@article{guo_chauhan_woodward_mcandrews_thapa_lefler_li_wang_darabi_mcgehee_et al._2023, title={<i>In situ</i> Stress Monitoring Reveals Tension and Wrinkling Evolutions during Halide Perovskite Film Formation}, volume={9}, ISSN={["2380-8195"]}, DOI={10.1021/acsenergylett.3c02079}, abstractNote={Metal halide perovskites (MHPs) are promising candidates for next-generation thin film photovoltaics and high-performance tandems. Solution-processed MHP films are susceptible to residual stress that can induce undesirable surface wrinkles. However, the origins and evolution of stress during solution processing remain elusive. In this work, we utilize multimodal in situ characterizations, including substrate curvature, reflectance, absorbance, and photoluminescence, to monitor stress and morphology evolution during MHP film formation. A film formation model emerges, consisting of a perovskite top crust on a semirigid sol with the ability to transfer mechanical forces. The phase transformation induces tension in the MHP crust, while shrinkage of the sol causes additional compression and surface wrinkles. Wrinkle-free films are formed through dynamically balancing forces between the crust and the sol. This study provides a powerful toolkit for the fast-growing area of stress engineering in MHP photovoltaics to achieve dynamic control of film stress and surface morphology.}, number={1}, journal={ACS ENERGY LETTERS}, author={Guo, Boyu and Chauhan, Mihirsinh and Woodward, Nathaniel R. and McAndrews, Gabriel R. and Thapa, Gaurab J. and Lefler, Benjamin M. and Li, Ruipeng and Wang, Tonghui and Darabi, Kasra and McGehee, Michael D. and et al.}, year={2023}, month={Dec}, pages={75–84} }
 @article{ghasemi_guo_darabi_wang_wang_huang_lefler_taussig_chauhan_baucom_et al._2023, title={A multiscale ion diffusion framework sheds light on the diffusion-stability-hysteresis nexus in metal halide perovskites}, ISSN={["1476-4660"]}, DOI={10.1038/s41563-023-01488-2}, abstractNote={Stability and current-voltage hysteresis stand as major obstacles to the commercialization of metal halide perovskites. Both phenomena have been associated with ion migration, with anecdotal evidence that stable devices yield low hysteresis. However, the underlying mechanisms of the complex stability-hysteresis link remain elusive. Here we present a multiscale diffusion framework that describes vacancy-mediated halide diffusion in polycrystalline metal halide perovskites, differentiating fast grain boundary diffusivity from volume diffusivity that is two to four orders of magnitude slower. Our results reveal an inverse relationship between the activation energies of grain boundary and volume diffusions, such that stable metal halide perovskites exhibiting smaller volume diffusivities are associated with larger grain boundary diffusivities and reduced hysteresis. The elucidation of multiscale halide diffusion in metal halide perovskites reveals complex inner couplings between ion migration in the volume of grains versus grain boundaries, which in turn can predict the stability and hysteresis of metal halide perovskites, providing a clearer path to addressing the outstanding challenges of the field.}, journal={NATURE MATERIALS}, author={Ghasemi, Masoud and Guo, Boyu and Darabi, Kasra and Wang, Tonghui and Wang, Kai and Huang, Chiung-Wei and Lefler, Benjamin M. and Taussig, Laine and Chauhan, Mihirsinh and Baucom, Garrett and et al.}, year={2023}, month={Feb} }
 @article{park_wei_xu_atapattu_eickemeyer_darabi_grater_yang_liu_teale_et al._2023, title={Engineering ligand reactivity enables high-temperature operation of stable perovskite solar cells}, volume={381}, ISSN={["1095-9203"]}, DOI={10.1126/science.adi4107}, abstractNote={
            Perovskite solar cells (PSCs) consisting of interfacial two- and three-dimensional heterostructures that incorporate ammonium ligand intercalation have enabled rapid progress toward the goal of uniting performance with stability. However, as the field continues to seek ever-higher durability, additional tools that avoid progressive ligand intercalation are needed to minimize degradation at high temperatures. We used ammonium ligands that are nonreactive with the bulk of perovskites and investigated a library that varies ligand molecular structure systematically. We found that fluorinated aniliniums offer interfacial passivation and simultaneously minimize reactivity with perovskites. Using this approach, we report a certified quasi–steady-state power-conversion efficiency of 24.09% for inverted-structure PSCs. In an encapsulated device operating at 85°C and 50% relative humidity, we document a 1560-hour
            T
            85
            at maximum power point under 1-sun illumination.
