Dispersion Conditions Research Articles

Effects of a chemical dispersant on the dispersibility of Moso bamboo phytoliths in a particle-size analysis

ABSTRACT Phytoliths produced by higher plants are biogenic minerals with a wide range of particle sizes that correspond to clay, silt, and sand in mineral soil. Phytoliths supplied to soils through plants’ death function as soil particles and affect soil physicochemical properties. Investigations of the functions of phytolith particles as a subset of soil particles are facilitated by fractionation and quantification of the phytoliths based on soil particle-size distribution. Fractionation is typically conducted through particle-size analysis (PSA) methods developed for soil texture analyses. However, the effects of chemicals used to achieve particle dispersion in these methods on phytolith dispersibility remain poorly understood. The objective of this study was to examine the effects of chemical dispersants on phytolith dispersibility. Based on the results, several recommendations are provided with respect to the dispersal conditions. The phytoliths used in this study were extracted from Moso bamboo leaf litter through wet digestion and dispersed by ultrasound followed by two chemical procedures: pH control using hydrochloric acid or sodium hydroxide and the addition of sodium hexametaphosphate as a dispersant. The extent of dispersion was determined by quantifying the clay-sized fraction (<2 µm) through gravity sedimentation and the pipette method. The results showed that the content of clay-sized phytoliths in dispersions remained constant from pH 3 to 9, then increased significantly at pH 10–11, likely due to phytolith dissolution, which also led to overestimation of the clay-sized fraction. This finding demonstrated that dispersion at higher pH (>10), as is often the case in PSA methods for soils, is unsuitable for phytoliths; instead, soil particles should be dispersed at pH < 9 to avoid phytolith dissolution.

Modeling dispersed phase holdup and conditions of flooding in a pulsed disc and doughnut solvent extraction column

Modeling dispersed phase holdup and conditions of flooding in a pulsed disc and doughnut solvent extraction column

Global solutions of Euler–Maxwell equations with dissipation

AbstractWe consider the Cauchy problem for a damped Euler–Maxwell system with no ionic background. For smooth enough data satisfying suitable so-called dispersive conditions, we establish the global in time existence and uniqueness of a strong solution that decays uniformly in time. Our method is inspired by the works of D. Serre and M. Grassin dedicated to the compressible Euler system.

A Submicrosecond-Response Ultrafast Microwave Ranging Method Based on Optically Generated Frequency-Modulated Pulses.

An ultrafast microwave ranging method based on optically generated frequency-modulated microwave pulses is proposed in this study. The theoretical analysis demonstrated that nanosecond-scale linear frequency modulation microwave pulse can be obtained by femtosecond laser interference under the condition of unbalanced dispersion, which can be used to achieve a high temporal resolution of the displacement change in the measurement by the principle of frequency modulation continuous wave (FMCW) radar. The proof-of-principle experiment successfully measured the displacement change with an error of 2.5 mm and a range of 0.6 m, with a response time of 468 ns. Compared to existing microwave ranging technologies, the temporal resolution was improved by two orders of magnitude, which greatly improves the temporal resolution of distance measurement in the field of microwave FMCW radar.

Quantifying the Influence of Cloud Seeding on Ice Particle Growth and Snowfall Through Idealized Microphysical Modeling

Cloud seeding is a weather modification technique for enhancing precipitation in arid and semi-arid regions, including the Western U.S. However, designing an optimal cloud seeding operation based on comprehensive evaluation metrics, such as seeding agent dispersion and atmospheric conditions, has yet to be thoroughly explored for this region. This study investigated the impacts of cloud seeding, particularly utilizing silver iodide, on ice particle growth within clouds through numerical modeling. By leveraging the Snow Growth Model for Rimed Snowfall (SGMR), the microphysical processes involved in cloud seeding across five distinct events were simulated. The events were in the Lake Tahoe region, nestled within the Sierra Nevada Mountain ranges in the Western U.S. This model was executed based on six primary variables, including cloud top height, cloud base height, cloud top temperature, cloud base temperature, liquid water content, and ice water content. This study incorporated datasets from the Modern-Era Retrospective Analysis for Research and Applications Version 2 and the Clouds and the Earth Radiant Energy System. The findings revealed the importance of ice nucleation, aggregation, diffusion, and riming processes and highlighted the effectiveness of cloud seeding in enhancing ice particle number concentration, ice water content, and snowfall rates. However, event-specific analyses indicated diverse precipitation responses to cloud seeding based on initial atmospheric conditions. The SGMR modeling hints at the importance of improving ice microphysical processes and provides insights for future cloud seeding research using regional and global climate models.

