Minimal Defects Research Articles

Influence of process parameters on magnetic abrasive machining efficiency

The development of modern mechanical engineering forces us to constantly improve the technology of processing materials and look for ways not only to improve the quality of products but also to increase the efficiency of the processing process itself. This article discusses an alternative method to finish the product, which can replace the traditional method of grinding, magnetic abrasive treatment. This is a modern solution that allows you to obtain high surface quality of the processed product with minimal defects in their surface layer, and reduce the number of technological operations, which has a beneficial effect on the efficiency of the processing process. The efficiency of the magnetic abrasive machining process, which was determined by the amount of specific removal of the material, is influenced by many parameters, some of which were studied in this article: electromagnetic induction and processing time. The success of the application of magnetic abrasive treatment can also be judged by the topography of the surface of the product made using an electron microscope. The data obtained in the course of the study demonstrated the importance of individual input parameters of the magnetic abrasive treatment process in the formation of the surface layer of the product. According to the results of experimental studies, the dependences of the varied parameters were determined and recommendations were formed to improve the efficiency of the use of the magnetic abrasive process.

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PREVALENCE OF BODY DYSMORPHIC DISORDER AMONG FEMALE PATIENTS SEEKING COSMETIC PROCEDURES

Body dysmorphic disorder (BDD) is a psychiatric illness in which individuals with minimal or non-existent defects related to appearance worry immensely about their looks:which results in displaying significant distress and impairment in behavior and psychosocial functioning. Patients with BDD seeking cosmetic surgery are usually unsatisfied with the outcomes of the surgery. Therefore, it is important to study this phenomenon and increase awareness among physicians about the importance of assessing their patients before starting any cosmetic treatment. To assess the presence of BDD in patients undergoing cosmetic procedures, and to improve the awareness about BDD among providers of cosmetic treatment. This is a cross-sectional study that uses the adult version of the BDD modification of the Y-BOCS (BDD-YBOCS) scale. This scale consists of 12 items related to preoccupied thoughts that participants have about their appearance, and the effects that these thoughts have on their lives. In this study, participants were instructedto answer questions on a 5-point Likert-type scale. Questionnaires were distributed on different online platforms, among females living in the eastern province of Saudi Arabia. Out of these, responses were received from 220participants. Out of the 220 women who participated in this cross-sectional study, 45 of them had BDD (prevalence rate of 20.5%), which is a significant percentage. The results of the study indicate that BDD is more prevalent among participants in the age group of 20–35 years. The study also revealed that a positive correlation exists between BDD and females seeking cosmetic procedures. we found thatOne-fifth of the participants were diagnosed to be suffering from BDD. Higher rates of BDD were observed among women who underwent cosmetic procedures. Therefore, we recommend physicians to conduct a BDD screening for patients seeking cosmetic procedures before treatment.

Fused silica with sub‐angstrom roughness and minimal surface defects polished by ultrafine nano‐CeO2

AbstractSurface quality of fused silica, particularly surface defect and surface roughness, is a key factor affecting the performance of high‐power laser and short‐wave optical instrument, and so on. Herein, the super smooth surface of fused silica with roughness of sub‐angstrom level and exceedingly few submicron defects was achieved by using ultrafine nano‐CeO2 with primary particle size less than 4 nm, low secondary particle agglomeration strength, and high Ce3+ concentration. Furthermore, CeO2 involve in polishing process in the form of primary particle was certified by experiment. Moreover, the cause for the generation of submicron defects on fused silica surface was investigated for the first time from the perspective of secondary particle agglomeration strength of CeO2. The concentration of Ce3+ in CeO2 was characterized by the redshift of the band‐gap energy, and the analysis of material removal rate (MRR) and contact angle of polished fused silica shows that Ce3+ enhances MRR through increasing the silanol group on fused silica.

