Potassium Stearate Research Articles

Structural Features, Physicochemical Properties, and In Vitro Digestibility of the Starch-Lipid Complexes Formed between High Amylose Starch and Stearic Acid or Potassium Stearate.

Starch-lipid complexes were prepared from high amylose starch (HAS) with stearic acid (SA) or potassium stearate (PS) at different molar concentrations. The complexes (HAS-PS) formed between HAS and PS showed polyelectrolyte characteristics with ζ-potential ranging from -22.2 to -32.8 mV, and the electrostatic repulsion between anionic charges restricted the starch chain reassociation and facilitated the formation of V-type crystalline structures upon cooling. The hydrophobic effects enabled recrystallization of the SA, and the HAS-SA complexes exhibited weaker V-type crystalline structures than the HAS-PS complexes; both HAS-SA/PS complexes were of a similar "mass fractal" type, with a dimension varied from 2.15 to 2.96. The HAS-SA complexes had a considerable content of resistant starch (RS, 16.1~29.2%), whereas negligible RS was found in the HAS-PS complexes. The findings from the present study imply that the molecular order of starch chains and the macro-structures of starch particles are more important to regulate the digestibility of starch-lipid complexes than the crystalline structures.

Mitigation of autogenous shrinkage of alkali-activated slag mortar by stearate salts

The autogenous shrinkage of the stearates-modified alkali-activated slag (AAS) mortar was investigated in this study. The experimental results suggested that the maximum reduction (25 %) of autogenous shrinkage of AAS can be achieved by adding 0.5 wt% calcium stearate, while potassium stearate and sodium stearate seem less effective in decreasing shrinkage. According to the results obtained, the mechanisms of shrinkage mitigation are mainly associated with the retardation of hydration, the coarsening of pore structure, and the increased contact angle. It is estimated that the capillary pressure of pores was reduced by 30 % ∼ 60 % when stearates were used. However, the elastic modulus of AAS was reduced by 20 % due to the bubble-stabilizing effect of stearates, especially at higher dosages, which would partially offset its decreasing effects on autogenous shrinkage. It is also found that the traditional physical model could be used to predict the autogenous shrinkage of plain and modified AAS samples, provided the effect of both elastic and creep parts is considered.

Potassium stearate doped PEDOT:PSS improves the performance of inverted perovskite solar cells.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) suffers from lower conductivity and surface defects, which hinders the extraction and transport of effective charges, thereby reducing the Power conversion efficiency (PCE) and long-term stability of PSCs. Therefore, this study introduces potassium stearate (KSt) doping in PEDOT:PSS to regulate its conductivity and interface charge transfer. As a result, KSt-doped PEDOT:PSS increase the PCE of the device from 16.35% to 18.35%. Moreover, the PCE of PSCs with KSt-doped PEDOT:PSS can maintain 87% of its initial value after being stored in a glove box for over 700 hours. This work provides a simple and effective method for designing high-performance and stable PSCs.

Molecular self-assembling structure and formation mechanism of lubricating grease: A computational simulation approach

Grease is an important type of lubricant. In this study, a computational simulation strategy suitable for revealing the self-assembled structure of grease and its formation mechanism is investigated by combining the advantages of quantum mechanics, molecular dynamics, and dissipative particle dynamics. The results show that the main driving force of self-assembly of thickener molecules in oil is electrostatic force; the molecular configuration of the thickener changes from a bending to a stretching state during the cooling process. The simulation methods developed in this work are successfully applied to study the formation mechanism of sodium stearate and potassium stearate grease, and the results are in good agreement with the experimental results.

Sanitary and hygienic characteristics of potassium stearate as a source of anthropogenic pollution of water reservoirs