Street Canyon Vegetation—Impact on the Dispersion of Air Pollutant Emissions from Road Traffic

Roadside vegetation helps to retain air pollutants emitted by road traffic. On the other hand, its presence makes it difficult to ventilate street canyons. The paper examines the influence of vegetation on the dispersion of air pollution generated by road traffic, using the example of two street canyons—both-sided and one-sided street canyons. The study was conducted taking into account the actual emission conditions occurring on the analyzed road sections estimated using the HBEFA methodology. Subsequently, a three-dimensional pollution dispersion model named MISKAM was employed to simulate the air pollutant dispersion conditions in the analyzed street canyons. The modelling results were compared with the measurement data from air quality monitoring stations located in these canyons. The obtained results indicated that the presence of vegetation can significantly impact on the air dispersion of traffic-related exhaust and non-exhaust emissions. The impact of vegetation is more pronounced in the case of a street canyon with dense, high-rise development on both sides than in the case of a street canyon with such development on only one side. The results for the both-sided street canyon demonstrate that the discrepancy between the scenario devoid of vegetation and the scenario with vegetation was approximately 5 µg/m3 (10%) for PM10 and approximately 54 µg/m3 (45%) for NOx, with the former scenario showing lower values than the latter. Nevertheless, the scenario with the vegetation exhibited a lesser discrepancy with the air quality measurements. Vegetation functions as a natural barrier, reducing wind speed in the street canyon, which in turn limits the spread of pollutants in the air, leading to pollutant accumulation near the building walls that form the canyon. Consequently, atmospheric dispersion modelling must consider the presence of vegetation to accurately evaluate the effects of road traffic emissions on air quality in urban areas, particularly in street canyons. The results of this study may hold importance for urban planning and decision-making regarding environmental management in cities aimed at improving air quality and public health.

Qualitative and Quantitative Analyses of Meteorological Impacts on Fine Particle Pollution in Winters of Cold Region in China

Meteorological factors are the key drivers of air pollution. Stable weather conditions, the boundary layer height, and temperature inversion significantly influence the dispersion of particulate matter, which is also associated with the aerodynamic properties of particles. However, limited studies have been conducted on this topic in northeast China. This study investigates the influence of meteorological factors on PM2.5 pollution under cold weather conditions, employing both qualitative and quantitative methods. The key meteorological factors considered include temperature difference, relative humidity, wind speed and direction, the boundary layer height (BLH), and temperature inversion. The stable weather index (SWI) is introduced as a quantitative measure of the stability of weather based on data from the last five winters in a typical megacity of northeast China. The monthly PM2.5 concentrations recorded during the last five Februarys ranged from 59.79 μg/m3 to 85.68 μg/m3, with the highest daily concentration reaching 417 μg/m3. A new parameter, ‘temperature difference (ΔT)’, is defined in this study as the difference in temperature between two consecutive days, calculated by subtracting the previous day’s temperature from the current day’s. The temperature differences were found to have a significantly positive correlation with the differences in PM2.5 concentrations (p &lt; 0.01). The results showed that PM2.5 pollution was associated with increased temperature, higher relative humidity, and lower wind speed, or any combination of these factors. The SWI explained 65% and 64% of the variances in air quality index (AQI) and PM2.5 pollution, respectively. When the predicted SWI exceeds 10, the likelihood of particle pollution increases. A lower BLH, in conjunction with a thicker inversion layer, contributes to the formation of severe particle pollution. In the early stages of a winter pollution episode in Harbin, the temperature inversion layer thickened and intensified, with the inversion top height reaching approximately 200 m. The boundary layer remained below 200 m, resulting in a poor vertical dispersion condition. PM2.5 pollution, therefore, is influenced by the combined effects of multiple meteorological factors. Our study quantitatively analyzed the characteristics of weather conditions and their impacts on air quality, which could provide scientific evidence for air pollution prediction and assist in making specific policy interventions, particularly for the upcoming ninth Asian Winter Games in Harbin in February 2025.

