Passive Strategies Research Articles

Flexible Narrow Bandgap Sn-Pb Perovskite Solar Cells with 21% Efficiency Using N,N'-Carbonyldiimidazole Treatments.

Flexible tin-lead (Sn-Pb) mixed perovskite solar cells (PSCs) are among the promising flexible photovoltaics, owing to the narrow bandgap (NBG) of Sn-Pb perovskites, flexible and wearable features, and their role as a critical component in all-perovskite tandem photovoltaics. However, the flexible Sn-Pb PSCs suffer from a low power conversion efficiency, no higher than 18.5%, along with limited stability. Herein, we reported an efficient and stable flexible NBG Sn-Pb PSC via an N,N'-carbonyldiimidazole (CDI) passivation strategy. CDI, with strong adsorption energy, preferentially binds to Sn2+ compared with oxygen (O2), thus effectively inhibiting the adsorption of O2 on perovskite surfaces. The transfer of electron density around Sn2+ dramatically decreased, thus suppressing Sn2+ oxidation. The CDI treatments endowed the Sn-Pb mixed films with fewer defects, improved crystallinity, better morphology, and matched energy-level alignment. The flexible Sn-Pb devices exhibited a high PCE of 21.02%. Besides, the devices showed enhanced stability and promoted flexibility. This work provides a pathway to visibly increase the efficiency and stability of the flexible Sn-Pb mixed photovoltaic cells.

Evaluating robo-advisors through behavioral finance: a critical review of technology potential, rationality, and investor expectations

The mini review assesses the value propositions of robo-advisors through the lens of behavioral finance. Despite their promise of data-driven, rational investment strategies, robo-advisors may not fully replicate the personalized service of human financial advisors or eliminate human biases in decision-making. A content analysis of 80 peer-reviewed articles and publications was conducted, focusing on the intersection of financial technology and behavioral finance. Literature was retrieved using The Chicago School University Library's OneSearch and the EBSCO host database, with key terms including “robo-advisor,” “investment behavior,” “risk tolerance,” “financial literacy,” and “affective trust.” The review identifies four key limitations of robo-advisors: (1) their inability to replicate the service-relationship of human advisors; (2) the presence of human bias in supposedly rational algorithms; (3) the inability to minimize market risk; and (4) their limited impact on improving users' financial literacy. Instead, robo-advisors temporarily compensate for a lack of financial knowledge through passive investment strategies. The findings suggest that integrating behavioral finance principles could enhance the predictive power of robo-advisors, though this would introduce additional complexities. The review calls for further research and regulatory measures to ensure that these technologies prioritize investor protection and financial literacy as they continue to evolve.

Backyard flock sampling and artificial intelligence: A dual strategy for early detection of Avian Influenza and Newcastle Disease

Avian Influenza (AI) and Newcastle Disease (ND) are significant avian diseases that pose substantial threats to the commercial poultry industry due to their high contagion rates and potential for severe outcomes. Recent shifts in the epidemiology and ecology of both viruses have led to devastating impacts on wild bird and poultry populations, as well as farms and communities worldwide. These challenges underscore the necessity for One Health approaches to pandemic prevention and preparedness, emphasizing the need for multisectoral collaboration among animal, environmental, and public health sectors. To mitigate future pandemic risks, it is essential to control the transmission of AI and ND viruses among domestic and wild animals as well as humans. This involves addressing the upstream drivers of outbreaks, ensuring rapid response mechanisms, and conducting thorough risk assessments for zoonotic diseases. Effective implementation and maintenance of prevention programs, surveillance, and outbreak responses require strong political commitment and sustainable funding. A robust combination of active and passive surveillance strategies should be applied to monitor and control them. In addition, the integration of modern technologies, such as artificial intelligence and big data analytics, can enhance both active and passive surveillance efforts by improving the accuracy and speed of data collection, analysis, and reporting. The use of backyard flocks as an early warning system for avian diseases represents a proactive approach to understanding and managing the risks associated with AI and ND through targeted surveillance and timely interventions. In response to these challenges, the EpirORNIS Project aimed to leverage these sentinel backyard flocks for early detection of AI and ND, thereby enhancing surveillance and control strategies.

