Dark Ambient Conditions Research Articles

Heterogeneous Nucleation and Enhanced Charge Transfer via Amorphous Metal‐Organic Frameworks for Efficient and Stable Perovskite Solar Cells

AbstractThe two‐step sequential deposition method is considered a potential way for the large‐scale manufacture of perovskite solar cells (PSCs) with high power conversion efficiency and reproducibility. However, the dense lead iodide (PbI2) film interferes with its full contact with organic solutions, resulting in an inadequate reaction at the interface. Herein, 2 kinds of metal‐organic framework (MOF) are introduced, amorphous Ni‐MOF‐74 (amNi‐MOF‐74) and crystalline Zn‐MOF‐74 (crZn‐MOF‐74), into PbI2 for regulating crystallization. Compared to crZn‐MOF‐74, the incorporation of amNi‐MOF‐74 exhibited rapid nucleation, resulting in high‐quality perovskite films with large grain size, low trap density, and enhanced charge transfer between the perovskite and charge transfer layers. Meanwhile, the content of unstable phase PbI2 left in perovskite films due to insufficient reaction is also reduced. The amNi‐MOF‐74 modified PSCs exhibited a champion power conversion efficiency of 24.17% with good humidity and thermal stability. The unencapsulated device maintains 90% of its initial efficiency after 1000 h storage in dark ambient conditions with ≈30% relative humidity. This strategy provides an effective approach for promoting the crystallization process of perovskite and fabricating efficient and stable PSCs.

SnS thin films deposited at room temperature – Efficient and reusable dark catalyst for water remediation at ambient conditions

This study describes the dark catalytic degradation of cationic, anionic, and commercial dyes by SnS thin films under dark ambient conditions without the assistance of any external stimuli. The thin films were deposited by a modified SILAR (Successive Ionic Layer Adsorption and Reaction) method at room temperature and characterised using XRD, XPS, FESEM, TGA, and UV–visible spectrophotometers. The dark catalytic degradation of methylene blue (MB) dye was investigated using a spectrophotometer and validated by LCMS analysis and an adsorption desorption test. Within 15 min, 48 % of the MB dye (original concentration: 10 mg/l) had been degraded by the catalyst, and by 90 min, the degeneration was almost complete. The ROS (reactive oxygen species) scavenger test and indicator test confirmed the role of the hydroxyl radical in the degradation process. The influence of initial dye concentration, magnetic stirring, and the composition of the catalyst on the degradation efficiency was also studied. The same catalyst was used five times in succession to test its reusability, and it was then structurally and thermally characterised to test its stability. This study emphasises the possible use of SnS thin film as an effective, reliable, and reusable around-the-clock catalyst for the degradation of dye-contaminated waste water without the assistance of light or any chemical additives.

A new azine-based ferrocenophane for azo dyes degradation in dark–ambient conditions

In a novel approach, 1,1′-bis(2,3-diazabuta-l,3‑dien)ferrocenophane (Fc-azine) synthesized by self-condensation of 1,1′-Ferrocenedicarboxaldehyde hydrazone (FcDH) with the aid of Zn(OAc)2·2H2O or acetic acid at 120 °C under high pressure. Fc-azine as an insoluble compound was fully characterized by Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller analyses (BET), powder x-ray diffraction (XRD) and single crystal x-ray diffraction. The narrow band gap (Eg = 1.93 eV) and the presence of ferrocene and azine functional groups encouraged us to use Fc-azine as an advanced oxidation process (AOP) catalyst. Interestingly, the addition of Fc-azine (1 g L-1) to aqueous solutions of 50 ppm of Congo red (CR) and 10 ppm of methyl orange (MO) led to the fast degradation of CR (over 80 % in 5 min) and the slow degradation of MO (98 % in 48 h) in the dark, without additional energy sources or chemical reagents. It was found that Fc-azine can degrade CR in six cycles with high efficiency (over 80 %). CR degradation by Fc-azine can be performed in acid and basic environments (pH= 3–9), and effective MO degradation happens in slightly acidic and natural environments (pH= 5–7). Possible adsorption, reactive oxygen species production (·OH, O2·−), and the mechanism of CR and MO degradation were also studied.