Monitoring of surface water quality indicates deterio­ration of its quality due to anthropogenic pollution. Among them, potassium stearate (PS) occupies a prominent place. The purpose of the study is to substantiate regulations of potassium stearate in the water of reservoirs on the basis of sanitary and hygienic assessment of potassium stearate, study its stability and transformation, the impact on the organoleptic properties of water, the sanitary condition, self-cleaning processes and the sanitary condition of reservoirs. Research methods – bibliographic, analytical, statistical, sanitary and hygienic. It was found that the average effective concentration of PS by taste for the threshold of sensation (1 point) was at the level of 6.43 mg/dm3. The intensity of the taste of 1-2 points was maintained for 10 days. Potassium stearate is a hydrolyzing and non-chlorinating substance. As a result of assessing the impact of potassium stearate on the processes of self-purification of water from organic pollution by observing the dynamics of water oxidation, dissolved oxygen concentration and biochemical oxygen demand (BOD), the processes of ammonification, nitro- and nitrification, it was found that the limiting potassium stearate for reservoirs is BOD. On the basis of threshold and inactive concentrations by all limiting signs of harmfulness one allows recommending the maximum permissible concentration for potassium stearate at the level of 0.25 mg/dm3. The limiting indicator of harm is sanitary. Comprehensive assessment of the obtained expe­rimental and calculated data by the hygienic rationing of PS in general the water of open reservoirs allows classifing it as the 4th class of danger (practically non-toxic substances).

Lamellar crystalline networks in the gel-like phase of potassium stearate-stearic acid-water

The gel-like phase constructed by fatty acid compounds is a kind of fascinating soft matters but its structural characteristics have not been fully understood. This work has investigated the crystalline structures and formation mechanism of gel-like phase containing potassium stearate (KS), stearic acid (SA), and water at 80% neutralization degree. The crystalline fibers are observed in the gel-like samples of KS-SA-water on the polarized optical microscopy. X-ray diffraction measurement demonstrates that there are two isolate types of lamellar crystallites of KS and KS-SA complexes instead of the mixed crystallites in KS-SA-water samples. While KS crystallites have shorter Bragg spacing and tilted angle than the crystallites of KS-SA complexes, it is found that the solvent of water does not penetrate in the interlayer of two kinds of crystallites. The dynamic rheology measurement suggests the strong elasticity of KS-SA-water samples, which indicates the network structure formed by the lamellar crystalline fibers entrapping water. The addition of glycerol does not affect the crystalline structures of KS-SA-water samples, but significantly increase the values of storage modulus and melting enthalpy. This result suggests that the added glycerol can promote the strength of the hydrogen bonding between the solvent and crystalline fibers in the network structure of KS-SA-water samples. These findings provide new insights to the structural properties of gel-like phase of fatty acid compounds, which are importantly helpful for controlling their structure and functions. • There are two isolate types of lamellar crystallites of KS and KS-SA complexes. • Water and glycerol do not penetrate in the interlayer of lamellar crystallites. • Network structure is formed by the crystalline fibers entrapping the solvent. • Glycerol can promote the hydrogen bonding between the solvent and crystallites.

Impact of lead acetate and sodium and potassium stearates on lipid peroxidation processes in the body of experimental animals

Introduction. Given the significant prevalence of lead in the environment, research in this area has significant social and economic importance. Lead compounds are characterized by high toxicity and increased ability to cumulate in ecosystems, humans, and animals. Lead enters the human body with food, drinking water, atmospheric air, and smoking. Lead causes pathological changes in the nervous system, blood-forming organs, kidneys, etc. Materials and methods. The experiments were carried out on four groups of white female rats, each included seven animals, weighing 150-200 g. The first group of animals was a control. The second group consumed dechlorinated water from the city water supply, followed by lead acetate. The animals from the third and fourth groups drank the same water with sodium stearate and potassium stearate content in a dose of 1/250 LD50. After the 40th-day of the use of these waters, the animals were orally administered lead acetate at a dose of 7 mg/kg. The levels of lipid peroxidation biomarkers were studied by studying the content of diene conjugates (DC) and malondialdehyde (MDA) in blood serum, liver, and kidney homogenates. Results. The administration of 1/2 acetate LD50 to lead in experimental rats drinking water with stearates was accompanied by a significant increase in the DCs concentration and (MDA) in animals. Higher concentrations of LPO products were observed in the group of animals that consumed water from potassium stearate. Conclusions. 1. With the oral administration of lead acetate against the background of drinking water containing stearates at a dose of 1/250 LD50, an increase in lipid peroxidation indices was noted compared with the control group. 2. Higher concentrations of LPO products were observed in the group of animals consuming water from potassium stearate.