Intra and inter specific variation of propagule settings of the family Rhizophoraceae in the Sundarbans mangrove forest

The Sundarbans mangrove forest in Bangladesh is home to the Rhizophoraceae family, which includes at least 7 species. Understanding the factors influencing mangrove species regeneration in specific areas, such as propagule dispersal, predation, and soil conditions, is crucial for comprehending how these populations establish and grow successfully in changing environments. However, there is limited research on the reproductive phenology of Rhizophoraceae in the Sundarbans. Our research was primarily focused on analyzing and comparing the reproductive phenology of three specific species, Bruguiera sexangula (Lour.) Poir., Rhizophora mucronata Lam., and Kandelia candel (L.) Druce within this diverse ecosystem. We studied the flowering pattern, conversion rate, and growth stages of the reproductive organs of these three species. Both inter- and intra-specific variations in propagule mass and size were also investigated. Our findings revealed that the flowers of these species were present for almost half of the year, with a monthly flowering peak occurring primarily in April and May. The propagule of R. mucronata (60.3 cm) was the longest in size which significantly varied from those of K. candel and B. sexangula. While the diameter and weight of the propagules of B. sexangula and K. candel were similar, they were significantly different from those of R. mucronata. In terms of length and surface area, there were significant variations among the propagules of the studied species. The mean surface area of the propagule was 359.7 cm2 in R. mucronata, 232.8 cm2 in K. candel, and 62.2 cm2 in B. sexangula. Regarding litterfall contribution, reproductive organ production in B. sexangula accounted for 29.1 %, in K.candel it was 37.7 %, and in R.mucronata it was 34.6 %. Our findings suggest that the production of reproductive organs in this mangrove forest is influenced by climatic factors as well as the specific adaptive characteristics of each species rather than solely dependent on the size of the reproductive organs.

Advanced anaerobic digestion by co-immobilization of anaerobic microbes and conductive particles in hydrogel for enhanced methane production performance

Recent research has increasingly focused on the enhancement of anaerobic digestion (AD) through direct interspecies electron transfer (DIET) facilitated by conductive particles (CP). Although this approach can significantly accelerate the AD process, the contact efficiency between CPs and AD microbes is relatively low due to the flow of water in a dispersed condition, leading to possible DIET inefficiency. In this study, a unique approach involving the “co-immobilization” of anaerobic microbes and multi-walled carbon nanotubes (MWCNTs) as CP into a hydrogel matrix was developed to improve the AD process. The advantages of this method include improved contact efficiency between microbes and CPs for enhanced DIET, and increased CP retention within the reactor, thereby omitting the need to compensate for CP washout. The methane production rate for the co-immobilized hydrogel was 2.5-fold and 1.9-fold faster than that of the control (dispersed sludge) and conventional DIET (dispersed sludge with MWCNT addition), respectively. Microbial analysis indicated the enrichment of functional microbes such as Anaerolineacea, Sedimentibacteraceae, Rhodocyclaceae, and Methanothrichaceae, which could be involved in the DIET under co-immobilized conditions. These results demonstrate the potential of the proposed method for realizing an advanced continuous AD process through improved DIET.

Multifold Topological Point with Quadratic Order in Binary Skutterudite Rhodium Triarsenide.

The exploration of topological nodal point states has recently evolved, moving beyond traditional linear crossings to include higher-order dispersions and multifold degeneracies. This study utilizes first-principles calculations to uncover an ideal multifold nodal point of quadratic order in the binary skutterudite rhodium triarsenide. The band structures around this nodal point show not only simple configuration but also clean distribution. Notably, a type-III dispersion condition has also been identified. When considering the effects of spin-orbit coupling, the nodal point retains both its multiple degeneracy and quadratic characteristics, although the band degeneracy transitions from 3-fold to quadruple. Detailed symmetry argument and model analysis have been provided, and precise band surface distribution has been obtained. Furthermore, the material is characterized by multiple significant arc surface states, as confirmed by the projected topological surface states. The clear separation of these states from the bulk bands facilitates experimental investigation. In summary, the multifold nodal point state identified in this research, along with the corresponding material candidate, presents an exceptional platform for the further study of higher-order topological point states, potentially catalyzing advancements in this emerging field.

