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All-solid-state batteries (ASSBs) have garnered considerable attention as promising candidates for next-generation energy storage systems due to their potentially simultaneously enhanced safety capacities and improved energy densities. However, the solid future still calls for materials with high ionic conductivity, electrochemical stability, and favorable interfacial compatibility. In this study, we present a series of halide solid-state electrolytes (SSEs) utilizing a doping strategy with highly valent elements, demonstrating an outstanding combination of enhanced ionic conductivity and oxidation stability. Among these, Li2.6In0.8Ta0.2Cl6 emerges as the standout performer, displaying a superionic conductivity of up to 4.47 mS cm-1 at 30 °C, along with a low activation energy barrier of 0.321 eV for Li+ migration. Additionally, it showcases an extensive oxidation onset of up to 5.13 V (vs Li+/Li), enabling high-voltage ASSBs with promising cycling performance. Particularly noteworthy are the ASSBs employing LiCoO2 cathode materials, which exhibit an extended cyclability of over 1400 cycles, with 70% capacity retention under 4.6 V (vs Li+/Li), and a capacity of up to 135 mA h g-1 at a 4 C rate, with the loading of active materials at 7.52 mg cm-2. This study demonstrates a feasible approach to designing desirable SSEs for energy-dense, highly stable ASSBs.
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Introducing molecular chirality into perovskite crystal structures has enabled the control of carrier spin states, giving rise to circularly polarized luminescence (CPL) in thin films and circularly polarized electroluminescence (CPEL) in LEDs. Spin-LEDs can be fabricated either through a spin-filtering layer enabled by chiral-induced spin selectivity or a chiral emissive layer. The former requires a high degree of spin polarization and a compatible spinterface for efficient spin injection, which might not be easily integrated into LEDs. Alternatively, a chiral emissive layer can also generate circularly polarized electroluminescence, but the efficiency remains low and the fundamental mechanism is elusive. In this work, we report an efficient green LED based on quasi-two-dimensional (quasi-2D) chiral perovskites as the emitting layer (EML), where CPEL is directly produced without separate carrier spin injection. The optimized chiral perovskite thin films exhibited strong CPL at 535 nm with a photoluminescence quantum yield (PLQY) of 91% and a photoluminescence dissymmetry factor (glum) of 8.6 × 10-2. Efficient green spin-LEDs were successfully demonstrated, with a large EL dissymmetry factor (gEL) of 7.8 × 10-2 and a maximum external quantum efficiency (EQE) of 13.5% at room temperature. Ultrafast transient absorption (TA) spectroscopic study shows that the CPEL is generated from a rapid energy transfer accompanied by spin transfer from 2D to 3D perovskites. Our study not only demonstrates a reliable approach to achieve high performance spin-LEDs but also reveals the fundamental mechanism of CPEL with an emissive layer of chiral perovskites.
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The control of spin relaxation mechanisms is of great importance for spintronics applications as well as for fundamental studies. Layered metal-halide perovskites represent an emerging class of semiconductors with rich optical spin physics, showing potential for spintronic applications. However, a major hurdle arises in layered metal-halide perovskites with strong spin-orbit coupling, where the spin lifetime becomes extremely short due to D'yakonov-Perel' scattering and Bir-Aronov-Pikus at high carrier density. Using the circularly polarized pump-probe transient reflection technique, we experimentally reveal the important scattering for spin relaxation beyond the electron-hole exchange strength in the Dion-Jacobson (DJ)-type 2D perovskites (3AMP)(MA)n-1PbnI3n+1 [3AMP = 3-(aminomethyl)piperidinium, n = 1-4]. Despite a more than 10-fold increase in carrier concentration, the spin lifetimes for n = 3 and 4 are effectively maintained. We reveal neutral impurity and polar optical phonon scatterings as significant contributors to the momentum relaxation rate. Furthermore, we show that more octahedral distortions induce a larger deformation potential which is reflected on the acoustic phonon properties. Coherent acoustic phonon analysis indicates that the polaronic effect is crucial in achieving control over the scattering mechanism and ensuring spin lifetime protection, highlighting the potential of DJ-phase perovskites for spintronic applications.