The effect of mediating plant extract on the photocatalytic activity of different eco-friendly synthesized magnetite nanoparticles against cresol red photodegradation

This study investigates the effect of mediating plant extract on the photocatalytic activities of four eco-friendly synthesized magnetite (Fe3O4) nanoparticles (NPs) against the photodegradation of cresol red (CR). For this purpose, the adsorption of CR has been carried out in dark ambient conditions at first to eliminate the impact of adsorption, followed by the recovery of Fe3O4 NPs by a centrifuge. Second, photocatalytic reactions of CR have been conducted on recovered magnetite NPs, under UV-Vis irradiation (365 nm) in ambient conditions. This study presents a novel investigation of the effect of mediating plant extract on the densities of surfacic photoactivated Brönsted and Lewis acid sites on Fe3O4 NPs against photocatalytic reactions of CR. To do so, free auxochromes and chromophores that are not reacted with photoactivated Brönsted and Lewis acid sites have been analyzed using FTIR spectroscopy. This analysis provides insights into the densities of photoactivated Brönsted and Lewis acid sites during CR photodegradation reactions on the four Fe3O4 surfaces and permits their comparison. Found results showed that, during CR photodegradation, the band gap energy is not the single parameter responsible herein for the photoactivation of acid sites and hence photocatalytic activity, but also mediating plant extract plays a crucial role. Where, a decrease in plant extract’s acidity guides to more photoactivate Lewis acid sites, and an increase in the acidity guides to more photoactivate Brönsted acid sites. Because most functional groups of CR are auxochromes that favor reacting with photoactivated Lewis acid sites, the Fe3O4 synthesized using less acidic plant extract showed the highest photocatalytic activity. These results are in accord with the calculated photodegradation capacities, yields, and kinetic rates.

Brownmillerite Calcium Ferrite, a Promising Perovskite-Related Material in the Degradation of a Tight Dye under Ambient Conditions.

Evaluation of effective and low-cost materials as catalysts to combat the threat of pollution is a significant and growing trend. With this aim, we have synthesized calcium ferrite brownmillerite by wet preparation approach as a catalyst for pollution. The structural analysis is established by the X-ray diffraction of Ca2 Fe2 O5 , whereas the tetrahedral and octahedral sites band stretching for ferrite specimen has been deduced using FTIR. The bandgap energy has been estimated by the Tauc relation (2.17 eV). Ca2 Fe2 O5 brownmillerite exhibits a BET surface area of 10 m2 /g and a BJH pore volume of 0.121 cm3 /g with the average particle size of 70 nm. Importantly, the alizarin Red S dye degradation has been studied using the prepared ferrite catalyst, under dark ambient conditions and without the presence of any acidic or basic additives. Degradation is also supported by both FTIR and TOC analysis. Surface properties of brownmillerite Ca2 Fe2 O5 have been characterized using electronic spectroscopy and CO2 temperature programmed desorption (TPD) analysis and revealed that the basic surface of brownmillerite Ca2 Fe2 O5 offers active sites that are suitable for degradation processes. All results show that the preparation of brownmillerite Ca2 Fe2 O5 via the Pechini method is suitable to produce fine surfaces and pores with nanosized particles.

A novel aspect on different preservation methods for tomato paste by examining the protective effect of herb and spice oils.

In this study, the effect of essential oils of herbs and spices on the protection of homemade tomato paste without additives was investigated. Garlic oil was used as plant essential oil and thyme oil was used as spice essential oil. Samples were kept without adding essential oils at the specified holding times in determined light and dark ambient conditions. After the test period of the prepared setups was completed, the amount of mold formed in the tomato paste was observed, and the optimum samples were determined as K4A4, K4K7, K4K13, K6K10, S6K4, S6K7, S6K10, S6A13 by weighing again and creating a %-time graph by mass. It was decided that thyme essential oil had a more protective effect in foods than garlic essential oil, with the analysis methods performed on optimum samples (Physical analysis, microbiological analysis, FT-IR, and TG DTA).