Research on a 220-GHz modified staggered double corrugated waveguide backward wave oscillator

The output power of a backward wave oscillator (BWO) is limited by the low interaction impedance of a slow wave structure (SWS) when the frequency is in the THz band. A BWO based on modified staggered double corrugated waveguide (MSDCW) SWS is researched as a high-power source operating at THz band to break through the coupling impedance limitation in this paper. The MSDCW-SWS designed for BWO with wide electronic tunable band is optimized by numerical Eigenmode simulation to obtain higher coupling impedance. The simulation results show that the coupling impedance of MSDCW-SWS at 211.5 GHz is 42% higher than that of the original staggered double corrugated waveguide (SDCW) SWS when the dispersion conditions are the same for both SWSs. The sheet beam MSDCW-BWO with a broadband output structure is designed to operate under voltage between 23 and 49 kV and an electron beam current of 160 mA. The 3-D interaction simulation results reveal that more than 80.6 W of average output power can be produced from 210 to 238 GHz and the highest electron efficiency of 2.5% can be obtained at 211.5 GHz. The MSDCW-BWO can be considered a promising high-power THz source.

Optimizing dissolution and dispersion conditions for metal and metal oxide nanoparticles used as antimicrobial agents

Optimizing dissolution and dispersion conditions for metal and metal oxide nanoparticles used as antimicrobial agents

Efficient CO2 Reduction Reaction on Cu-Decorated Biphenylene.

Developing efficient electrocatalysts for CO2 reduction into value-added products is crucial for a green economy. Inspired by the recent experimental synthesis of biphenylene (BPH) and the excellent catalytic activity of copper dispersed on two-dimensional (2D) materials, we chose to systematically investigate the pristine, defective, and Cu-decorated BPH for the electrocatalytic CO2 reduction to value-added hydrocarbons. It is observed that the CO2 molecules bind weakly to the pristine BPH, indicating their chemical inertness. Carbon single-vacancy defects facilitate CO2 adsorption with a strong binding energy (Eb) of -3.23 eV, detrimental to the CO2 reduction reaction (CRR) mechanism. We have further investigated the binding energy and kinetic stability of Cu-decorated BPH as a single-atom-catalyst (SAC). The molecular dynamics simulations confirm the kinetic stability, revealing that the Cu-atom avoids agglomeration under low metal dispersal conditions. The CO2 molecule gets adsorbed horizontally on the Cu-BPH surface with a ΔEb of -0.52 eV. The CRR mechanism is investigated using two pathways beginning with two different initial states, formate (*OCOH) and carboxylic (*COOH). The formate pathway confirms the conversion of *OCOH to *HCOOH with the rate-limiting potential (UL) of 0.39 eV for the production of HCOOH, while for the carboxylic pathway, the conversion of *COH to *CHOH has a UL of 0.32 eV, eventually producing CH3OH. Our findings highlight the role of Cu-BPH as an efficient SAC for CO2 catalytic activity to C1 products, as compared to the state-of-the-art Cu, and holds promise as an electrocatalyst for CRR.

The Seasonality of PM and NO2 Concentrations in Slovakia and a Comparison with Chemical-Transport Model

The air quality (AQ) of a given location depends mostly on two factors: emissions and meteorological conditions. For most places on Earth, the meteorology of an area changes seasonally. For central Europe, winters are associated with poor dispersion conditions, which, in combination with high emissions from local heating systems, lead to significantly higher concentrations than during summer. In this study, the seasonality of AQ is analysed using hourly measurements from 44 monitoring stations in Slovakia for the years 2007–2023 for NO2, PM10 and PM2.5. Two factors are used to evaluate the seasonality—the difference and ratio of the winter and summer mean concentrations. It was found that the seasonal difference has been gradually decreasing for all pollutants since 2017. In the case of PM2.5, the seasonal ratio drops from a value of around 2.5 in 2018 to approximately 1.7 in 2023. While in the past, the seasonal ratio was the highest for PM2.5, in the last three years it is the highest for NO2 with values larger than 2. Our results imply that summer sources of PM emissions start to play a more important role for the AQ than in the past. The observed seasonality was compared with two full-year chemical-transport model simulations.