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Hot carrier solar cells could offer a solution to achieve high efficiency solar cells. Due to the hot-phonon bottleneck in perovskites, the hot carrier lifetime could reach hundreds of ps. Such that exploring perovskites could be a good way to promote hot carrier technology. With the incorporation of large organic cations, the hot carrier lifetime can be improved. By using ultrafast transient spectroscopy, the hot carrier relaxation and extraction kinetics are measured. From the transient kinetics, 2-phenyl-acetamidine cation based perovskites exhibit the highest initial carrier temperature, longest carrier relaxation, and slowest hot carrier relaxation. Such superior behavior could be attributed to reduced electron-phonon coupling induced by lattice strain, which is a result of the large organic cation and also a possible surface electronic state change. Our discovery exhibits the potential to use large organic cations for the use of hot carrier perovskite solar cells.
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Perovskite photovoltaics, typically based on a solution-processed perovskite layer with a film thickness of a few hundred nanometres, have emerged as a leading thin-film photovoltaic technology. Nevertheless, many critical issues pose challenges to its commercialization progress, including industrial compatibility, stability, scalability and reliability. A thicker perovskite film on a scale of micrometres could mitigate these issues. However, the efficiencies of thick-film perovskite cells lag behind those with nanometre film thickness. With the mechanism remaining elusive, the community has long been under the impression that the limiting factor lies in the short carrier lifetime as a result of defects. Here, by constructing a perovskite system with extraordinarily long carrier lifetime, we rule out the restrictions of carrier lifetime on the device performance. Through this, we unveil the critical role of the ignored lattice strain in thick films. Our results provide insights into the factors limiting the performance of thick-film perovskite devices.
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Directly observing the chronology and tempo of adaptation in response to ecological change is rarely possible in natural ecosystems. Sedimentary ancient DNA (sedaDNA) has been shown to be a tractable source of genome-scale data of long-dead organisms1,2,3 and to thereby potentially provide an understanding of the evolutionary histories of past populations.4,5 To date, time series of ecosystem biodiversity have been reconstructed from sedaDNA, typically using DNA metabarcoding or shotgun sequence data generated from less than 1 g of sediment.6,7 Here, we maximize sequence coverage by extracting DNA from â¼50× more sediment per sample than the majority of previous studies1,2,3 to achieve genotype resolution. From a time series of Late Pleistocene sediments spanning from a marine to freshwater ecosystem, we compare adaptive genotypes reconstructed from the environmental genomes of three-spined stickleback at key time points of this transition. We find a staggered temporal dynamic in which freshwater alleles at known loci of large effect in marine-freshwater divergence of three-spined stickleback (e.g., EDA)8 were already established during the brackish phase of the formation of the isolation basin. However, marine alleles were still detected across the majority of marine-freshwater divergence-associated loci, even after the complete isolation of the lake from marine ingression. Our retrospective approach to studying adaptation from environmental genomes of three-spined sticklebacks at the end of the last glacial period complements contemporary experimental approaches9,10,11 and highlights the untapped potential for retrospective "evolve and resequence" natural experiments using sedaDNA.
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Ecossistema , Smegmamorpha , Animais , Adaptação Fisiológica/genética , Smegmamorpha/genética , Estudos Retrospectivos , LagosRESUMO
In two-dimensional/three-dimensional (2D/3D) perovskite heterostructure, randomly distributed multiple quantum wells (QW) 2D perovskites are frequently generated, which are detrimental to carrier transport and structural stability. Here, the high quality 2D/3D perovskite heterostructure is constructed by fabricating functional-group-induced single QW Dion-Jacobson (DJ) 2D perovskites. The utilization of âOCH3 in the precursor solution facilitates the formation of colloidal particles with uniform size, resulting in the production of a pure 2D DJ perovskite with an n value of 3. This strategy facilitates the improvement of 3D structural stability and expedites carrier transport. The resultant devices accomplish a power conversion efficiency of 25.26% (certified 25.04%) and 23.56% at a larger area (1 cm2 ) with negligible hysteresis. The devices maintain >96% and >89% of their initial efficiency after continuous maximum power point tracking under simulated AM1.5 illumination for 1300 h and under damp-heat conditions (85 °C and 85% RH) for 1010 h, respectively.