Multifunctional Metal-organic Frameworks Capsules Modulate Reactivity of Lead Iodide toward Efficient Perovskite Solar Cells with Ultraviolet Resistance.

The two-step sequential deposition process is demonstrated as a reliable technology for the fabrication of efficient perovskite solar cells (PVSCs). However, the complete conversion of dense PbI2 to perovskite in planar PVSCs is tough without mesoporous titanium dioxide as support. Herein, multifunctional capsules consisting of zeolitic imidazolate framework-8 (ZIF-8) encapsulant and formamidinium iodide (FAI) are introduced between tin oxide (SnO2 ) and lead iodide (PbI2 ) layer. Intriguingly, the capsule dopant interlayer benefits the formation of porous PbI2 film due to the porous nanostructure of ZIF-8 which is favorable for the subsequent intercalation reaction. Furthermore, the constituent of the perovskite precursor in ZIF-8 pores can convert into the crystal nuclei of perovskite by reacting with PbI2 first, thereby promoting further perovskite crystallization. Significantly, the incorporation of ZIF-8 can enhance the resistance of perovskite against ultraviolet (UV) illumination due to down-conversion effect. Consequently, the modified device achieves a champion power conversion efficiency (PCE) of 24.08% and displays enhanced UV stability, which can sustain 83% of its original PCE under 365nm UV illumination for 300h. Moreover, the unencapsulated device maintains 90% of initial PCE after 1500h storage in dark ambient conditions with a relative humidity range of 50∼70%. This article is protected by copyright. All rights reserved.

Degradation of organic pollutants in the presence of new Mn (II) complexes under ambient light or darkness conditions

The Mn (II) complexes prepared from Schiff’s bases, like salophen type ligands, were complexed via N & O donors under the solvothermal method. These Mn (II) complexes were first validated through elemental data, which was confirmed by mass spectra. At the same time, several spectroscopic practices such as XPS, p-XRD, FT-IR, Raman, FESEM and thermal-stability of the Mn2+ complexes were examined from TGA. The bandgap energies and oxidation potentials of the Mn (II) complexes are assessed with UV–visible DRS and CV investigations. Emission spectra clearly stated that the rate of recombination electron and hole pair is lower for the M−2 complex as compared to the M−1complex. The prepared Mn (II) complexes were used for the mineralization of cationic and anionic dyes such as rhodamine 6G (Rh6G λmax. = 553 nm), and congo red (CR λmax. = 498 nm) under dark ambient conditions. The M−2 complex is more active than M−1 due to its low bandgap energy, low rate of recombination hole-electron pair, and insitu formation of superoxide radicals during catalytic dark ambient mineralization. Active species are identified by ESR studies, which are supported by scavenger data, and then the mechanism of the rapid mineralization of organic dye contaminants is established.

Binary hole transport layer enables stable perovskite solar cells with PCE exceeding 24%

Hygroscopic dopant in hole transport layer (HTL) is a key factor contributing to moisture-induced perovskite degradation and the resulting performance loss over time. This poses obstacles to the commercialization of perovskite solar cells (PSCs). Herein, we mixed two popular hole transport materials, i.e., [2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl-amine)9,9′-spirobifluorene] (Spiro-OMeTAD) and poly (3-hexylthiophene-2,5-diyl) (P3HT), to form a binary mixed HTL. Due to the presence of hydrophobic P3HT component, the mixed HTL exhibits improved moisture resistance. In addition, P3HT demonstrates a great ability to interact with the dopants, which changes π-π packing orientation of P3HT from edge-on to face-on and improves its crystallinity, thus increasing hole mobility and hole extraction capability of the mixed HTL. As a result, PSCs equipped with the Spiro-OMeTAD/P3HT mixed HTL exhibit a champion power conversion efficiency (PCE) up to 24.3% and superior operational stability. The cells without encapsulation can maintain 90% initial efficiency after storage in dark ambient conditions (30% RH) for 1200 ​h. These results suggest that constructing Spiro-OMeTAD/P3HT mixed HTL is a promising strategy to meet the future photovoltaic applications demands with low-cost as well as excellent efficiency and device stability.