Synthesis, Study of Dielectric Properties, Thermogravimetric Analysis and Hemolytic Effect of Copolymers Based on Various Derivatives of Styrene and α-Methylstyrene

The paper describes the synthesis of three new copolymers based on styrene and α-methylstyrene derivatives by radical emulsion copolymerization in an aqueous medium in the presence of an ammonium persulfate initiator and potassium stearate emulsifier. In early study, it was found that copolymers based on methoxy derivatives of styrene have the advanced dielectric properties, as compared to polystyrene and a copolymer of styrene and α-methylstyrene. In addition, the latest scientific literature provides data on the biological activity of styrene copolymers. Thus, the synthesis and study of the properties of new copolymers based on styrene and α-methylstyrene creates a prospect for establishing materials with a unique set of properties differing from their previously studied analogues. The structure of synthesized copolymers is confirmed by IR spectroscopy. Along with this, the paper provides the curves of thermogravimetric analysis, data on dielectric constant and tangent of a dielectric loss angle. A hemolytic effect of copolymers is determined, which indicates biocompatibility and further research perspectives towards their suitability for medical use. A copolymer of sodium 4-styrenesulfonate and α-methylstyrene (the molar ratio of starting monomers is 7:3) is soluble in an aqueous medium, which makes it of higher priority in terms of further study into biological activity.

Синтез новых сополимеров на основе 2,3,4,5,6-пентафторстирола, стирола, α-метилстирола и 4-фтор-α-метилстирола

At the first stages of the research work, a copolymer of styrene and α methyl styrene was synthesized by the method of radical emulsion polymerization in an inert atmosphere of argon. The initiator was ammonium persulfate. The molar ratio of the initial monomers of styrene and α-methylstyrene was 70 : 30, respectively. It was found that copolymers synthesized under special controlled conditions have good values of permittivity and dielectric loss tangent. It should be noted that the choice of emulsifier directly affects the values of these indicators. It was previously shown that the most optimal emulsifier is potassium stearate, using which the best values of the dielectric constant and dielectric loss tangent were achieved. At the second stage of the research work, a number of copolymers were synthesized containing 4-methoxystyrene, 4 methyl styrene and α-methyl styrene in their structure. It was experimentally confirmed that the synthesis procedure may be applicable for the preparation of copolymers based on derivatives of styrene and α-methylstyrene. The resulting series of copolymers is highly soluble in methylene chloride; films of each copolymer sample of different thicknesses were obtained by casting from a solution. For this series of copolymer films, the dielectric constant and dielectric loss tangent were determined. It was found that the best values of permittivity and dielectric loss tangent are possessed by a sample of copolymer 4-methoxystyrene and α-methylstyrene. At the latest stage of the study, copolymers of styrene and 2,3,4,5,6-pentafluorostyrene, α-methylstyrene and 4-fluoro-α-methylstyrene, 2,3,4,5,6-pentafluorostyrene and 4-fluoro-α-methylstyrene were synthesized. These fluorine-containing derivatives of styrene and α-methylstyrene easily enough enter into the reaction of radical emulsion copolymerization. The copolymer yields are 53-76%, calculated on the weight of the starting monomers. The structure of a number of newly synthesized copolymers was confirmed by IR spectroscopy. In the future, it is planned to define the values of dielectric constant and dielectric loss tangent for these copolymer samples. It is planned to study the thermomechanical properties of the samples, since fluorine-containing polymers are a promising material for operation at elevated temperatures.