Strategies to improve recruitment to multimodal group programmes for obesity: a systematic review

Abstract Background The World Health Organization describes obesity as one of the greatest public health challenges in the 21st century. Possible therapies include multimodal (group) programmes with nutrition, exercise, and behavioural therapy elements. However, programme providers often have difficulties recruiting the target groups and motivating them to participate. This systematic review aimed to identify barriers and facilitators as well as strategies to improve recruitment. Methods We systematically searched five databases (Medline, CINAHL, Cochrane, PsycInfo, Web of Science). Based on predefined inclusion criteria, we selected primary studies of different study designs (e.g. [randomised] controlled trials, qualitative studies). We extracted barriers and facilitators as well as recruitment strategies into predefined tables, assessed the quality of the studies and summarised the results narratively. Results Of the 1,082 articles identified, 16 met the inclusion criteria. The main active recruitment strategies were writing directly to potential participants and referrals from health professionals. The most frequently reported passive strategies included media adverts, websites, flyers, social media, and word of mouth. The information on how many people approached actually participated was heterogeneous, which illustrates that recruitment depends on the setting/context and the people involved. Some studies came to contradictory results, e.g., regarding whether passive or active methods are more successful. In most cases, a combination of strategies was recommended. The studies reported numerous recruitment barriers, e.g., lack of staff time, lack of motivation, or fear of discrimination. Conclusions The review provides a broad overview of recruitment methods that can be applied depending on the framework conditions and target groups. The summary of possible barriers can serve as an overview of which aspects could be considered when designing or adapting a programme. Key messages • To improve recruitment to obesity programmes, a combination of several recruitment strategies, including active and passive methods, should be applied. • Results on the “effectiveness” of the strategies were inconclusive, which indicates that the success of methods depends on the context, setting and the people involved.

Synergistic Passivation of Bulk and Interfacial Defects Improves Efficiency and Stability of Inverted Perovskite Solar Cells

Defects both in bulk and at the interfaces serve as charge trapping sites for nonradiative recombination and as ion migration pathways, resulting in degradation of perovskite solar cell efficiency and stability. In this work, a strategy for simultaneous passivation of both bulk and interfacial defects is reported. For bulk passivation polystyrene (PS) is used as an additive in the perovskite precursor which reduces the structural defects by forming larger defect‐free grains. While the F‐PEAI cation is used to passivate the interfacial defects, present at both perovskite HTL/ETL interfaces. Furthermore, by conducting control measurements with just bulk modification (PS), just interface modification (F‐PEAI), and a combination of both, the role of individual defect passivation strategies is decoupled. As a result of simultaneous bulk as well as interfacial passivation, the modified perovskite solar cell shows the highest efficiency of 22.32% with a high Voc of 1.14 V and fill factor of 80%. Moreover, the cells have excellent stability retaining 92% and 99% of their initial efficiency after 1008 h and 560 h under ISOS‐ D1 and D2 storage conditions. These results highlight the importance of simultaneous bulk and interfacial passivation for improving solar cell efficiency and stability.

High-Performance CuInS2 Quantum Dot Sensitized Solar Cells Through I-/MPA Dual-Ligands Passivation.

High-efficiency quantum dot sensitized solar cells (QDSSCs) can be received by increasing quantum dot (QD) loading and mitigating QD surface trap states. Herein, the surface state of CuInS2 QDs is optimized through an I-/MPA dual-ligands passivation strategy. The steric hindrance and electrostatic repulsion between QDs can be effectively reduced, thereby enabling an increased QD loading capacity. Meanwhile, the I-/MPA dual-ligands passivation strategy can further lower the surface trap density, leading to substantially enhanced charge transfer efficiency of the solar cells. Interestingly, various iodized salts, including TBAI, MAI, and KI, are proved to possess comparable property, underscoring the versatility and broad applicability of this I-/MPA dual-ligands passivation strategy. Eventually, CuInS2 QDSSCs based on the NH4I/MPA dual-ligands exhibit a noteworthy enhancement in photovoltaic conversion efficiency, surpassing the benchmark of 5.71 % to reach 7.03 %.

Sustainable drag reduction in Taylor-Couette flow using riblet superhydrophobic surfaces