Light‐Responsive Polyblend Films with Reconfigurable Surface Micropatterns as Rewritable Information Storage Media

Comprehensive SummaryStimulus‐sensitive surfaces with tunable morphologies exhibit a wide range of applications in the fields of surface science and engineering. Herein, a cost‐effective yet practical strategy is proposed to fabricate photo‐sensitive patterning surface on film/substrate wrinkle system based on an azo‐containing polyblend. By manipulating the stress field of the bilayer system globally and/or locally upon the stress relaxation triggered by the reversible cis‐trans isomerization of the azobenzene, heating/cooling triggered surface wrinkles on the polyblend films could be tailor‐made with visible‐light‐irradiation. Notably, upon selective photo‐irradiation, bespoke surface patterns may be cyclically generated or eliminated, allowing these reconfigurable patterned polyblend surfaces to be used as rewritable information storage media for non‐ink printing. The as‐prepared photo‐printed information patterns with high‐resolution are shown to be rewritable for multiple cycles and legible for over 90 d in dark ambient conditions. This study not only provides a versatile strategy for flourishing the stimulus‐sensitive systems, but also sheds light on the stress relaxation‐triggered morphological evolution of the wrinkling polyblend films.

Biomimetic Synthesis of Highly Reusable MoO3-based Catalysts for Fast Degradation of Dyes

Over the recent decades, unrelenting efforts are being devoted to the sustainable design and synthesis of transitional metal oxide-based photocatalysts with controlled morphology and structural complexity to enhance their catalytic properties. In this account, we have reported the bio-fuel-assisted hydrothermal synthesis of MoO3, MoO3:NiO, and MoO3:PdO/Pd as catalysts to remove azo pollutants from an aqueous solution. Methyl orange was selected as the model dye to represent organic pollutants. This work presents a facile method for improving the visible-light-driven catalytic activity of MoO3 by introducing NiO and PdO. When MoO3:NiO and MoO3:PdO/Pd were illuminated by solar light, emitted radiation originating from oxygen vacancies of NiO and PdO synergistically participated in catalytic reactions of MoO3 giving 98% and 95 % degradation of methyl orange, respectively, in 15 min. To confirm the supporting role of NiO and PdO in the catalysis of MoO3, catalytic experiments were carried out in dark ambient conditions, with only catalysts (without stimulants). Subsequently, the degradation efficiency of MoO3:PdO, and MoO3:NiO was increased to 73% and 84% respectively, from 62 % efficiency of MoO3 suggesting that NiO and PdO greatly increased the efficiency of MoO3 in dark conditions and nearly complete removal of methyl orange by photo-induced visible light degradation. Furthermore, the photocatalysts illustrated good reusability till four runs of experiments without loss in its degradation efficiency. Therefore, the overall catalytic results of the current study are highly proposing MoO3:PdO and MoO3:NiO as excellent photocatalysts for water remediation.

Electrical hysteresis characteristics in photogenerated currents on laser-beam-derived in-plane lateral 1D MoS2-Schottky junctions

Atomically thin two-dimensional transition-metal dichalcogenide materials with van der Waals integration provide various interesting optoelectronic characteristics that can be used to realize highly efficient flexible solar cells and photosensors. We previously reported in-plane lateral one-dimensional Schottky junctions (SJs) on few-atom-layer 2H-phase semiconductor-molybdenum disulfide by forming a 1T′-metal phase using laser beam (LB) irradiation and clarified their unique optoelectronic properties. Although the LB-derived 1T′/2H phase SJs provided efficient photocurrent generation, they had a large number of defects owing to the excess heat accumulation caused by the LB. Here, we observe partial electric hysteresis properties in photogenerated currents (Iphoto) on the SJs under reverse bias voltage regions and reveal that they are very sensitive to the voltage sweep direction and its switching (holding) time. The properties persist under dark ambient conditions for a few minutes, even after photo-irradiation is complete. The temperature dependence reveals that a defect-derived deep carrier trap-center, which is unique to the present 1T′ phase, can be the cause of these phenomena. A larger Iphoto and an increase in photogeneration efficiency are obtained by eliminating this trap center through thermal annealing. In contrast, it is expected that these hysteresis properties lead to atomically thin photo-memristor devices for opto-neuromorphic systems.