INFLUENCE OF LEAD ACETATE IN CONJUNCTION WITH STEARATES ON THE BONE BRAIN AND PERIPHERAL BLOOD OF SUSPICIOUS ANIMALS

In modern conditions, industrial pollution of the environment with lead is quite significant and has an adverse effect on the body. It has pronounced cumulative properties and is accumulated in bones in the form of insoluble tri-phosphorus. However, under the influence of certain conditions, its reserves in the bones become mobile; it transits into the bloodstream and can cause poisoning, even in the sharp form.
 The aim – to study the effect of lead acetate in the body at sub-toxic doses on the background of drinking water with stearates content.
 Materials and Methods. To study the influence of low-frequency lead in isolation and in combination with stearates under conditions of a subacute sanitary-toxicological experiment, the animals were divided into four groups of 7 animals each. The group 1 of animals was a control group. The group 2 of animals consumed dechlorinated water from the city water supply (water + AcPb). Animals of the groups 3 and 4 also consumed dechlorinated water from the city water supply, but with an admixture of sodium stearate (group 3 StNa + AcPb) and potassium stearate (group 4 StK + AcPb) at a dose of 1/250 LD50. After a 30-day application of these waters to animals, the groups 2, 3 and 4 were orally administered lead acetate at a dose of 7 mg/100 g of body weight (1/110 LD50).
 Results and Discussion. As a result of the action of lead acetate in a dose of 70 mg/kg and stearates, there was an increase in the bone marrow of the number of promyelocytes, stem cells, segmental neutrophils of lymphocytes and normocytes. However, the number of myelocytes and metamyelocytes decreased. Lead acetate and stearates caused an increase in the number of rodenuclear neutrophils, eosinophils, monocytes, lymphocytes and a decrease in the number of segmental neutrophils in the blood of experimental animals. Unlike intact animals in the groups 2, 3 and 4, there were observed events of functional failure of the erythrocytes system such as anisocytosis, poikilocytosis and hypochromia.
 Conclusions. 1. Thus, with the action of lead acetate at a dose of 70 mg/kg in combination with sodium and potassium stearates, there was an increase in the bone marrow of promyelocytes, stabnoid, segmented neutrophils of lymphocytes and normocytes. The number of myelocytes and metamyelocytes decreased.
 
 Lead acetate in combination with sodium and potassium stearates caused an increase in the number of stab neutrophils, eosinophils, monocytes, lymphocytes and a decrease in the number of segmented neutrophils in the blood of experimental animals.

Formulation and characterization of some oil in water cosmetic emulsions based on collagen hydrolysate and vegetable oils mixtures

Abstract The present study was focused on the preparation and characterization of different topical oil in water emulsions based on natural ingredients such as collagen hydrolysate and vegetable oils mixtures. As oil phases, mixtures of coconut, almond, jojoba, avocado oils (in different ratios) were used while the water phase consisted in lavender water. As emulsifier, a plant based product containing glyceryl stearate and potassium stearate was incorporated (in the concentration range 4–5 %), while as rheology modifier xanthan gum was used (in the concentration range 0.2–1 %). As preservatives, Cosgard (containing benzyl alcohol, salicylic acid, glycerol, ascorbic acid) and mixtures of two essential oils (lemon and lavender) were selected. The designed formulations were assessed by means of their physico-chemical properties (pH, viscosity, thixotropic behavior), optical microscopy analysis and sensorial characteristics. The obtained emulsions were found to present pseudoplastic and thixotropic behaviors, adequate for cosmetic skin care product formulations.

Измерение величины удельного объёмного сопротивления в ряду сополимеров 4-метилстирола–α-метилстирола и 4-метоксистирола–α-метилстирола

In the course of previous experiments, a technique was developed for the preparation of a copolymer of styrene and α-methylstyrene. This technique is an emulsion polymerization in the initiator of ammonium persulfate in an inert zone of direct current argon. It was found that the best emulsifier is potassium stearate. This substance can be explained by those copolymers that showed the best dielectric performance. In the course of the new experiment, a series of new copolymers of 4-methylstyrene-α-methylstyrene and 4-methoxystyrene-α-methyl-styrene was obtained in the molar ratios of the initial monomers of 8 : 3, 9 : 2 and 10 : 1 for both rows of copolymers. The outputs of the pure product for all compounds accounted for more than 60% in terms of the initial monomers. To further measure the value of the specific volume resistance of the material, films of each newly synthesized copolymer were obtained. Samples of the copolymers were dissolved in methylene chloride and applied to a smooth glass substrate. The choice of this solvent is due to its low toxicity and low boiling point. For the experiment were selected samples with a film thickness of 50 microns. Measurements of the specific volume resistance were carried out at the Research Institute "Girikond" (St. Petersburg) using an Agilent 4339B instrument. The operating voltage was 100 V. The measurement results showed that samples of 4-methoxystyrene-α-methylstyrene copolymer were several orders of magnitude superior to samples of 4-methylstyrene-α-methylstyrene copolymer. Most likely in this case such a difference in the indices of the specific volume resistance of the copolymer films is due to the nature of the functional groups of substituents in the copolymer. From the obtained measurement results it can be seen that the samples containing the methoxy group have a high resistance value compared to the samples containing a methyl group in their structure. In a series of samples of copolymer films, an increase in the specific volume resistivity index is observed with a decrease in the α-methylstyrene content in the copolymer structure. This dependence is observed for copolymers of 4-methylstyrene-α-methylstyrene and for 4-methoxystyrene-α-methylstyrene. The sample of 4-methoxystyrene-α-methylstyrene with a molar ratio of initial monomers of 10 : 1 has the highest value of specific volume resistance among all the obtained samples of copolymer films.