Superhydrophobic surfaces (SHSs) have been proven effective in reducing frictional drag force in various flow conditions. However, at high flow speeds, the air plastron on these surfaces collapses, leading to a decline in their effectiveness. In this study, we investigated the frictional drag forces of various SHSs and their combination with surface patterns across a wide range of flow conditions (5.00×102 < Re < 1.12×105) by using an facile coating method. Our experiments involved incorporating a superhydrophobic coating on the inner cylinder of a custom-made Taylor-Couette apparatus, integrated with a rheometer to measure torque applied on the inner rotor as a function of rotational speed. As part of our research, we calculate the effective slip length to assess the drag reduction performance of coatings, revealing an effective slip length of around 63 µm on a flat SHS. Furthermore, we explore the combined effect of superhydrophobic coatings and triangular-shaped riblets on drag reduction in Taylor-Couette flow, comparing the performance of these surfaces based on the riblet’s sharpness and the Reynolds number. Our experimental results show a reduction in measured torque of up to 24 % and 48 % on a V-grooved SHS in laminar and turbulent flow, respectively. Longevity tests confirm that the designed surfaces maintain their superhydrophobicity and drag reduction performance under turbulent flow conditions. Overall, this work introduces a passive drag reduction strategy through surface design, which substantially mitigates the frictional drag force and demonstrating considerable potential for enhanced performance and increased efficiency of Taylor-Couette systems.

Influence of Substrate on Sb2Se3/CdS Heterojunction Thin Film Solar Cells and Evaluation of Their Performance by Dark J‐V Analysis

ABSTRACTA simple binary antimony selenide (Sb2Se3) absorber is evolving as an alternative photovoltaic material in thin film solar cells because of its unique properties and easy processing. Sb2Se3 thin films having good crystalline quality are grown via versatile thermal evaporation from pre‐synthesized near stoichiometric compound material on molybdenum‐coated soda lime glass (SLG) and borosilicate glass (BG) substrates. Following the systematic characterizations on the absorber films, substrate configured Sb2Se3/CdS heterojunction devices were fabricated and their photovoltaic characteristics have been studied using current density vs. voltage (J‐V), dark J‐V modeling, external quantum efficiency and capacitance vs. voltage measurements. The power conservation efficiency values of 4.88% and 5.04% were achieved for the devices fabricated on SLG and BG substrates, respectively with deficit in open circuit voltage. The obtained values are higher in comparison to the reported device efficiencies in substrate configured Sb2Se3 solar cells, in which the absorber is prepared through thermal evaporation. To understand the loss in open circuit voltage, a compact equivalent circuit model was considered and identified the contribution of different shunt leakage paths in the devices. In addition to that, the device fabricated on the SLG was stable with minimal changes in its photovoltaic performance for a period spanning over 200 days. The results obtained are encouraging with scope for improving the device performance through interface engineering and back surface passivation strategies.

To Act or Wait: The Impact of Disruption Duration Estimates on Manufacturer’s Response Strategies

In the event of a disruption at a primary supplier, the manufacturer’s sourcing and production operations are inevitably affected, necessitating a response strategy based on the estimated disruption duration. This paper derives the optimal production policy for each response strategy, aiming to minimize total costs over a planning horizon within a dynamic programming framework. We characterize these production policies across various model parameters, particularly focusing on the estimated disruption duration and initial inventory level. Our analysis identifies when the passive acceptance strategy and the backup strategy each hold an advantage, and how the cost benefits of each strategy vary with different model parameters. Additionally, we examine the consequences of overestimating or underestimating the disruption duration, providing insights into how the chosen response strategy and production policy, based on the estimated duration, diverge from the true optimal ones as the actual duration unfolds. We also highlight the cost implications of these discrepancies. Finally, in scenarios where the true duration follows a probabilistic distribution, our numerical experiments demonstrate how strategy selection and the cost of misestimation are influenced by the mean of the true disruption duration and the initial inventory level. These analyses offer decision-makers valuable guidance on when to act or wait in the face of disruptions.

Research on a Bridge Hybrid Isolation Control System Based on PID Active Control and Genetic Algorithm Optimization

A bridge hybrid isolation system, integrating both active and passive control strategies, is proposed and investigated to enhance seismic performance. The system is modeled as a two-layer structure, with the upper layer subjected to active control via a Proportional–Integral–Derivative (PID) controller, and the lower layer employing a conventional passive base isolation system. The displacement response of the superstructure is minimized by the control forces generated by the PID controller, which also accounts for the reaction forces transmitted to the lower isolation layer. To optimize the controller’s performance, a genetic algorithm is implemented for real-time tuning of the PID parameters. Numerical simulations, conducted using the Newmark method, are employed to assess the influence of active control on the lower isolation system. The results reveal that, while active control increases the peak displacement of the superstructure to some extent, it significantly prolongs the structural period, thus enhancing the system’s overall seismic resilience and stability.