PES/ZIF‐L mixed‐matrix membrane for CO2 permeation: Influence of ionic liquid in pre‐ and post‐modification treatment

AbstractIt is known that mixed‐matrix membranes (MMMs) suffer from poor compatibility between the polymer and inorganic phases. As a result, suboptimal morphology of a membrane is obtained. This study fabricated MMMs containing ZIF‐L as the inorganic filler and polyethersulfone (PES) via the thermally induced phase separation method. ZIF‐L loading was varied from .25 to 10.0 wt% to study the effect of ZIF‐L loading on the characteristic of the MMMs and gas separation performance (CO2/N2 and CO2/CH4). Unmodified ZIF‐L resulted in significant permeability and selectivity trade‐offs. To improve the compatibility between the components and affinity towards CO2, ionic liquid (IL) was introduced. Two methods of IL modification methods were tested. They are pre‐modification of ZIF‐L and post‐modification of PES/ZIF‐L MMMs. The findings revealed that the pre‐modification method has successfully sealed the polymer/filler interfacial void compared to post‐modification. It was found that the pre‐modification method has enhanced PES/ZIF‐L membrane's performance due to the minimal interfacial defects issue at low loading; 0.75 wt% of pre‐modified ZIF‐L in the PES matrix has enhanced the permeability of CO2 by more than eight times. Furthermore, the ideal CO2/N2 and CO2/CH4 selectivity recorded at this condition is 30.1 and 21.8, respectively. On the contrary, the post‐modification strategy turns out to be counterproductive.

Additively manufactured Haynes-282 monoliths containing thin wall struts of varying thicknesses

Magnitude and distribution of residual stresses in additively manufactured Ni-based superalloys may impact the mechanical performance of as-fabricated parts. Though electron beam powder bed fusion (E-PBF) can produce components with minimal defects and residual stresses compared to laser powder bed fusion and directed energy deposition, variations of them may occur within the complex geometry of a component, due to inherent variations of thermal signatures and the evolution of section modulus along the build direction. This work reveals the residual stress distribution, characterised from neutron diffraction, of an as-fabricated Haynes 282 monolith containing internal cube voids and thin wall struts of varying thicknesses. Complementary local hardness measurements and multi-scale microscopy were used to investigate the geometry-structure-property relationships. Observed variations in hardness were attributed to a combination of type I macro-scale residual stresses and variations in bimodal γ′ precipitation behaviour. The results highlight the influence of residual stresses and microstructure on the mechanical properties of E-PBF Haynes 282.

Modified Fabrication of Perovskite-Based Composites and Its Exploration in Printable Humidity Sensors.

Organic perovskites are promising optoelectronic semiconductor materials with photoelectric applications. It is known that the luminescence of perovskites is highly sensitive to hydron molecules due to its low moisture resistance of crystal structure, indicating its potential application on humidity-sensing. Herein, a novel perovskite-based compound (PBC) with minimal defects was developed to promote the photoluminescence performance via optimization of the drying method and precursor constitutions. Perovskite materials with good structural integrity and enhanced fluorescence performance up to four times were obtained from supercritical drying. Moreover, the hydrophilic polymer matrix, polyethylene oxide (PEO), was added to obtain a composite of perovskite/PEO (PPC), introducing enhanced humidity sensitivity and solution processibility. These perovskite/PEO composites also exhibited long-term stability and manifold cycles of sensitivity to humidity owing to perovskite encapsulation by PEO. In addition, this precursor solution of perovskite-based composites could be fancily processed by multiple methods, including printing and handwriting, which demonstrates the potential and broaden the applications in architecture decoration, logos, trademarks, and double encryption of anti-fake combined with humidity.

Sustainable Machining of Mg-9Al-1.4Zn Foam Used for Temporary Biomedical Implant Using Cryogenic Cooling.

In this study, the drilling performance of biodegradable grade Mg-9Al-1.4Zn alloy reinforced with hollow thin-walled Al2O3 microspheres is inspected under different coolant environments such as dry, Almag® mineral oil, and liquid nitrogen. Drilling experiments were carried out using titanium aluminum nitride PVD coated and uncoated K10 tools on varying volume fractions of magnesium syntactic foams (5%, 10%, and 15%) reinforced with hollow Al2O3 microspheres. Test results showed a 30–60% higher thrust force generated with liquid nitrogen drilling in comparison to dry and oil-based drilling while cutting higher volume fraction foams. Higher microsphere volume fractions of syntactic foam recorded higher machining forces, which is roughly a 200% increase as the volume fraction raised to 15%. The performance of TiAlN PVD tool coating is reflected through a reduction in thrust forces by 20% during cryogenic drilling. Scanning electron microscope (SEM) investigation of cryogenic-machined bore surfaces showed minimal drilling-induced surface defects compared to dry and Almag® mineral oil conditions. A three-dimensional, thermo-mechanical finite element-based model for drilling Mg-9Al-1.4Zn syntactic foam using AdvantEdgeTM is developed for different sustainable lubrication conditions. Surface finish (Ra) showed a 45–55% improvement during cryogenic drilling of 15% syntactic foams with minimized subsurface damages compared to dry and wet cutting conditions. The higher the volume fraction, the higher the surface roughness (Ra) and thrust force under cryogenic machining.