Antifouling catalytic mixed-matrix membranes based on polyethersulfone and composition-optimized Zn-Cu-Fe-O CWAO catalyst under dark ambient conditions

ABSTRACT Besides photocatalysts, novel catalytic wet-air oxidation (CWAO) catalysts capable of operating under mild conditions are a potential candidate to fabricate antifouling filtration membranes. This study optimized the CWAO catalyst consisting of three metal oxide components (ZnO, CuO, and Fe3O4) and used it to fabricate composite membranes with PES (polyethersulfone). The catalyst was characterized by methods such as FTIR, BET, XRD, UV-Vis DRS, XPS, ESR. The activity of the catalyst and the composite membranes was tested by the Acid Yellow 42 (AY42) degradation experiments in both cases with and without hydrogen peroxide at room conditions with air aeration. The pure water fluxes of composite membranes were also investigated based on a vacuum filtration system. The major degradation pathways of AY42 by the catalyst were proposed from the DFT (Density Functional Theory) and NBO (Natural Bond Orbital) calculations. The results showed that the optimal catalyst has molar ratios of Zn, Cu, and Fe metal ions of 0.05, 0.588, and 0.362, respectively, with AY42 decomposition efficiency of 88% in 3 h. The main factors affecting the catalytic efficiency of the CWAO catalyst determined from the trapping experiment were e– and O2. The results from different materials characterization methods have demonstrated the successful synthesis of the catalyst with a high surface area (103.5 m2/g) and small pore diameters (∼10 nm). The AY42 degradation of composite membranes was stable over five repeated cycles with over 70% efficiency. The pure water fluxes of composite membranes have also been significantly improved and are proportional to catalyst contents.

Application of OXITEST for Prediction of Shelf-Lives of Selected Cold-Pressed Oils

Introduction: Due to the enhanced awareness of consumers concerning healthy foods, homemade expeller-pressed oils have become popular worldwide. However, an extended storage period may lead to oxidization of the oil and exposure to hazardous byproducts by consumers.Methods: In this study, 10 pressed oil samples prepared from common oilseeds using a small-scale expeller oil press were analyzed by OXITEST with a sample amount of 5 g of oil and an oxygen pressure of 800 kPa under accelerated conditions for shelf-life projections. The oil properties were investigated, including the recovery, smoke point, acid value, iodine value, “fatty acid composition, and contents of pigments and tocopherols”.Results: The autoxidation reaction of various expeller-pressed oils under an accelerated testing system followed zero-order Arrhenius kinetics (R2 > 0.99). Shelf-lives of the pressed oils at 25°C were estimated by extrapolation to range 105~1,089 days. The obtained shelf-lives were significantly correlated with log induction period (IP) values (r > 0.81, p < 0.05) and unsaturated fatty acids (UFAs) (r < −0.69, p < 0.05), but not with the iodine value, acid value, or smoke point. Scatter diagrams between shelf-lives and UFAs suggested that these pressed oils could be grouped by two linear regression curves (r > 0.98, p < 0.05). The predictive equations using multiple linear regression are presented herein, with predictor variables of UFAs and an unspecified item involving potential influencing factors such as tocopherol contents (r > 0.88, p < 0.05).Conclusions: Our findings first revealed that the UFA portion was partially correlated with the shelf-lives of selected expeller-pressed seed oils as estimated by the OXITEST. The derived equations can be applied for shelf-life predictions of expeller-pressed oils stored under dark ambient conditions based on the fatty acid profile.