Long-term corrosion protection of reinforcing bars via a self-responsive coating incorporating ZrP functional fillers

The conventional coating of reinforcing bars exhibits inadequate anti-corrosion efficacy stemming from a non-specific, blind protection mechanism, poses a threat to the durability of concrete. We devised a novel self-responsive functional filler, L-arginine (LA) intercalated zirconium phosphate (LCZrP), synthesized via an intercalation reaction. This innovative filler was seamlessly integrated into an epoxy (EP) resin matrix, yielding a smart anticorrosive coating that harmoniously combines active and passive corrosion protection strategies. The integration of LCZrP within the coating matrix serves a trifecta of purposes: it extends the corrosion propagation path, effectively disperses nanofiller agglomeration, and enhances interfacial adhesion with the epoxy coating. Critically, the controlled release of corrosion inhibitors from the interlayer further fortifies the coating's resistance to corrosion, imparting a multi-layered protective shield. After enduring a 60-day immersion in a simulated concrete pore solution, the LCZrP/EP coating demonstrated exceptional durability, maintaining a low-frequency impedance modulus value consistently within the range of 4.27×1010 to 5.12×1010 Ω·cm2, marking a remarkable 34-fold enhancement over the performance of the epoxy coating alone. This breakthrough underscores the LCZrP/EP coating's potential as a groundbreaking solution for reinforcing bar protection in concrete, harnessing the complementary strengths of epoxy resin's physical barrier, the impermeability of two-dimensional lamellar structures, and the proactive release of corrosion inhibitors to forge a robust, multi-faceted passivation layer.

Sustainable Logistics: Synergizing Passive Design and PV–Battery Systems for Carbon Footprint Reduction

As more companies strive for net-zero emissions, mitigating indirect greenhouse gas emissions embedded in value chains—especially in logistics activities—has become a critical priority. In the European logistics sector, sustainability and energy efficiency are receiving growing attention, given the sector’s intersectional role in both transportation and construction. This transition toward low-carbon logistics design not only reduces carbon emissions but also yields financial benefits, including operational cost savings and new market opportunities. This study examines the impact of passive design strategies and low-carbon technologies in a Swedish logistics center, assessed using the low-carbon design criteria from the BREEAM International standard, version 6. The findings show that passive energy-efficient measures, such as the installation of 47 skylights for natural daylighting, reduced light power density in accordance with AHSHARE 90.1-2019 and the integration of free night flushing, contribute to a 23% reduction in total energy consumption. In addition, the integration of 600 PV panels and 480 batteries with a capacity of 268 ampere-hours and 13.5 kWh storage, operating at 50 volts, delivers a further 56% reduction in carbon emissions. By optimizing the interaction between passive design and active low-carbon technologies, this research presents a comprehensive feasibility analysis that promotes sustainable logistics practices while ensuring a future-proof, low-carbon operational model.

Live Survival Strategy to Grow Entrepreneurial Interest in the Perspective of Maqashid Asy-Syari'ah (On Deaf-Mute Disabilities UPT RSBRW - Pasuruan)

Difficulties for people with hearing and speech impairments in accessing formal employment because companies only open and look for workers in the physically &amp; mentally healthy category, to increase productivity &amp; effectiveness of employee performance. While getting a job is very important &amp; fundamental for sustainability &amp; continuity. One of the problems faced by people with hearing impairments is how to develop skills &amp; knowledge according to their talents and interests, so that they are able to move independently in fulfilling and prospering their needs &amp; desires without depending on the informal sector.This research is descriptive research with a qualitative approach. The researcher will describe survival strategies to foster interest in entrepreneurship for people with hearing and speech impairments according to field conditions with the aim of finding a comprehensive survival strategy formulation. From the results of data analysis in the field, it is clear that the concept of success in the presence of limitations / impairments is that there are 3 types of survival strategies used by people with hearing and speech impairments, namely: active strategy (having, independence, confidence, enthusiasm, optimism, perseverance), passive strategy (making savings in meeting needs: dharuriyat, hajiyat, tahsiniyat, and implementing rational consumption patterns/ mustahlik al-aqlani), network strategy (using available accessibility &amp; building relationships with related agencies).

Phototheranostic LPP-QDs-IR-820 Nanocomposites for Specific NIR-II Imaging of Lymphatic and Photothermal Therapy of Cervical Tumors.