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This study aimed to investigate the expression levels of tissue and serum miR-149-3p and miR-149-5p in hospitalized patients with inflammatory bowel disease (IBD). A total of 35 ulcerative colitis (UC) patients, 12 Crohn's disease (CD) patients, and 25 healthy controls were included in the study. The miRNAs expressions were measured in tissue and serum samples using quantitative real-time polymerase chain reaction (qRT-PCR). Inflammatory biomarkers were measured, including serum albumin, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), and fecal calprotectin. MiR-149-3p and miR-149-5p were significantly decreased in the inflamed areas of both CD and UC patients compared to tissue controls, which was consistent with decreased serum levels in IBD patients compared to healthy controls. When distinguishing UC patients from healthy controls, serum miR-149-3p showed 74% sensitivity and 96% specificity, while serum miR-149-5p exhibited 63% sensitivity and 96% specificity. In the CD versus healthy control comparison, miR-149-3p achieved 100% sensitivity and 96% specificity, while miR-149-5p demonstrated 92% sensitivity and 96% specificity. In the UC versus CD comparison, miR-149-5p showed 75% sensitivity and 77% specificity, while miR-149-3p displayed 67% sensitivity and 80% specificity. Significant correlations were identified between the tissue and serum expression of miR-149-3p/5p and disease activity scores, as well as inflammatory biomarkers in both CD and UC patients. Decreased expression of miR-149-3p and miR-149-5p is associated with disease activity in IBD patients. These miRNAs demonstrate diagnostic potential and may serve as biomarkers for monitoring disease activity in IBD.
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Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , MicroRNAs , Humanos , Doenças Inflamatórias Intestinais/genética , MicroRNAs/metabolismo , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Doença de Crohn/genética , Doença de Crohn/diagnóstico , Biomarcadores , Gravidade do PacienteRESUMO
Cancer is one of the leading causes of death in the world. Invasive microscopic and endoscopic methods are not suitable for routine screening of gastric cancer. Therefore, the need for biomarkers that can detect quickly, efficiently, and with high sensitivity in the early stages of cancer is strongly felt. Stanniocalcin plays a role in regulating calcium and phosphorus in the body. In addition, it plays a role in neuron cell differentiation, angiogenesis, wound healing, fertility and embryo development, and cancer. This study investigated the level of expression of the Stanniocalcin 2 (STC2) gene in the serum of patients with gastric cancer. This case-control study was conducted on the samples of 60 patients with gastric cancer (cases) and 60 healthy individuals (controls). Peripheral blood samples from gastric cancer patients and volunteers as control groups were collected in tubes containing EDTA anticoagulant and were immediately subjected to serum separation. After centrifugation, serum RNA was extracted, and after cDNA synthesis, STC2 gene serum RNA level was measured by the Taq Man method and Real-time PCR using specific primers and probes. Then, the results of serum evaluations and clinicopathological information of patients and control group were collected along with the information obtained from reviewing patients' files and demographic findings, regulatory tables, and related charts. SPSS22 software was used to analyze descriptive data. According to the study results, the high expression of the STC2 gene was 31 cases in the case group and 13 cases in the control group. However, there was a significant relationship between the high expression of the STC2 gene and gastric cancer (p = 0.0001). However, there was no significant relationship between the gender of patients and high expression of the STC2 gene. However, the age of 35% of the patients was more than 65 years, and there was a significant relationship between the age of the patients and the high expression of the STC2 gene (P = 0.028). Although there was no significant relationship between the anatomical location of the cancer and the subtypes of the cancer and the high expression of the STC2 gene, there was a significant relationship between the degree of cancer differentiation and the high expression of STC2 gene (P<0.05). In general, STC2 can be used as a biomarker to determine the border and margins of the tumor. Analysis of STC2 gene expression during surgery can reduce surgical error in tumor removal and increase the success of surgery for tumor removal.
