A global crew of researchers used large-area perovskite movies handled with liquid crystals components to make photovoltaic modules with a licensed stabilized effectivity of 21.1% at an aperture space of 31 cm2.
A global analysis group sought to handle one of many commercialization challenges of perovskite photo voltaic cells, sustaining excessive effectivity when scaling up from the cell-to-module stage.
“Transitioning from laboratory-scale cells to bigger modules poses a notable effectivity loss,” the analysis’s lead writer, Yi Yang, instructed pv journal. “The best licensed stabilized aperture-area effectivity for perovskite photo voltaic modules exceeding 30 cm2 in space has not too long ago been noticed to plateau at roughly 19.5%. This is available in half from defects that come up throughout answer processing.”
Components utilized in prior analysis tended to mixture throughout the perovskite movie throughout co-precipitation in the midst of solvent evaporation, in response to Yang. “This led us to formulate a speculation: exploring various processing strategies past the generally used evaporative precipitation and crystallization might doubtlessly lower defects and the presence of insulating inclusions,” stated Yang.
The lecturers utilized thermotropic liquid crystals to keep away from the evaporative precipitation of standard components and the standard interface accumulation to allow uniform passivation of the large-area perovskite movies. “The strategy achieved a quick scan effectivity of 21.8% and stabilized effectivity of 21.1% for 30 cm2 perovskite mini modules with enhanced stability,” stated Yang.
Particularly, the crew labored with thermotropic liquid crystals, comparable to 3,4,5-trifluoro-4′-(trans-4-propylcyclohexyl)biphenyl (TFPCBP), embedding the fabric into the large-area perovskite movies.
The cells had been fabricated in an n–i–p configuration, using a fluorine-doped tin oxide (FTO) substrate, an electron transport layer (ETL) primarily based on a buckminsterfullerene (C60) and tin(IV) oxide (SnO2), a perovskite absorber, a Spiro-OMeTAD hole-transporting layer, and a gold (Au) metallic contact.
The perovskite photo voltaic modules consisted of six and 9 sub-cells related in sequence on 5 cm × 5 cm and 6.5 cm × 7 cm substrates, respectively.
The crew chosen thermotropic liquid crystals due to their “attribute mesomorphic part transition from a stable to an isotropic liquid part when heated.” They continue to be within the liquid part whereas the perovskite solidifies. “The environment friendly diffusion inside a combined liquid-solid system enabled TFPCBP molecules to distribute uniformly all through the movie for a homogenous passivation of defects,” stated Yang.
The lecturers performed a number of standards-based stability assessments of the handled cells and modules, together with reverse bias assessments, and located superior stability outcomes. For instance, the damp-heat stability of encapsulated modules was examined utilizing the ISOS-D-3 process, subjecting them to 85% RH at 85 C. “The TFPCBP-based modules retained 86% of their preliminary effectivity after 1,200 h, in contrast with 51% retention for the management,” famous the researchers, including that it “represents the longest-lived damp-heat stability in literature amongst n–i–p perovskite photo voltaic modules.”
The crew sees the potential to switch the expertise to slot-die coating processes to manufacture larger-area perovskite sub-modules. As well as, Yang sees alternatives for additional exploration of the performance and part construction of liquid crystal molecules to enhance passivation results and gadget stability.
Their findings can be found within the research “A thermotropic liquid crystal permits environment friendly and steady perovskite photo voltaic modules,” revealed in Nature Vitality. The scientists got here from Northwestern College, the Swiss Federal Institute of Know-how Lausanne, North China Electrical Energy College, the College of Toronto, and the US Division of Vitality’s Argonne Nationwide Laboratory.
This content material is protected by copyright and might not be reused. If you wish to cooperate with us and want to reuse a few of our content material, please contact: editors@pv-magazine.com.