Precise theranostics of tumors is intricately linked to the early detection and monitoring of lymph nodes (LN) and metastases, making the targeted localization of LNs essential for tumor identification. However, designing LN-targeting probes remains a significant challenge due to issues such as lymphatic uptake, biocompatibility, and fluorescence stability. To address these challenges, near-infrared II (NIR-II) fluorescence probes are developed through meticulous analysis of LN physiological structure and passive targeting strategy for LN detection and tumor therapy. An LPP-QDs-IR-820 nanocomposite (NCs) is engineered, comprising the IR-820 molecules and ultrabright PbS@CdS quantum dots (QDs), which are encapsulated within a liposome-SH-mPEG2000 polymer matrix. These NCs demonstrates remarkable lymphatic enrichment, facilitating real-time tracking of LN via electrostatic repulsion and extracellular matrix effects. Importantly, the NCs exhibit negligible in vivo toxicity and high biocompatibility. The intense NIR-II fluorescence emissions of IR-820 and PbS@CdS QDs confer upon the NCs a high NIR-II fluorescence quantum yield (6%). The cervical tumors and their deep microvessels are clearly observed via NIR-II fluorescence imaging. Moreover, the photothermal properties of IR-820 enable the NCs to achieve a photothermal conversion efficiency of 36.56%, leading to effective photothermal therapy in cervical tumor mice.

Isomeric diammonium passivation for perovskite-organic tandem solar cells.

In recent years, perovskite has been widely adopted in series-connected monolithic tandem solar cells (TSCs) to overcome the Shockley-Queisser limit of single-junction solar cells. Perovskite/organic TSCs, comprising a wide-bandgap (WBG) perovskite solar cell (pero-SC) as the front cell and a narrow-bandgap organic solar cell (OSC) as the rear cell, have recently drawn attention owing to the good stability and potential high power conversion efficiency (PCE)1,2,3,4. However, WBG pero-SCs usually exhibit higher voltage losses than regular pero-SCs, which limits the performance of TSCs5,6. One of the major obstacles comes from interfacial recombination at the perovskite/C60 interface, and it is important to develop effective surface passivation strategies to pursue higher PCE of perovskite/organic TSCs7. Here we exploit a new surface passivator cyclohexane 1,4-diammonium diiodide (CyDAI2), which naturally contains two isomeric structures with ammonium groups on the same or opposite sides of the hexane ring (denoted as cis-CyDAI2 and trans-CyDAI2, respectively), and the two isomers demonstrate completely different surface interaction behaviors. The cis-CyDAI2 passivation treatment reduces the Quasi-Fermi level splitting (QFLS)-open circuit voltage (Voc) mismatch of the WBG pero-SCs with a bandgap of 1.88 eV and enhanced its Voc to 1.36 V. Combining the cis-CyDAI2 treated perovskite and the organic active layer with a narrow-bandgap of 1.24 eV, the constructed monolithic perovskite/organic TSC demonstrates a PCE of 26.4% (certified as 25.7%).

An Overview of the Effects of Passive Solar Strategies on Thermal Comfort

The paper presents the impact of passive solar strategies on residential buildings concerning the thermal comfort factor. This study focuses on passive solar design elements like orientation, shading, and thermal mass to offer improved energy efficiency and occupant comfort. With a global natural gas crisis looming, interest in alternative heating and cooling is surging. With the growing concern of reducing the energy use by buildings while maintaining proper thermal comfort, both in cold and hot climates, the interest shifts to passive solar strategies. In this view, 547 publications have been analysed to reveal knowledge gaps and trends in the research. The bibliographic and thematic analysis techniques identified some approaches to passive solar design but no dominant method. Further, the study found under-researched areas within themes that appeared established. The authors have finally concluded with calls for further research and collaboration across institutions and nations to address these gaps and develop effective passive solar strategies. These findings contribute to sustainable architecture by pointing out the pros of applying passive solar strategies to reduce heating and cooling loads. In this respect, this was an original approach since it brought both quantitative and qualitative data together to measure thermal comfort. This is further underpinned by raising the need for energy-efficient building designs as measures toward mitigating climate change impacts.

Accumbal Dopamine Responses Are Distinct between Female Rats with Active and Passive Coping Strategies.