Optically triggered multilevel resistive switching characteristics of Cu/MoS2/AlN/ITO bilayer memory structure

In this work, the tunable resistive switching (RS) functionality of a Cu/MoS2/AlN/ITO nanostructured device is systematically investigated in dark and white light illumination. The device exhibits bi-state RS behavior in the dark ambient, whereas light illumination induces an extra intermediate resistance state and provides controllable tri-state RS characteristics. A conceptual model is proposed and discussed to elucidate the origin of the switching behavior of two resistance states and multiple resistance states of the device. Under the dark ambient condition, the high resistance state and the low resistance state in the device could be ascribed to the formation/rupture of a Cu metallic filamentary path between the electrodes. However, the formation of an additional ionic filament via trapping/detrapping of electrons in nitride-sulfide-related vacancies along with the Cu metallic filament is responsible for the tri-state switching under the light illumination. Interestingly, the variation of SET voltage with applied light intensity has also been demonstrated. The calculated value of the temperature coefficient and temperature dependency of resistance in various resistance states confirms the existence of the proposed model. The device performed a good undispersed endurance up to 1.5 × 103 cycles and stable retention over 103 s at room temperature. This optical activity dependent functionality of the device provides a possibility to extend resistive switching-based nonvolatile random access memory applications to the optical domain such as imaging sensors, photodetectors, and optoelectronic switches.

Evaluation of ambient light and moisture, and edible coatings in different storage period, on pressurized kiwifruit antioxidant properties

This study aimed to investigate the effect of different storage conditions after a quasi-static load on the amount of some qualitative properties of kiwifruit, including antioxidants, phenol, soluble solid, pH, and hardness. After applying the load, three different coatings were applied to the samples, including grape, dates, and berries juice solution. Then kiwifruit samples were stored for 5, 10, and 15 days. The storage conditions included 90% and 95% humidity, the lighting conditions were completely dark and light with the use of energy-saving lamps. After completion of the storage period, the qualitative properties of kiwifruit samples including antioxidants, phenols, soluble solids, pH, and hardness were measured. The results of the experiments showed that the highest and lowest phenolic content in grape cover and storage period was 10 days with 99.33 mg/100 g and in berry cover and storage period was 15 days with 85.34 mg/100 g. The highest pH was observed in berry cover and storage period of 15 days with 3.49. Also, the lowest pH in grape cover and storage period was 10 days with a value of 2.79. In the stiffness study of the samples, the highest stiffness was observed in grape cover and storage period of 10 days with 15.008 N. In general, the placement of samples in a dark environment could have a beneficial effect on the amount of phenolic content of the samples. Examining the percentage of antioxidants and phenolic content of the samples, the date juice cover, the amount of soluble solids, and the hardness of the grape juice cover and the pH of the berry juice cover were higher than the rest of the factor levels. Increasing the storage period also reduced the amount of antioxidants and increased the amount of soluble solids in kiwifruit samples. Finally, dark ambient light conditions, 5–10 days storage time and grape cover for storing kiwi fruit were the best results.

Degradation efficiency of methyl orange dye by La0.5Sr0.5CoO3 perovskite oxide under dark and UV irradiated conditions

Perovskite oxides have attracted much attention to oxidize and remove effectively several organic pollutants from wastewater. In this work, we report a perovskite oxide La0.5Sr0.5CoO3 (LSCO) for the degradation of methyl orange (MO), a frequently used textile dye, under dark and UV irradiation condition. The LSCO powder was synthesized via the Pechini method and characterized by several techniques. The obtained LSCO presented a rhombohedral phase with a R3‾C space group symmetry. LSCO exhibited a strong photoabsorption property with a bandgap energy of 1.6 eV. The catalytic activity of the LSCO powder was evaluated at different pH values under dark ambient conditions and the result exhibited a higher catalytic activity in the acidic conditions. The MO dye exhibited a degradation rate of 90% in 20 min under both dark ambient and UV irradiation conditions at pH 2.5. The fast degradation kinetics of MO using LSCO in dark was attributed to the double electron generation pathways. The kinetics and reusability of the catalyst were investigated. The MO degradation kinetics under UV irradiation was comparable to the dark condition and it may be due to the optical property of LSCO in the visible region. The results indicated that the LSCO present a good reusability, high catalytic and photocatalytic efficiency and could be used for applications such as wastewater treatment especially in the textile industry.