Molecular dynamics research on geometric effect of nanostructured diamond-like carbon substrates on potassium stearate adsorption

Molecular dynamics (MD) simulations were performed to investigate the geometric effect of nanostructured substrates on adsorptive behavior of potassium stearate monolayers. A typical protective coating, diamond-like carbon (DLC), was employed as adsorptive substrates. For the substrates with square grooves, complete penetration of molecules can only occur under large width and small depth. The occurrence of partial penetration would make monolayer atoms away from substrate surfaces and therefore induce weak substrate-molecules interactions. Compared with the square groove bottoms, monolayers are much more strongly adsorbed to the groove concave corners. For substrates with triangle and semi-circle grooves, complete penetrations are achieved in both cases and thus monolayer atoms can interact with the whole groove surface. The effect of substrate morphology on monolayer adsorption would be sufficiently weakened by the decrease of geometric size, and the surface adsorptivity of semi-circle grooves with large radius is similar to that of the smooth surface. The results indicate that the substrates with triangle grooves have better adsorptivity than other morphologies.

Вплив питної води з різним вмістом стеаратів калію і натрію на вільнорадикальні процеси в організмі щурів

Introduction One of the reasons for the lack of quality drinking water is the poor quality of natural water, which is constantly polluted by waste water from industrial and municipal enterprises, surface runoff from the fields and territories of settlements with which it enters a large amount of toxic substances. Among them, surface-active substances such as potassium and sodium stearate are not the last.The aim of the study to determine the specifics of lipid peroxidation and the state of the antioxidant protection under the influence of potassium and sodium stearates on the body of the experimental rats when they enter with drinking water.Research Methods. White rats were divided into 7 groups, which consumed water with stearates in quantities equal to the maximum non-active dose of the substance (MND), 1/2 MND and 1/4 MND for 25 days. The content of TBC-active lipid peroxidation products, diene conjugates and the activity of superoxide dismutase and catalase in liver homogenate were determined.Results and Discussion. In the homogenate of the liver of animals of all groups, there was a significant increase in the level of diene conjugates and TBK-active products in proportion to the concentration of the substance. It was also found that in animals that consumed water with different concentrations of potassium stearate, inhibition of antioxidant enzymes was observed. Consumption of water with different concentrations of sodium stearate caused the activation of these enzymes.Conclusions. Prolonged use by test animals of aqueous solution with concentrations of potassium and sodium stearate in MND and 1/2 MND negatively affects the state of hepatocyte cell membranes due to the activation of the lipid peroxidation processes, namely TBK-active products and diene conjugates, the amount of which depended on the concentration of stearates in drinking water. The use of drinking water by test animals with maintenance of potassium and sodium stearates at various doses caused changes in the content of antioxidant enzymes: water with potassium stearate inhibits the activity of these indicators, and causes sodium activation with sodium stearate.

Influence of surface morphology on adsorption of potassium stearate molecules on diamond-like carbon substrate: A molecular dynamics study

Molecular dynamics (MD) simulations were used to provide insights into the influence of nano-scale surface morphology on adsorptive behavior of Potassium stearate molecules on diamond-like carbon (DLC) substrates. Particular focus was given to explain that how the distinctive geometric properties of different surface morphologies affect the equilibrium structures and substrate-molecules interactions of monolayers, which was achieved through adsorptive analysis methods including adsorptive process, density profile, density distribution and surface potential energy. Analysis on surface potential energy demonstrated that the adsorptivity of amorphous smooth substrate is uniformly distributed over the surface, while DLC substrates with different surface morphologies appear to be more potentially corrugated, which improves the adsorptivity significantly. Because of the large distance of molecules from carbon atoms located at the square groove bottom, substrate-molecules interactions vanish significantly, and thus potassium stearate molecules cannot penetrate completely into the square groove. It can be observed that the equilibrium substrate-molecules interactions of triangle groove and semi-circle groove are much more powerful than that of square groove due to geometrically advantageous properties. These findings provided key information of optimally design of solid substrates with controllable adsorptivity.