Moisture-Accelerated Precursor Crystallisation in Ambient Air for High-Performance Perovskite Solar Cells toward Mass Production.

Phase-pure crystallised perovskite is considered an excellent precursor for fabricating high-stability perovskite films with minimal defects. However, currently available protocols for synthesising crystallised perovskites must be conducted in an inert atmosphere or in the presence of an organic solvent as the reaction medium, which hinders mass production. Here, we report the fast synthesis of α-phase-crystallised perovskite powder assisted by moisture in ambient air. Moisture can promote the reaction between PbI2 and organic salts and facilitate complete phase transition, as demonstrated in a joint experimental and theoretical study. Perovskite solar cells with a power conversion efficiency of 24.07 % were achieved using phase-pure crystallised perovskite powder as the precursor. This ambient-air-compatible method opens new vistas to reproducible high-quality precursors for large-scale photovoltaic applications.

Moisture‐Accelerated Precursor Crystallisation in Ambient Air for High‐Performance Perovskite Solar Cells toward Mass Production

AbstractPhase‐pure crystallised perovskite is considered an excellent precursor for fabricating high‐stability perovskite films with minimal defects. However, currently available protocols for synthesising crystallised perovskites must be conducted in an inert atmosphere or in the presence of an organic solvent as the reaction medium, which hinders mass production. Here, we report the fast synthesis of α‐phase‐crystallised perovskite powder assisted by moisture in ambient air. Moisture can promote the reaction between PbI2 and organic salts and facilitate complete phase transition, as demonstrated in a joint experimental and theoretical study. Perovskite solar cells with a power conversion efficiency of 24.07 % were achieved using phase‐pure crystallised perovskite powder as the precursor. This ambient‐air‐compatible method opens new vistas to reproducible high‐quality precursors for large‐scale photovoltaic applications.

Experimental investigation on machining characteristics of titanium processed using electrolyte sonicated µ-ECDM system

Micromachining of difficult-to-machine materials is of prime focus nowadays. One such material is Titanium, which has numerous applications in aerospace, chemical, and biomedical industries. The micromachining of Titanium has become the need of the day because of its exhilarating properties. This investigation employs a tailor-made electrolyte sonicated micro-electrochemical discharge machining (ES-µ-ECDM) system to generate microholes in a commercially pure titanium plate with a thickness of 1000 µm. The machining chamber is the ultrasonication unit (36 kHz) with process parameters voltage (V), concentration (wt%), and duty factor (DF) chosen at three levels. The FCC-RSM-based DOE is selected for experimentation to study the machining characteristics like material removal rate, overcut, and circularity. Through holes were achieved at parameters of 80 V, 25 wt%, and 60% DF and 80 V, 30 wt%, and 50% DF. The incorporation of ultrasonication into the system enhanced electrolyte replenishment and evacuation of the debris at the machining vicinity. The assistance technique improved the gas film stabilization around the tool enabling uniform machining. The multi-response optimization is performed using the MOJAYA algorithm to obtain Pareto optimal solutions, and the MADM (R-method) is employed to obtain the optimal parameter. The optimal parameter was found to be 69 V, 30 wt%, and 50% DF, at which the machined microhole was found to have a circularity of 0.9615 with minimal surface defects.

Alternate-Target Layer-By-Layer Pulsed Laser Deposition of Epitaxial BiVO4 Thin Films