Bio Framework-Derived Facile MoO3-NiO-PdO-Pd Nanomaterial for Detoxification of Organic Pollutants.

IntroductionThe catalytic behavior of metal oxide nanomaterials for removal of organic pollutants under dark ambient conditions, without any additional stimulant, is of great interest among the scientific community.MethodsIn this account, a nanomaterial of ternary metal oxides (MoO3-NiO-PdO-Pd) was synthesized via greener approach and was explored for degradation of methyl orange in water environment in dark ambient conditions in comparison with light conditions. The biochemical species of Abies pindrow were treated with aqueous solution of precursor’s salt following sol gel synthesis strategy. We further attuned morphology and chemistry of MoO3-NiO-PdO-Pd by incorporating bioactive compounds of A. pindrow.Result and DiscussionThe bio-fabricated MoO3-NiO-PdO-Pd revealed outstanding catalytic behavior with 92% degradation of methyl orange within 15 min in the dark at ambient temperature and pressure. Whereas, in the presence of visible light irritation, the catalyst degraded 97% of methyl orange in 15 min. According to the reaction kinetics of degradation, the catalysts illustrated good stability in light (R2=0.93) as well as in dark conditions (R2=0.98). Furthermore, the outstanding reusability and recyclability of the synthesized nanomaterial was observed for four runs of the experiment under dark and light conditions.ConclusionTherefore, A. pindrow-synthesized MoO3-NiO-PdO-Pd nanocatalyst demonstrated significant potential for detoxification of organic pollutants for water remediation.

Influence of Display Luminance on Visual Discomfort in Dark Ambient Based on Haemodynamic Response

Display luminance is one of the most important factors that influence not only display performance but also visual discomfort greatly. To investigate the influence of display luminance and image content on visual discomfort, the haemodynamic response and subjective perception were recorded respectively when participants watched different visual stimuli. Different white levels (WLs) of display and images with different spatial amplitude spectra were adopted as the visual stimuli, and specific dark environment was applied in the study. The results showed that under dark ambient condition, the WL had significant influences on visual discomfort, which varied in images with different spatial amplitude spectra. The findings also indicated that, for visual discomfort measurement, the sensitivity of haemodynamic response was better than subjective evaluation.

Long-lasting photoluminescence quantum yield of cesium lead halide perovskite-type quantum dots

Cesium lead halide perovskite (CsPbX3, X= Cl, Br, I) quantum dots (QDs) and their partly Mn2+-substituted QDs (CsPb1−xMnxX3) attract considerable attention owing to their unique photoluminescence (PL) efficiencies. The two types of QDs, having different PL decay dynamics, needed to be further investigated in a form of aggregates to understand their solid-state-induced exciton dynamics in conjunction with their behaviors upon degradation to achieve practical applications of those promising QDs. However, thus far, these QDs have not been sufficiently investigated to obtain deep insights related to the long-term stability of their PL properties as aggregated solid-states. Therefore, in this study, we comparatively examined CsPbX3- and CsPb1−xMnxX3-type QDs stocked for >50 d under dark ambient conditions by using excitation wavelength-dependent PL quantum yield and time-resolved PL spectroscopy. These investigations were performed with powder samples in addition to solutions to determine the influence of the inter-QD interaction of the aged QD aggregates on their radiative decays. It turns out that the Mn2+-substituted QDs exhibited long-lasting PL quantum efficiencies, while the unsubstituted CsPbX3-type QDs exhibited a drastic reduction of their PL efficiencies. And the obtained PL traces were clearly sensitive to the sample status. This is discussed with the possible interaction depending on the size and distance of the QD aggregates.