2 research outputs found
Surface-Plasmonic-Coupled Photodetector Based on MAPbI<sub>3</sub> Perovskites with Au Nanoparticles: Significantly Enhanced Photoluminescence and Photodetectivity
Organic–inorganic metal halide perovskites (OMHPs)
are promising
active materials suitable for highly efficient solar cells, photodetectors,
light-emitting diodes, and sensors. In this study, methylammonium
lead iodide (MAPbI3) thin sheets (TSs) were synthesized
as OMHPs using both hybrid vapor-solution method for optical study
and anti-solvent solution method for the photodetector. π-Conjugated
polyelectrolyte (π-CPE), such as poly(9,9-bis(4′-sulfonatobutyl)fluorene-alt-1,4-phenylene)
potassium (FPS-K), was spin-coated on the MAPbI3 TS, and
functionalized gold nanoparticles (Au-NPs) were hybridized. The laser
confocal microscope photoluminescence (PL) intensity of the MAPbI3 TS was significantly enhanced after hybridization with Au-NPs/FPS-K,
owing to the passivating effect of the FPS-K and the generation of
extra-photoexcited charges by local surface plasmon resonance (LSPR)
coupling with Au-NPs. These results were supported by the variation
in the exciton lifetime measured from the time-resolved PL decay curves.
The photocurrent of the MAPbI3 photodetector increased
up to 1.1 × 104 times, and the photoresponsivity (R) and photodetectivity (D*) increased
by 70 and 13 times, respectively, with the hybridization of Au-NPs/FPS-K.
The highest D* of the Au-NPs/FPS-K/MAPbI3 photodetector was measured to be 7.5 × 1010 Jones
at 735 nm excitation. The power and wavelength dependencies of R and D* for the MAPbI3 photodetector
were also significantly improved by the Au-NPs/FPS-K hybrid. These
results support the development of high-performance perovskite photodetectors
utilizing LSPR coupling with the π-CPE layer
Enhanced Efficiency and Stability of Novel Pseudo-ternary Polymer Solar Cells Enabled by a Conjugated Donor Block Copolymer
The recent breakthrough in power conversion efficiencies
(PCEs)
of polymer solar cells (PSCs) that contain an active layer of a ternary
system has achieved values of 18–19%; this has sparked interest
for further research. However, this system has difficulties in optimizing
the composition and controlling the interaction between the three
active materials. In this study, we investigated the use of a donor1 (D1)–donor2 (D2)
conjugated block copolymer (CBP), PM6-b-TT, to replace
the physical blend of two donors. PM6-b-TT, which
exhibits an extended absorption range, was synthesized by covalently
bonding PM6, a medium-band gap polymer, with PBDT-TT, a wide-band
gap polymer. The blend films containing PM6-b-TT
and Y6-BO acceptor, demonstrated excellent crystallinity and a film
morphology favorable for PSCs. The corresponding pseudo-ternary PSC
exhibited significantly higher PCE and thermal stability than the
PM6:PBDT-TT-based ternary device. This study unambiguously demonstrates
that the novel D1–D2 CBP strategy, combined
with the conventional binary and ternary system advantages, is a promising
material production strategy that can boost the performance of future
PSCs