Two-group interfacial area concentration model for dispersed gas-liquid flows in large-diameter pipes

Interfacial area concentration (IAC) plays a critical role in heat and mass transfers between gas and liquid phases through the interfaces. As interfacial area increases, mass and heat transfers between phases increase. Hence, a reliable IAC estimation is important for two-phase flow numerical simulations to conduct engineering designs and safety analyses. Gas bubbles show different behavior according to their shapes and sizes. Based on the size, gas bubbles can be classified into two groups that show different characteristics, such as IAC. Hence, two-group modeling helps to achieve a general approach for estimating the IAC in bubbly to beyond-bubbly flow regimes. Available models in the literature use empirical correlations to obtain group one and group two void fractions. These empirical approaches are not reliable for different flow conditions. In addition, these models are usually complex with several empirical constants. This study aims to develop a two-group area-averaged IAC model for upward vertical dispersed flows through large-diameter pipes. In addition, this study proposes using a general approach based on the two-group drift-flux model to calculate two-group void fractions rather than applying empirical correlations. The models are evaluated using 156 two-group measured data points in dispersed flow conditions through large-diameter pipes. The resulting prediction errors for group one and group two IAC models are 24.1 % and 34.2 %, and the errors for group one and group two void fraction predictions are 22.8 % and 25.6 %, respectively.

Electrochemical sensor based on a glassy carbon electrode modified with a 3D carbon nanoporous composite for the detection of paracetamol in pharmaceutical samples

With the continued appearance of new drugs, there is a growing interest in the development of new analytical tools to detect and quantify drugs using a simple and reliable way. In this work, we describe the development of an electrochemical sensor based on glassy carbon electrodes modified with a carbon tubular nanocomposite for the detection of paracetamol in pharmaceutical samples. Paracetamol shows a strong adsorption on the electrode surface, which makes possible its determination by adsorptive differential pulse voltammetry in 0.1 mol/L citrate–phosphate pH 5 buffer solution. Optimal conditions for dispersion of carbonaceous material and best conditions for surface adsorption of paracetamol were obtained from experimental designs based on response surface methodology. The high adsorption capacity of paracetamol on the 3D carbon nanoporous composite and the sensitivity of the electrochemical technique employed showed a synergistic effect that allowed reaching a detection limit of 30 nmol L− 1 (4.5 ppb). In addition, the reproducibility and the repeatability were 7 and 5 %, respectively. The paracetamol determination from pharmaceutical samples was performed without pre-treatment of samples. The values of paracetamol founded for different pharmaceutical samples were in a very good agreement with those values obtained from the same samples using HPLC. Therefore, the developed electrochemical sensor is a promising, inexpensive, and easy-to-use tool for the detection and quantification of paracetamol in pharmaceutical samples.

Nanoparticle transport in partially saturated porous media: Attachment at fluid interfaces

Like the solid-water interface (SWI), air-water and oil-water interfaces (AWI and OWI) also act as collectors for nano-sized particles in porous media. The attachment of hydrophobic nanoparticles, which is often favorable and irreversible, is of particular interest because the transport and retention of such particles is closely linked to the fate of nanoplastics in unsaturated subsurface environments and the success of nanoremediation practices. Here, we show how a pore-network model (PNM) can be used to upscale the kinetics and extent of irreversible nanoparticle attachment at a single fluid-fluid interface under conditions of advection and dispersion in a sphere packing. By focusing on a trapped (immobile) non-wetting phase, we highlight a fundamental difference between the single-collector contact efficiency of AWI/OWI and SWI. Namely, AWI/OWI collectors, which are largely by-passed by the flowing aqueous phase, are exposed to a hydrodynamic environment dominated by diffusion. This difference has profound implications for the modelling of nanoparticle transport in porous media at the continuum (Darcy) scale. This study reveals the potential of pore network modelling as an essential complement to continuum models for upscaling the behavior of nanocolloids in porous media.

Assessment and Characterization of Colletotrichum species causing Bitter Rot Disease of Apple in Quetta (Pakistan)