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RNA , Neoplasias Gástricas , Idoso , Humanos , Masculino , Estudos de Casos e Controles , Glicoproteínas/genética , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Soro , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologiaRESUMO
Solution-processed photodetectors have emerged as promising candidates for next-generation of visible-near infrared (vis-NIR) photodetectors. This is attributed to their ease of processing, compatibility with flexible substrates, and the ability to tune their detection properties by integrating complementary photoresponsive semiconductors. However, the limited performance continues to hinder their further development, primarily influenced by the difference of charge transport properties between perovskite and organic semiconductors. In this work, a perovskite-organic bipolar photodetectors (PDs) is introduced with multispectral responsivity, achieved by effectively managing charges in perovskite and a ternary organic heterojunction. The ternary heterojunction, incorporating a designed NIR guest acceptor, exhibits a faster charge transfer rate and longer carrier diffusion length than the binary heterojunction. By achieving a more balanced carrier dynamic between the perovskite and organic components, the PD achieves a low dark current of 3.74 nA cm-2 at -0.2 V, a fast response speed of <10 µs, and a detectivity of exceeding 1012 Jones. Furthermore, a bioinspired retinotopic system for spontaneous chromatic adaptation is achieved without any optical filter. This charge management strategy opens up possibilities for surpassing the limitations of photodetection and enables the realization of high-purity, compact image sensors with exceptional spatial resolution and accurate color reproduction.
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As a low-cost, low toxicity and metal-free catalyst with strong light absorption, graphitic carbon nitride (g-C3N4)-based materials have gained wide attention for efficient H2O2 photocatalysis. However, further investigation regarding the charge transfer process and reaction mechanism of H2O2 photoproduction remains to be completed. In this work, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTDA) modified g-C3N4 is synthesized through a facile one-step dehydration process, and the H2O2 photoproduction could reach 22.5 µmol within 8 hours. The proposed structure of g-BTDA is confirmed by FTIR, XPS and SEM studies. The transient absorption reveals a 20.88 ps charge transfer process caused by the electron withdrawing ability of the CîO group, and a 2-electron oxygen reduction pathway is proposed. Our work represents a new strategy for efficient H2O2 photoproduction using easily acquired materials with future application potential.
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Defects in the electron transport layer (ETL), perovskite, and buried interface will result in considerable nonradiative recombination. Here, a bottom-up bilateral modification strategy is proposed by incorporating arsenazo III (AA), a chromogenic agent for metal ions, to regulate SnO2 nanoparticles. AA can complex with uncoordinated Sn4+/Pb2+ in the form of multidentate chelation. Furthermore, by forming a hydrogen bond with formamidinium (FA), AA can suppress FA+ defects and regulate crystallization. Multiple chemical bonds between AA and functional layers are established, synergistically preventing the agglomeration of SnO2 nanoparticles, enhancing carrier transport dynamics, passivating bilateral defects, releasing tensile stress, and promoting the crystallization of perovskite. Ultimately, the AA-optimized power conversion efficiency (PCE) of the methylammonium-free (MA-free) devices (Rb0.02(FA0.95Cs0.05)0.98PbI2.91Br0.03Cl0.06) is boosted from 20.88% to 23.17% with a high open-circuit voltage (VOC) exceeding 1.18 V and ultralow energy losses down to 0.37 eV. In addition, the optimized devices also exhibit superior stability.
