5 research outputs found
Pinhole Patching by Free Radicals for Highly Efficient Perovskite Solar Cells Fabricated in High-Moisture Environments
2-Hydroxy-2-methylpropiophenone (HMPP) and pentaerythritol
triacrylate
(PETA) are introduced into the perovskite layer via an antisolvent
to enhance the photovoltaic performance of perovskite solar cells
(PSCs) fabricated in a moisture atmosphere. Interestingly, the free
radicals created from the decomposition of HMPP and PETA by irradiating
UV light can effectively patch pinholes in the perovskite layer and
regrow the crystal to enlarge the grain size. PETA can interact with
Pb atoms via its lone pairs of electrons and forms a framework over
the perovskite layer by in situ UV polymerization, resulting in a
low trap-state density, high charge recombination resistance, long
charge lifetime, and reduced hysteresis. Additionally, the PETA framework
induces an enhanced driving force for charge separation at the heterojunction
of the electron transport layer and the perovskite layer by adjusting
the energy level of the perovskite. Consequently, a PSC with a silver
top electrode can be fabricated under 70% RH conditions, exhibiting
a high efficiency of 19.52% and good long-term stability. This enhancement
surpassed most reported values in the literature for PSCs fabricated
in a highly moist atmosphere
Fabrication of a Water-Stripped Free-Standing Silver Nanowire Network as the Top Electrode for Perovskite Solar Cells
Recently, there has been significant interest in inorganicāorganic
hybrid perovskite solar cells (PSCs) due to their excellent photovoltaic
performance. However, the fabrication of PSCsā top metallic
electrodes using thermal evaporation in a vacuum atmosphere significantly
increases the manufacturing cost and restricts large-scale production.
In this study, we propose a water separation method for the fabrication
of free-standing films of silver nanowires (AgNWs) that can be easily
stripped by using water and laminated onto perovskite devices as top
electrodes in an ambient atmosphere. The electrodes composed of long
AgNWs exhibit superior electrical properties compared to those composed
of shorter ones. We have identified that the reduced performance of
PSCs with AgNW electrodes is mainly attributed to the high oxide content
on the surface of AgNWs and the insufficient contact between the AgNW
networks and hole transport layers. To resolve these issues, we employed
sodium borohydride reduction and polyethoxysiloxane incorporation
techniques. Through these treatments, PSCs with AgNW electrodes achieved
a power conversion efficiency of 15.64%. This performance surpasses
that reported in the literature for PSCs with AgNW electrodes, demonstrating
the effectiveness of our approach
Fabrication of a Water-Stripped Free-Standing Silver Nanowire Network as the Top Electrode for Perovskite Solar Cells
Recently, there has been significant interest in inorganicāorganic
hybrid perovskite solar cells (PSCs) due to their excellent photovoltaic
performance. However, the fabrication of PSCsā top metallic
electrodes using thermal evaporation in a vacuum atmosphere significantly
increases the manufacturing cost and restricts large-scale production.
In this study, we propose a water separation method for the fabrication
of free-standing films of silver nanowires (AgNWs) that can be easily
stripped by using water and laminated onto perovskite devices as top
electrodes in an ambient atmosphere. The electrodes composed of long
AgNWs exhibit superior electrical properties compared to those composed
of shorter ones. We have identified that the reduced performance of
PSCs with AgNW electrodes is mainly attributed to the high oxide content
on the surface of AgNWs and the insufficient contact between the AgNW
networks and hole transport layers. To resolve these issues, we employed
sodium borohydride reduction and polyethoxysiloxane incorporation
techniques. Through these treatments, PSCs with AgNW electrodes achieved
a power conversion efficiency of 15.64%. This performance surpasses
that reported in the literature for PSCs with AgNW electrodes, demonstrating
the effectiveness of our approach
Hydrophilic Ligand Exchange Induces Improved Upconversion Nanoparticle Incorporation in Dye-Sensitized Solar Cells with Efficiency Exceeding 8% in a Low-Temperature Fabrication Process
We synthesized coreāshell
upconversion nanoparticles (UCNPs)
with a composition of LiYF4:Yb0.2/Er0.02/Ho0.02/Tm0.02@LiYF4:Yb0.2 and incorporated them into the photoanodes of dye-sensitized solar
cells (DSSCs) fabricated through a low-temperature process. The as-prepared
hydrophobic UCNPs displayed a good protection ability to prevent the
ingress of electrolyte but caused cracking in the mesoporous layers.
To resolve this issue, we modified the as-prepared UCNPs by performing
ligand exchange using 4-aminobenzoic acid (4ABA), transforming the
hydrophobic surface into a hydrophilic one. By design of a three-layer
structure to prevent electrolyte ingress, the hydrophilic nature of
the 4ABA-modified UCNPs enabled better incorporation into the photoanodes.
Consequently, the incorporation of 4ABA-UCNPs significantly improved
the power conversion efficiency of DSSCs from 6.32 to 8.22%. This
enhancement surpassed most reported values in the literature for DSSCs
fabricated using a low-temperature process. Importantly, compared
to other hydrophilic ligands, the use of 4ABA did not noticeably increase
the charge transfer resistance due to its appropriate molecular weight
Synthesis of Dicarboxylic Acids Comprising an Ether Linkage and Cyclic Skeleton and Its Further Application for High-Performance Aluminum Electrolyte Capacitors
Aluminum electrolytic
capacitors are essential components in all
electronic devices, and it is known that their longevity depends on
the performance of their electrolytes. We synthesized dicarboxylic
acids having ether bonds showing the good solubility in ethylene glycol
as a solvent and simultaneously developed a complete halogen removal
method, which is strictly prohibited in capacitors. Moreover, the
incorporation of bulky Ī±-substituents and cyclic structures
dramatically improved their heat resistance and can withstand high
voltage, i.e., 764 V