Colletotrichum species present a significant threat and posing a serious threat to the economy of Pakistan. This fact is due to suitable environmental conditions for pathogen dispersal. The research was conducted for the accurate identification of Colletotrichum species and studying its pathogenic behaviour responsible for pre-harvest bitter rot disease of apple fruits in Quetta, Pakistan. For this purpose, a survey was conducted in 2016 2017 across ten locations in Quetta to evaluate the disease assessment and sample collection. The findings revealed disease incidence of 39.22% in 2016 and 32.56% in 2017. Symptoms observed sunken brown lesions, measuring 1-4 cm in diameter, on the fruit surface, containing small, pinhead-sized black fruiting structures. A total of 130 fungal isolates were obtained from infected samples and categorized primarily into three groups (A, B, C) based on distinct cultural and morphological characteristics. Pathogenicity test, conducted in triplicate through spore suspension application on healthy apple fruit, confirmed Colletotrichum as the causative pathogen. Furthermore, ten isolates from each group were subjected to molecular analysis to identify the Colletotrichum species using internal transcribed spacer (ITS), beta-tubulin (TUB), and glyceraldehyde-3 phosphate dehydrogenase (GAPDH) gene regions. From sequence analysis, the fungal isolates were identified as three Colletotrichum species mainly Group (A) C. acutatum (B) C. gloeosporioides and (C) C. siamense. Morphological features act as a primary way of identifying Colletotrichum spp. although it is not feasible due to some Colletotrichum genera being morphologically related, consequently molecular method of identification was sufficient for accurate identification and species confirmation. At our knowledge, tion this is the first comprehensive study of Colletotrichum spp. causing bitter rot disease of apple in Pakistan. The findings of our resesearch will pave the way for future disease management experiments, aiming to prevent this disease becoming a serious threat in the region.

Impact of antiaging additives on the conventional properties of bituminous binder

Aging of binders is a complex phenomenon which reduces the longevity of flexible pavements. Aging involves change in physical, chemical, and morphological properties of binder which makes the binder brittle and highly susceptible to fatigue and thermal cracking. Antiaging additives enhance the service life of flexible pavements by reducing the impact of aging on the performance of binders. An iterative approach is essential to identify the optimal dosage of antiaging additive necessary to counteract the aging effects on binder. The present study aims to evaluate the mixing conditions for uniform dispersion of carbon black and hydrated lime within the binder matrix and thereby evaluate the impact of incorporating these antiaging additives on the conventional properties of binder. For this purpose, varying proportions of carbon black and hydrated lime are added to VG 30 binder and is subjected to softening point, ductility, and penetration tests. The optimal dosage of carbon black and hydrated lime is found to be 6 and 12% respectively based on their significant effects on the conventional properties of the binder. An optimal mixing duration of 60 and 75 min ensures uniform dispersion of carbon black and hydrated lime within the binder matrix at a mixing temperature of 120 °C and a speed of 1000 rpm thereby producing a homogenous binder mastic. Incorporation of antiaging additives up to the optimal dosage enhances the softening point whereas decreases the penetration and ductility of binder. The increase in softening point of binder with incorporation of carbon black and hydrated lime signifies enhanced resistance to rutting and permanent deformation of binder, whereas the reduction in ductility and penetration of binder with incorporation of carbon black and hydrated lime signifies the reduced susceptibility of binder to environmental factors such as temperature fluctuations, UV radiation, and oxidation. The surface texture of the additive influences the ability of binder adsorption, which subsequently affects the rheological properties of binder mastics. Significant improvement in conventional properties of binder with incorporation of carbon black and hydrated lime paves a viable and cost-effective solution for engineering application as it has a subsequent effect on the rheological properties of binder.

A Dibenzo[g,p]chrysene‐Based Organic Semiconductor with Small Exciton Binding Energy via Molecular Aggregation

AbstractExciton binding energy (Eb) is understood as the energy required to dissociate an exciton in free‐charge carriers, and is known to be an important parameter in determining the performance of organic opto‐electronic devices. However, the development of a molecular design to achieve a small level of Eb in the solid state continues to lag behind. Here, to investigate the relationship between aggregation and Eb, star‐shaped π‐conjugated compounds DBC‐RD and TPE‐RD were developed using dibenzo[g,p]chrysene (DBC) and tetraphenylethylene (TPE). Theoretical calculations and physical measurements in solution showed no apparent differences between DBC‐RD and TPE‐RD, indicating that these molecules possess similar properties on a single‐molecule level. By contrast, pristine films incorporating these molecules showed significantly different levels of electron affinity, ionization potential, and optical gap. Also, DBC‐RD had a smaller Eb value of 0.24 eV compared with that of TPE‐RD (0.42 eV). However, these molecules showed similar Eb values under dispersed conditions, which suggested that the decreased Eb of DBC‐RD in pristine film is induced by molecular aggregation. By comparison with TPE‐RD, DBC‐RD showed superior performances in single‐component organic solar cells and organic photocatalysts. These results indicate that a molecular design suitable for aggregation is important to decrease the Eb in films.