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Highly selective photoreduction of CO2 to valuable hydrocarbons is of great importance to achieving a carbon-neutral society. Precisely manipulating the formation of the Metal1 â â â C=Oâ â â Metal2 (M1 â â â C=Oâ â â M2 ) intermediate on the photocatalyst interface is the most critical step for regulating selectivity, while still a significant challenge. Herein, inspired by the polar electronic structure feature of CO2 molecule, we propose a strategy whereby the Lewis acid-base dual sites confined in a bimetallic catalyst surface are conducive to forming a M1 â â â C=Oâ â â M2 intermediate precisely, which can promote selectivity to hydrocarbon formation. Employing the Ag2 Cu2 O3 nanowires with abundant Cuâ â â Ag Lewis acid-base dual sites on the preferred exposed {110} surface as a model catalyst, 100 % selectivity toward photoreduction of CO2 into CH4 has been achieved. Subsequent surface-quenching experiments and density functional theory (DFT) calculations verify that the Cuâ â â Ag Lewis acid-base dual sites do play a vital role in regulating the M1 â â â C=Oâ â â M2 intermediate formation that is considered to be prone to convert CO2 into hydrocarbons. This study reports a highly selective CO2 photocatalyst, which was designed on the basis of a newly proposed theory for precise regulation of reaction intermediates. Our findings will stimulate further research on dual-site catalyst design for CO2 reduction to hydrocarbons.
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Solar-driven photocatalysis is a promising approach for renewable energy application. H2O2 photocatalysis by metal-free graphitic carbon nitride has been gaining attention. Compared with traditional thermal catalysis, metal-free graphitic carbon nitride photocatalysis could lower material cost and achieve greener production of H2O2. Also, to better guide photocatalyst design, a fundamental understanding of the reaction mechanism is needed. Here, we develop a series of model cost-effective metal-free H2O2 photocatalysts made from graphitic carbon nitride (melem) and common imide groups. With 4,4'-oxydiphthalic anhydride (ODPA)-modified g-C3N4, a H2O2 yield rate of 10781 µmol/h·g·L could be achieved. Transient absorption and ex situ Fourier transform infrared (FTIR) measurements revealed an ultrafast charge transfer from the melem core to water with â¼3 ps to form unique N-OH intermediates. The electron withdrawing ability of the anhydride group plays a role in governing the rate of electron transfer, ensuring efficient charge separation. Our strategy represents a new way to achieve a low material cost, simple synthesizing strategy, good environment impact, and high H2O2 production for renewable energy application.
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The shortage of narrow band gap polymer acceptors with high electron mobility is the major bottleneck for developing efficient all-polymer solar cells (all-PSCs). Herein, we synthesize a distannylated electron-deficient biselenophene imide monomer (BSeI-Tin) with high purity/reactivity, affording an excellent chance to access acceptor-acceptor (A-A) type polymer acceptors. Copolymerizing BSeI-Tin with dibrominated monomer Y5-Br, the resulting A-A polymer PY5-BSeI shows a higher molecular weight, narrower band gap, deeper-lying frontier molecular orbital levels and larger electron mobility than the donor-acceptor type counterpart PY5-BSe. Consequently, the PY5-BSeI-based all-PSCs deliver a remarkable efficiency of 17.77 % with a high short-circuit current of 24.93â mA cm-2 and fill factor of 75.83 %. This efficiency is much higher than that (10.70 %) of the PY5-BSe-based devices. Our study demonstrates that BSeI is a promising building block for constructing high-performance polymer acceptors and stannylation of electron-deficient building blocks offers an excellent approach to developing A-A type polymers for all-PSCs and even beyond.
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Non-covalent interactions play an essential role in directing the self-assembly of hybrid organic-inorganic crystals. In hybrid halide perovskites, hydrogen bonding has been the paramount non-covalent interaction. Here, we show another non-covalent interaction, namely, the halogen bond interaction, that directs a symmetry-breaking assembly in a new series of two-dimensional (2D) perovskites (ICH2 CH2 NH3 )2 (CH3 NH3 )n-1 Pbn I3n+1 (n is the layer thickness, n=1-4). Structural analysis shows that the halogen bond strength varies with the layer thickness. For the odd number (n=1, 3) layered perovskites, stronger halogen interaction leads to centrosymmetric structures, whereas for the n=2 layered perovskites, weaker halogen bonds result in non-centrosymmetric structures. Transient reflection spectroscopy shows a suppressed radiative recombination rate (k2 ≈0) and prolonged spin lifetime for n=2 structure, suggesting an enhanced Rashba band splitting effect. The structural asymmetry is further confirmed with a reversible bulk photovoltaic effect. Our work provides a new design strategy to enable hybrid perovskites with emerging properties and functionalities associated with structural asymmetry.