Bismuth vanadate (BiVO4) has emerged as one of the highest performing metal oxide photoelectrodes for solar energy-to-fuels applications [1, 2]. This achievement has been largely attributed to the development of high-quality synthesis techniques. Specifically, epitaxial synthetic routes to producing lattice-matched, near single-crystalline quality BiVO4 with minimal extrinsic defects have been essential to understand the fundamental and PEC properties of BiVO4 that are inaccessible by conventional bulk synthesis techniques. In addition, epitaxial synthesis may also be employed as a strategy to further improve the PEC properties of BiVO4 through, for instance, altering the band structure and enhancing the carrier dynamics by strain engineering. Hence, the ability to produce high-quality single-phase epitaxial BiVO4 films is desirable.To date, molecular beam epitaxy (MBE), chemical vapor deposition (CVD), and pulsed laser deposition (PLD) [3] have been used to fabricate epitaxial BiVO4 thin films, with PLD having the advantage of relatively simple experimental setup and material versatility. However, an oft-noted drawback in conventional PLD using single oxide targets is off-stoichiometry in the deposited films; this is especially so for BiVO4 which requires a Bi-rich compound target to achieve a stoichiometric BiVO4 film [4]. This problem is also expected in general for multinary oxides composed of elements with very different ablation properties. To alleviate the limitations of conventional PLD, we employ for the first time alternate-target layer-by-layer PLD as a more elegant approach to produce high quality epitaxial BiVO4 films. Briefly, constituent oxide targets are alternately ablated by an excimer laser (λ= 248 nm) to build the desired film one unit cell thick at a time. Stoichiometry is controlled by the number of shots corresponding to a specified laser fluence for the constituent oxide target.To demonstrate the method, we deposited epitaxial BiVO4 films onto (001)-oriented yttrium-stabilized zirconia (YSZ) using 4N-pure Bi2O3 and V2O5 targets. Films grown are single phase BiVO4 as shown by x-ray diffraction. Out-of-plane diffraction peaks indexed to BiVO4(00l) suggests epitaxy of the film onto the substrate; reciprocal space maps of the asymmetric BiVO4(208) and YSZ(204) peaks further confirm the BiVO4(001) || YSZ(001) epitaxial relationship (top figure). Rocking curves of the BiVO4 (004) peak (FWHM ~ 0.015-0.041) indicate high crystalline perfection of the BiVO4 film, almost approaching that of the YSZ substrate (FWHM ~ 0.010). Thickness dependent-rocking curve studies reveal that BiVO4 films are strained to the substrate for film thicknesses under 22 nm; above this critical thickness, film relaxation ensues. In turn, the resulting optoelectronic properties of the BiVO4 film is dictated by its relaxation state. The optical band gap narrows with film relaxation as observed with spectroscopic ellipsometry. Moreover, steady-state photoluminescence emission spectroscopy reveals a sub-bandgap state (A 2, bottom figure) associated with strained BiVO4 films, on top of a state consistent with band-to-band recombination (B1 ). A higher energy sub-bandgap state (A 1, bottom figure) develops as the film relaxes. The implications of the relaxation state on the charge carrier dynamics and photoelectrochemical properties of BiVO4 will be discussed. Figure: (top) reciprocal space maps of the asymmetric BiVO4(208) and YSZ(204) peaks; (bottom) photoluminescence emission spectra of strained and relaxed BiVO4 films.

On the use of X-ray microtomography to control artificial defect geometries produced by metal additive manufacturing

ABSTRACT In the field of metal additive manufacturing (AM), defect control and monitoring is a crucial issue regarding recent developments for aeronautics and aerospace applications, especially for mechanical performances and quality control. The present work addresses methodologies to build specific geometries of defects using various metal additive manufacturing processes and based-materials. X-ray microtomography is used to validate the methodologies, control the reproducibility and positioning of the defects, and define the minimal achievable defects size. Hot Isostatic Pressing is applied to the samples to close the pores. The final microstructure is then compared to the as-built one. In future work, generated pore geometries will be used as building models to study the impact of pore shape and position on mechanical properties.

Towards High-quality graphite oxide from graphite – Systemization of the balance in oxidative and mechanical forces for yield enhancement

Despite intensive research on graphene, large-scale production of high-quality graphene oxide/graphite oxide (GO) is challenging. The labour-intensive oxidative mechanical exfoliation is frequently found to be the rate-limiting step. In this study, we report ways to improve GO quality and yield by modifying two promising scalable process variants of Hummers method, viz., Kim’s and Tour’s method for GO production. To achieve a desired crystallite size with minimal defects, we report possible adjustments to the exfoliation process by evaluating the oxidation mechanism against GO’s structural integrity. The modifications such as altering the quantity of the oxidant, the duration of ultrasonic-assisted oxidation and the order of washing cycles improved the oxidation efficiency resulting in yield enhancement of defect-free GO. The structure and quality of the synthesized GO were found to depend on the rigorousness of washing cycles and the quantity of oxidant used rather than on the nature of the oxidant alone.

