Universal Encapsulation Adhesive for Lead Sedimentation and Attachable Perovskite Solar Cells with Enhanced Performance

In this work,a modified polyurethane adhesive(PUA)was prepared to realize a convenient encapsulation strategy for lead sedimentation and attachable perovskite solar cells(A-PSCs).The modified PUA can completely self-heal within 45 min at room temperature with an efficient lead ion-blocking rate of 99.3%.The PUA film can be coated on a metal electrode with slight efficiency improvement from 23.96%to 24.15%.The thermal stability at 65℃and the humidity stability at 55%relative humidity(RH)are superior to the devices encapsulated with polyisobutylene.The PUA film has strong adhesion to the flexible substrate and the initial efficiency of the flexible perovskite module(17.2%)encapsulated by PUA remains 92.6%within 1825 h.These results suggest that PUA encapsulation is universal for rigid and flexible PSCs with enhanced stability and low lead hazards.Moreover,it was found that flexible PSCs can be well attached to various substrates with PUA,providing a facile route for the A-PSCs in various scenarios without additional encapsulation and installation.

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)electrodes with enhanced conductivity and transparency for semitransparent perovskite solar cells

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)is an important organic electrode for solution-processed low-cost electronic devices.However,it requires doping and post-solvent treatment to improve its conductivity,and the chemicals used for such treatments may affect the device fabrication process.In this study,we developed a novel route for exploiting ultrafast lasers(femtosecond and picosecond laser)to simultaneously enhance the conductivity and transparency of PEDOT:PSS films and fabricate patterned solution-processed electrodes for electronic devices.The conductivity of the PEDOT:PSS film was improved by three orders of magnitude(from 3.1 to 1024 S·cm^(–1)),and high transparency of up to 88.5%(average visible transmittance,AVT)was achieved.Raman and depthprofiling X-ray photoelectron spectroscopy revealed that the oxidation level of PEDOT was enhanced,thereby increasing the carrier concentration.The surface PSS content also decreased,which is beneficial to the carrier mobility,resulting in significantly enhanced electrical conductivity.Further,we fabricated semitransparent perovskite solar cells using the as-made PEDOT:PSS as the transparent top electrodes,and a power conversion efficiency of 7.39%was achieved with 22.63%AVT.Thus,the proposed route for synthesizing conductive and transparent electrodes is promising for vacuum and doping-free electronics.