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A detailed picture of temperature dependent behavior of CsxFA1-xPbI3 perovskite quantum dots across the composition range is constructed by performing in situ optical spectroscopic and structural measurements, supported by theoretical calculations that focus on the relation between A-site chemical composition and surface ligand binding. The thermal degradation mechanism depends not only on the exact chemical composition, but also on the ligand binding energy. The thermal degradation of Cs-rich perovskite quantum dots is induced by a phase transition from black γ-phase to yellow δ-phase, while FA-rich perovskite quantum dots with higher ligand binding energy directly decompose into PbI2. Quantum dot growth to form large bulk size grain is observed for all CsxFA1-xPbI3 perovskite quantum dots at elevated temperatures. In addition, FA-rich quantum dots possess stronger electron-longitudinal optical phonon coupling, suggesting that photogenerated excitons in FA-rich quantum dots have higher probability to be dissociated by phonon scattering compared to Cs-rich quantum dots.
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Interfacial nonradiative recombination loss is a huge barrier to advance the photovoltaic performance. Here, one effective interfacial defect and carrier dynamics management strategy by synergistic modulation of functional groups and spatial conformation of ammonium salt molecules is proposed. The surface treatment with 3-ammonium propionic acid iodide (3-APAI) does not form 2D perovskite passivation layer while the propylammonium ions and 5-aminopentanoic acid hydroiodide post-treatment lead to the formation of 2D perovskite passivation layers. Due to appropriate alkyl chain length, theoretical and experimental results manifest that COOH and NH3 + groups in 3-APAI molecules can form coordination bonding with undercoordinated Pb2+ and ionic bonding and hydrogen bonding with octahedron PbI6 4- , respectively, which makes both groups be simultaneously firmly anchored on the surface of perovskite films. This will strengthen defect passivation effect and improve interfacial carrier transport and transfer. The synergistic effect of functional groups and spatial conformation confers 3-APAI better defect passivation effect than 2D perovskite layers. The 3-APAI-modified device based on vacuum flash technology achieves an alluring peak efficiency of 24.72% (certified 23.68%), which is among highly efficient devices fabricated without antisolvents. Furthermore, the encapsulated 3-APAI-modified device degrades by less than 4% after 1400 h of continuous one sun illumination.
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Here, we report a mixed GAI and MAI (MGM) treatment method by forming a 2D alternating-cation-interlayer (ACI) phase (n = 2) perovskite layer on the 3D perovskite, modulating the bulk and interfacial defects in the perovskite films simultaneously, leading to the suppressed nonradiative recombination, longer lifetime, higher mobility, and reduced trap density. Consequently, the devices' performance is enhanced to 24.5% and 18.7% for 0.12 and 64 cm2, respectively. In addition, the MGM treatment can be applied to a wide range of perovskite compositions, including MA-, FA-, MAFA-, and CsFAMA-based lead halide perovskites, making it a general method for preparing efficient perovskite solar cells. Without encapsulation, the treated devices show improved stabilities.
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Singlet fission is a process by which an organic semiconductor is able to generate two triplet excitons from a single photon. If charges from the triplets can be successfully harvested without heavy losses in energy, then this process can enable a single-junction solar cell to surpass the Shockley-Queisser limit. While singlet fission processes are commonly observed in several materials, harvesting the resulting triplets is difficult and has been demonstrated with only a few transport materials. Here, transient absorption spectroscopy is used to investigate singlet fission and carrier transfer processes at the AgBiS2 /pentacene (AgBiS2 /Pc) heterojunction. The successful transfer of triplets from pentacene to AgBiS2 and the transfer of holes from AgBiS2 to pentacene is observed. Further singlet fission in pentacene by modifying the crystallinity of the pentacene layer and have fabricated the first singlet fission AgBiS2 /Pc solar cell is enhanced. Singlet fission devices exhibit higher external quantum efficiency compared with the control devices, and thus demonstrating the significant contribution of charges from the singlet fission process.