Advanced Polymeric Nanocomposites for Water Treatment Applications: A Holistic Perspective.

Water pollution remains one of the greatest challenges in the modern era, and water treatment strategies have continually been improved to meet the increasing demand for safe water. In the last few decades, tremendous research has been carried out toward developing selective and efficient polymeric adsorbents and membranes. However, developing non-toxic, biocompatible, cost-effective, and efficient polymeric nanocomposites is still being explored. In polymer nanocomposites, nanofillers and/or nanoparticles are dispersed in polymeric matrices such as dendrimer, cellulose, resins, etc., to improve their mechanical, thermophysical, and physicochemical properties. Several techniques can be used to develop polymer nanocomposites, and the most prevalent methods include mixing, melt-mixing, in-situ polymerization, electrospinning, and selective laser sintering techniques. Emerging technologies for polymer nanocomposite development include selective laser sintering and microwave-assisted techniques, proffering solutions to aggregation challenges and other morphological defects. Available and emerging techniques aim to produce efficient, durable, and cost-effective polymer nanocomposites with uniform dispersion and minimal defects. Polymer nanocomposites are utilized as filtering membranes and adsorbents to remove chemical contaminants from aqueous media. This study covers the synthesis and usage of various polymeric nanocomposites in water treatment, as well as the major criteria that influence their performance, and highlights challenges and considerations for future research.

Determination of Casting Parameters for Affirmative Directional Solidification in 750 KW Francis Runner

Entangled by a web-like pattern of rivers and rivulets, Nepal’s energy sector currently is dominated by hydroelectricity which sustains a major portion of the country’s economy. But still, after more than a hundred years of its operation, the sector’s dependence on imports is uncanny. This not only upsizes the project cost but also the time and human resources. The research, therefore, aims to aid the cause by examining the prospect of manufacturing runners using local industrial expertise in synchronization with available data and research. Here, the paper focuses on the sand casting of a 750KW Francis runner and the design of its parameters namely gating and feeding system to ensure directional solidification. Apart from the conventional procedure, the casting of the runner was proceeded as three separate parts: hub, shroud, and blade which were later welded together. The gate and riser placement for each of the parts was designed independently and analysed for any shrinkage porosities and possible voids using computer simulation with several iterations each. Specifically, temperature variations during three major stages of solidification assigned as 0, 50, and 100 were tested for a total of 195 nodes. The design was then transferred into the mould and casting was performed. The procedure resulted in a cast with a clean surface finish and minimal visible defects. The study, thus, suggests the possibility of manufacturing runners through metal casting and its substantial implications in the improvement of the hydropower industry in Nepal.

Surgical Treatment Outcomes of Tetralogy of Fallot: Experience of the Cardiovascular Department of the Mohammed VI University Hospital in Marrakech.

BackgroundTetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. The surgical approach to TOF continues to evolve, with many centers now favoring early repair for TOF. This study aimed to determine the prevalence of postsurgical complications such as pulmonary insufficiency, residual pulmonary stenosis, and interventricular communication.MethodologyWe conducted a cross-sectional, observational study with a descriptive and analytic focus involving 61 patients who were operated on for TOF.ResultsIn total, 39 (63.9%) patients had a regular TOF and 22 (36.1%) had an irregular TOF. In our study, 32 (56.14%) patients had a pulmonary insufficiency, of whom 20 had a minimal pulmonary insufficiency (62.5% of pulmonary insufficiency cases), and 79.4% of patients with right ventricular outflow tract enlargement had pulmonary insufficiency (p < 0.005). Among patients who did not have a right ventricular outflow tract enlargement, three cases of pulmonary insufficiency were identified with a prevalence of 16.6%. Six (10.52%) patients had residual pulmonary stenosis. In addition, two (3.2%) cases of minimal residual ventricular septal defects were identified in this study.ConclusionsPostoperative complications of TOF treatment are frequent and require medical care throughout the lifetime of patients.