There is a gap in existing knowledge of stress-triggered neurochemical and behavioral adaptations in females. This study was designed to explore the short-term consequences of a single social defeat (SD) on accumbal dopamine (DA) dynamics and related behaviors in female Wistar rats. During the SD procedure, rats demonstrated different stress-handling strategies, which were defined as active and passive coping. The "active" subjects expressed a significantly higher level of activity directed toward handling stress experience, while the "passive" ones showed an escalated freezing pattern. Remarkably, these opposite behavioral manifestations were negatively correlated. Twenty-four hours following the SD exposure, decreased immobility latency in the Porsolt test and cognitive augmentation in the new object recognition evaluation were evident, along with an increase in electrically evoked mesolimbic DA release in passive coping rats. Rats exhibiting an active pattern of responses showed insignificant changes in immobility and cognitive performance as well as in evoked mesolimbic DA response. Furthermore, the dynamics of the decline and recovery of DA efflux under the depletion protocol were significantly altered in the passive but not active female rats. Taken together, these data suggest that female rats with a passive coping strategy are more susceptible to developing behavioral and neurochemical alterations within 24 h after stress exposure. This observation may represent both maladaptive and protective responses of an organism on a short timescale.

Enhanced surface acoustic wave microfluidic performance through FDTS self-assembled monolayers on [formula omitted]

Microfluidics technology has been extensively applied in biochemical analysis and medical diagnostics, where precise and efficient control of microfluids is crucial. However, existing passive microfluidic control methods (e.g., microchannels) and active strategies (e.g., optical, thermal, magnetic field, and electrokinetic manipulation) are often hindered by complex device structures and operational uncertainties. Surface acoustic wave (SAW) microfluidic manipulation offers a promising alternative, providing flexible and efficient digital microfluidic control through the modulation of input signals. Nevertheless, the intrinsic hydrophilicity of substrates such as LiNbO3 results in inefficient microfluidic driving and jetting, primarily due to high surface tension. In this study, we employed chemical vapor deposition (CVD) to coat LiNbO3 substrates with 1H,1H,2H,2H-Perfluorododecyltrichlorosilane (FDTS) self-assembled monolayers (SAMs), creating hydrophobic surfaces with a contact angle of approximately 120°. In comparison to commercially available Glaco hydrophobic coatings, which reduce SAW amplitude by approximately threefold and increase substrate temperature by up to 1.5 times, FDTS SAMs exhibit negligible impact on SAW properties. Furthermore, when compared to untreated SAW devices, FDTS SAMs-coated devices demonstrated a sixfold increase in droplet driving speed under low power input (e.g., 0.5 W), enabling faster and more precise liquid jetting at velocities reaching 5 m/s. This work highlights the potential of FDTS SAMs in enhancing the performance of SAW-driven microfluidic devices, particularly in applications requiring high-efficiency droplet manipulation.

Intelligent vibration control of tensile cable based on deep reinforcement learning

Vibration of tensile cables commonly occurs in the engineering structures such as cable-stayed bridges, which may have negative effect on the driving comfort and safety, and further lead to the fatigue problems of the structure. This paper proposes a semi-active control strategy based on deep reinforcement learning and magneto-rheological (MR) damper, for the vibration control of tensile cables, and the corresponding algorithm have been developed. Through the interaction with the cable-damper system, the intelligent agent can evaluate every possible control parameter and achieve an effective control policy. Then, according to the real-time vibration state, the agent would determine an action current for the MR damper and thus change the damping coefficient of the damper, further make influences on the vibrating cable. Basically, the proposed strategy realizes the model-free semi-active control of cable vibrations. To validate the effectiveness of the proposed semi-active control strategy, a scale model test has been conducted, where the test cases of passive and semi-active control strategies are carried out and compared. Results show that, the semi-active control shows a prior performance in vibration reduction compared to the passive control strategy, with regard to the vibration profile, the vibration energy, as well as the energy dissipation of MR damper.

An Eco-Friendly Passivation Strategy of Resveratrol for Highly Efficient and Antioxidative Perovskite Solar Cells.

The stability of perovskite solar cells is closely related to the defects in perovskite crystals, and a large number of crystal defects are caused by the solution method. In this study, resveratrol (RES), a green natural antioxidant abundant in knotweed and grape leaves, is introduced into perovskite films to passivate the defect. RES achieves defect passivation by interacting with uncoordinated Pb2+ in perovskite films. The defect formation energy of VPb and PbI on the surface of perovskite thin films is increased by RES doping, as calculated by density functional theory. The results show that the quality of the perovskite film is significantly improved, and the energy level structure of the device is optimized, and the power conversion efficiency (PCE) of the device is increased from 21.62% to 23.44%. RES can hinder the degradation of perovskite structures by O2 - free radicals, and the device retained 88% of its initial PCE after over 1000 h in pure oxygen environment. The device retains 91% of the initial PCE after >1000 h at 25°C and 50 ± 5% relative humidity. This work provides an idea for the use of natural and environmentally friendly additives to improve the efficiency and stability of devices.