Wettability and Corrosion Behavior of Chemically Modified Plasma Electrolytic Oxidation Nanocomposite Coating

The aim of this paper was to investigate the effect of potassium stearate on the wettability behavior, corrosion resistance, roughness and thickness of reinforced and unreinforced plasma electrolytic oxidation (PEO) coatings with Si3N4 nanopowders. Morphological characteristic, corrosion behavior and wetting properties of the coatings were evaluated using SEM, cyclic polarization and Wilhelmy plate method, respectively. In order to obtain a better evaluation of the contact angle, roughness of the coatings was studied by AFM. The results indicated that the nanocomposite hydrophobic coatings have the best corrosion resistance. Potassium stearate could repel water from the holes of coating by reacting with aluminum and producing aluminum stearate. The contact angle of nanocomposite and normal PEO coatings was increased up to 65° due to the addition of potassium stearate. This additive could also increase the hysteresis contact angle up to 51°.

An investigation of the adsorption of potassium stearate molecules on diamond-like carbon substrate using molecular dynamics simulation

Molecular dynamics (MD) simulations were performed to investigate the adsorption of potassium stearate molecules on diamond-like carbon (DLC) substrate. The effects of non-bonded interactions and confinement conditions on the adsorption were investigated. The confinement conditions performed herein were achieved by imposing a Z-direction constraint on the movement of molecules in the initial stage of adsorption, and then releasing the molecules from the constraint gradually. Our simulation results show that the polar end groups of molecules tended to accumulate during the adsorption, and the final distribution of adsorptive film without confinement was irregular. Under confinement conditions, the adsorptive film was evenly distributed on the substrate after reaching its equilibrium configuration, and the final inter-subsystem potential of the substrate on adsorptive film was obviously decreased as compared with the results without confinement. These findings provided an effective approach for promoting the adsorption of molecules.

Corrosion and wettability of PEO coatings on magnesium by addition of potassium stearate

Abstract Hydrophobic PEO coatings were fabricated in an electrolyte containing potassium stearate. The wetting behaviour of coated samples was studied using dynamic and static contact angle. Also, the corrosion behaviour of the samples was evaluated by polarization method. The dynamic contact angle and hysteresis of the contact angle for PEO coating were evaluated by Wilhelmy plate method. There was an increase in the contact angle of the nanocomposite and traditional PEO coatings when potassium stearate was added to the electrolyte up to 130°. The more hydrophobic coatings, showed more corrosion resistance in 3.5 wt.% NaCl solution. The synergistic effect of potassium stearate and nanoparticles increased the hydrophobicity because of assembling of fatty acid on ceramic powder.

Features of free oxidation in liver homogenates of rats in combined action of copper and subtoxic level of stearate potassium and sodium

Toxic effects of heavy metals on animals and humans is aggravating the presence of surfactants. The aim of our research was to identify the peculiarities of free radical oxidation and antioxidant protection in the use of drinking water with subtoxic doses of potassium and sodium stearates in combination with copper on the body of warmblooded animals, such as the liver of experimental rats. Analysis of indicators allows asserting that in experimental rats liver homogenate observed activation of free radical oxidation, the intensity of which depended on the concentration of stearates in water. More pronounced changes were in animals that consumed water with potassium stearate.The action of potassium stearate observed inhibition of antioxidant systems while under the influence of sodium stearate – its activation. Changes in performance were more pronounced in combination stearates with copper.

Inverted polymer solar cells with enhanced fill factor by inserting the potassium stearate interfacial modification layer

A thin potassium stearate (KSt) film combined with an optimized ZnO film was introduced to improve the fill factor (FF) of highly efficient inverted polymer solar cells (PSCs). Atomic force microscopy and contact angle measurements were used to show that the introduction of KSt did not change the morphology of interlayer. On the contrary, it is beneficial for the spread of the active layer on the interlayer. The origin of enhanced FF was systematically studied by the ideal current-voltage model for a single heterojunction solar cell and electrochemical impedance spectroscopy. On the basis of the data analysis, the reduced charge recombination loss was responsible for this improved FF. At last, when KSt was replaced by sodium stearate (NaSt), the similar experiment phenomenon was observed. This indicates that inserting a metallic stearate modified layer is a promising strategy to enhance inverted PSCs performance.