Assessing the Importance of Chloroplast and Mitochondrial Small Heat Shock Proteins in Arabidopsis thaliana

Organisms have a dedicated class of proteins to safeguard their proteome – molecular chaperones. Many chaperones help proteins fold and unfold, maintain their structure, and even re‐fold denatured protein aggregates by using ATP. Small heat shock proteins (sHSPs) are ATP‐independent chaperones that are proposed to prevent irreversible aggregation of denaturing proteins and handing them off to the ATP‐dependent chaperones. sHSPs are especially diverse in plants, possibly due to the exposure of plants to environmental stress due to their sessile nature. Despite their widespread occurrence, little is known about the exact function and role of sHSPs, especially in chloroplasts and mitochondria. Both organelles are critical to plant growth, development and reproduction and are also sources of cellular stress via production of reactive oxygen species. Understanding the role of sHSPs in these organelles is vital to grasp how plants deal with stress and could allow for transferring this knowledge into crop plants to improve agricultural yield. The model plant Arabidopsis thaliana possesses four sHSPs localized to the chloroplasts and mitochondria. HSP23.5‐MI/CP and HSP23.6‐MI/CP are thought to dual‐localize to both organelles, HSP25.3‐CP localizes to chloroplasts and HSP26.5‐MII is targeted to mitochondria. These sHSPs are primarily expressed under heat stress conditions. We have developed single, double, triple and quadruple knockout mutants of these four organelle sHSPs and confirmed that they are protein nulls by immunoblotting with specific antisera. Under standard growth conditions these organelle sHSPs appear dispensable, as the knockout mutants grow similarly to wild type. Notably, the organelle sHSP mutant plants show only minimal growth defects when heat stressed, which is in stark contrast to a lethal phenotype shown by a null mutant of the ATP‐dependent chaperone HSP101. Further work is in progress to determine if chaperones or other proteins are altered in expression to compensate for absence of the sHSPs during stress. Additionally, the dual‐localization of HSPs 23.5‐MI/CP and 23.6‐MI/CP has yet to be fully established and also raises the question of crosstalk between chloroplast and mitochondrial sHSPs. To answer these questions a combination of immunoblotting and proteomics approach on isolated chloroplasts and mitochondria is being taken.

Tough and Fatigue Resistant Cellulose Nanocrystal Stitched Ti3 C2 Tx MXene Films.

Ti3 C2 Tx MXene (or "MXene" for simplicity) has gained noteworthy attention for its metal-like electrical conductivity and high electrochemical capacitance-a unique blend of properties attractive toward a wide range of applications such as energy storage, healthcare monitoring, and electromagnetic interference shielding. However, processing MXene architectures using conventional methods often deals with the presence of defects, voids, and isotropic flake arrangements, resulting in a trade-off in properties. Here, a sequential bridging (SB) strategy is reported to fabricate dense, freestanding MXene films of interconnected flakes with minimal defects, significantly enhancing its mechanical properties, specifically tensile strength (≈285MPa) and breaking energy (≈16.1MJm-3 ), while retaining substantial values of electrical conductivity (≈3050Scm-1 ) and electrochemical capacitance (≈920Fcm-3 ). This SB method first involves forming a cellulose nanocrystal-stitched MXene framework, followed by infiltration with structure-densifying calcium cations (Ca2+ ), resulting in tough and fatigue resistant films with anisotropic, evenly spaced, and strongly interconnected flakes - properties essential for developing high-performance energy-storage devices. It is anticipated that the knowledge gained in this work will be extended toward improving the robustness and retaining the electronic properties of 2D nanomaterial-based macroarchitectures.

Multi-functional cyclic ammonium chloride additive for efficient and stable air-processed perovskite solar cells

Because morphology and defect of organic-inorganic halide perovskite film is very sensitive to moisture and oxygen, it is important to develop humidity tolerant air-processes that produce high quality film with minimal defects for the successful commercialization of perovskite solar cells (PeSCs). As an attempt to optimize perovskite film in the air, we develop a cyclic quaternary ammonium chloride (N-(2-hydroxyethyl)-N-methylpyrrolidinium chloride, M-P chloride) with a pentagonal ring and hydroxyl functional group as an effective additive. The Cl− anions in M-P chloride increase the crystallinity and the grain size by retarding nucleation and growth rate. After crystal growth, bulky M-P chloride diffuses out and remains on the grain boundaries and surface of the perovskite, and thus passivates both types of defects. Furthermore, since the M-P chloride may act as a moisture absorber, the intermediate phase of the perovskite can be protected from the moisture. As a result, this strategy can not only modulate the crystallinity and film morphology but also passivate the defects, leading to enhanced efficiency and stability, regardless of humidity. In particular, even at high humidity of ∼77%, PeSC with M-P chloride exhibits 18.20% power conversion efficiency (PCE) without any hysteresis behavior.