated across various supply voltages () and test frequencies (). The frequency-conductance method identified two trap states at the AlGaN/GaN interface (trap activation energy - ranges from 0.345 eV to 0.
View Article and Find Full Text PDFCurr Issues Mol Biol
November 2024
Faculty of Pharmaceutical Sciences, Ubon Ratchathani University, Ubon Ratchathani 34190, Thailand.
Hepatocellular carcinoma (HCC) is the most common form of liver cancer in humans, with an increasing incidence worldwide. The current study aimed to explore the molecular mechanisms that inhibit the proliferation of HepG2 cells, a hepatoblastoma-derived cell line. MSC-derived exosomes (UC-MSCs) were prepared with a median particle size (N50) of 135.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!