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.

Multi-site anchoring of single-molecule for efficient and stable perovskite solar cells with lead shielding

The emergence of perovskite solar cells(PSCs) has greatly promoted the progress of photovoltaic technologies.The rapid development of PSCs has been driven by the advances in optimizing perovskite films and their adjacent interfaces.However,the polycrystalline perovskite layers in most highly efficient PSCs still contain various defects that greatly limit photovoltaic performance and stability of the devices.Herein,we introduce a multifunctional additive ethylene diamine tetra methylene phosphonic sodium(EDTMPS) with multiple anchor points into the precursor of perovskite to improve the efficiency and stability of PSCs and provide in-situ protection of lead leakage.The addition of EDTMPS acts as a crystal growth controller and passivation agent for perovskite films,thereby slowing down the crystallization rate of the film and obtaining high-quality perovskite films.Our study also provides an insight into how the modifier modulate the interfacial energy level arrangement as well as affect transfer of charge carriers and their recombination under photoinduced excitation.As a result,the power conversion efficiency(PCE) of single subcell with a working area of 0.255 cm^(2) increases significantly from 20.03% to 23.37%.Moreover,we obtained a PCE of 19.16% for the 25 cm^(2) module.Importantly,the unencapsulated EDTMP-modified PSCs exhibit better operational and thermal stability,as well as in-situ absorption of leaked lead ions.

Multifunctional MOF@COF Nanoparticles Mediated Perovskite Films Management Toward Sustainable Perovskite Solar Cells

Although covalent organic frameworks(COFs)with highπ-conjugation have recently exhibited great prospects in perovskite solar cells(PSCs),their further application in PSCs is still hindered by face-to-face stacking and aggregation issues.Herein,metal-organic framework(MOF-808)is selected as an ideal platform for the in situ homogeneous growth of a COF to construct a core-shell MOF@COF nanoparticle,which could effectively inhibit COF stacking and aggregation.The synergistic intrinsic mechanisms induced by the MOF@COF nanoparticles for reinforcing intrinsic stability and mitigating lead leakage in PSCs have been explored.The complementary utilization ofπ-conjugated skeletons and nanopores could optimize the crystallization of large-grained perovskite films and eliminate defects.The resulting PSCs achieve an impressive power conversion efficiency of 23.61%with superior open circuit voltage(1.20 V)and maintained approximately 90%of the original power conversion efficiency after 2000 h(30-50%RH and 25-30℃).Benefiting from the synergistic effects of the in situ chemical fixation and adsorption abilities of the MOF@COF nanoparticles,the amount of lead leakage from unpackaged PSCs soaked in water(<5 ppm)satisfies the laboratory assessment required for the Resource Conservation and Recovery Act Regulation.

Vacancy healing for stable perovskite solar cells via bifunctional potassium tartrate

Perovskite solar cell has gained widespread attention as a promising technology for renewable energy.However, their commercial viability has been hampered by their long-term stability and potential Pb leakage. Herein, we demonstrate a bifunctional passivator of the potassium tartrate(PT) to address both challenges. PT minimizes the Pb leakage in perovskites and also heals cationic vacancy defects, resulting in improved device performance and stability. Benefiting from PT modification, the power conversion efficiency(PCE) is improved to 23.26% and the Pb leakage in unencapsulated films is significantly reduced to 9.79 ppm. Furthermore, the corresponding device exhibits no significant decay in PCE after tracking at the maximum power point(MPP) for 2000 h under illumination(LED source, 100 mW cm^(-2)).