          }, number={6654}, journal={SCIENCE}, author={Park, So Min and Wei, Mingyang and Xu, Jian and Atapattu, Harindi R. and Eickemeyer, Felix T. and Darabi, Kasra and Grater, Luke and Yang, Yi and Liu, Cheng and Teale, Sam and et al.}, year={2023}, month={Jul}, pages={209–215} }
 @article{park_wei_lempesis_yu_hossain_agosta_carnevali_atapattu_serles_eickemeyer_et al._2023, title={Low-loss contacts on textured substrates for inverted perovskite solar cells}, ISSN={["1476-4687"]}, DOI={10.1038/s41586-023-06745-7}, journal={NATURE}, author={Park, So Min and Wei, Mingyang and Lempesis, Nikolaos and Yu, Wenjin and Hossain, Tareq and Agosta, Lorenzo and Carnevali, Virginia and Atapattu, Harindi R. and Serles, Peter and Eickemeyer, Felix T. and et al.}, year={2023}, month={Oct} }
 @article{wang_li_ardekani_serrano-lujan_wang_ramezani_wilmington_chauhan_epps_darabi_et al._2023, title={Sustainable materials acceleration platform reveals stable and efficient wide-bandgap metal halide perovskite alloys}, volume={6}, ISSN={["2590-2385"]}, DOI={10.1016/j.matt.2023.06.040}, abstractNote={The vast chemical space of emerging semiconductors, like metal halide perovskites, and their varied requirements for semiconductor applications have rendered trial-and-error environmentally unsustainable. In this work, we demonstrate RoboMapper, a materials acceleration platform (MAP), that achieves 10-fold research acceleration by formulating and palletizing semiconductors on a chip, thereby allowing high-throughput (HT) measurements to generate quantitative structure-property relationships (QSPRs) considerably more efficiently and sustainably. We leverage the RoboMapper to construct QSPR maps for the mixed ion FA1−yCsyPb(I1−xBrx)3 halide perovskite in terms of structure, bandgap, and photostability with respect to its composition. We identify wide-bandgap alloys suitable for perovskite-Si hybrid tandem solar cells exhibiting a pure cubic perovskite phase with favorable defect chemistry while achieving superior stability at the target bandgap of ∼1.7 eV. RoboMapper’s palletization strategy reduces environmental impacts of data generation in materials research by more than an order of magnitude, paving the way for sustainable data-driven materials research.}, number={9}, journal={MATTER}, author={Wang, Tonghui and Li, Ruipeng and Ardekani, Hossein and Serrano-Lujan, Lucia and Wang, Jiantao and Ramezani, Mahdi and Wilmington, Ryan and Chauhan, Mihirsinh and Epps, Robert W. and Darabi, Kasra and et al.}, year={2023}, month={Sep}, pages={2963–2986} }
 @article{zhang_darabi_nia_krishna_ahlawat_guo_almalki_su_ren_bolnykh_et al._2022, title={A universal co-solvent dilution strategy enables facile and cost-effective fabrication of perovskite photovoltaics}, volume={13}, ISSN={2041-1723}, url={http://dx.doi.org/10.1038/s41467-021-27740-4}, DOI={10.1038/s41467-021-27740-4}, abstractNote={Abstract}, number={1}, journal={Nature Communications}, publisher={Springer Science and Business Media LLC}, author={Zhang, Hong and Darabi, Kasra and Nia, Narges Yaghoobi and Krishna, Anurag and Ahlawat, Paramvir and Guo, Boyu and Almalki, Masaud Hassan S. and Su, Tzu-Sen and Ren, Dan and Bolnykh, Viacheslav and et al.}, year={2022}, month={Jan} }
 @article{dong_fu_seyitliyev_darabi_mendes_lei_chen_chang_amassian_gundogdu_et al._2022, title={Cavity Engineering of Perovskite Distributed Feedback Lasers}, volume={9}, ISSN={2330-4022 2330-4022}, url={http://dx.doi.org/10.1021/acsphotonics.2c00917}, DOI={10.1021/acsphotonics.2c00917}, number={9}, journal={ACS Photonics}, publisher={American Chemical Society (ACS)}, author={Dong, Qi and Fu, Xiangyu and Seyitliyev, Dovletgeldi and Darabi, Kasra and Mendes, Juliana and Lei, Lei and Chen, Yi-An and Chang, Chih-Hao and Amassian, Aram and Gundogdu, Kenan and et al.}, year={2022}, month={Aug}, pages={3124–3133} }