Colloidal Material Research Articles

Colloidal Plasmonic Metasurfaces for the Enhancement of Non‐Linear Optical Processes and Molecular Spectroscopies

AbstractColloidal metasurfaces are emerging as promising candidates for the development of functional chemical metamaterials, combining the undisputed control over crystallography and surface chemistry achieved by synthetic nanochemistry with the scalability and versatility of colloidal self‐assembly strategies. In light of recent reports of colloidal plasmonic materials displaying high‐performing optical cavities, this Minireview discusses the use of this type of metamaterials in the specific context of non‐linear optical phenomena and non‐linear molecular spectroscopies. Our attention is focused on the opportunities and advantages that colloidal nanoparticles and self‐assembled plasmonic metasurfaces can bring to the table compared to more traditional nanofabrication strategies. Specifically, we believe that future work in this direction will express the full potential of non‐linear molecular spectroscopies to explore the chemical space, with a deeper understanding of plasmon‐molecule dynamics, plasmon‐mediated processes, and surface‐enhanced chemistry.

Creative Thinking Skills in Colloidal Material of 11th grade Science Students at SMAN 1 Mempawah Hilir

Creative Thinking Skills in Colloidal Material of 11th grade Science Students at SMAN 1 Mempawah Hilir

Fabrication of rapid sand filter for water treatment using sand and activated carbon

It is pertinent to provide safe drinking water to the people as quality of water keeps deteriorating. According to World Health Organization (WHO), water and hygiene are the primary drivers of public health. Filtration is a water treatment process used for removal of microorganisms and colloidal matters from raw water, therefore this study aims at comparing the effects of sand and activated carbon when used separately in rapid sand filters for water treatment. Fabrication of two models of the rapid sand filters were carried out with 1.2mm stainless steel plates. One of the filters was loaded with gravel (grain size 5mm) at the bottom and this was followed by coarse sand (grain size 3mm) and fine sand (grain size 1mm) at the top. The second filter was loaded with gravel at the bottom and this was followed by coarse sand, fine sand and capped with activated carbon. Raw water, obtained from borehole was stored in a tank and made to pass through each of these filters independently. Sample of the raw water was collected for laboratory analysis in addition to samples of the treated water from each of the two rapid sand filters. The outcomes of the tests reveal that the filtration processes had positive impact on the raw water but the filter capped with activated carbon produced better quality water. The use of activated carbon as the topmost material in a rapid sand filter is recommended as it enhances the quality of treated water in parameters such as colour, conductivity, chloride, hardness, sulphate, total dissolved solids, sodium, magnesium, iron and total plate count. The rapid sand filters would afterwards be used for students’ practical to explain filtration as a water treatment process.

The collapsible nature of reworked residual granites in the Stellenbosch Municipality, South Africa

In South Africa, residual granite is associated with the collapse phenomenon, a geotechnical hazard that was first identified in the 1950s. Residual granite is a product of chemical weathering (in-situ decomposition) or physical weathering of the parent rock (granite) whilst reworked residual granites is defined as residual granite reworked in-situ by termites. Residual granite usually consists of bulky-sized quartz particles, with silts, and bridged by colloidal matter. Extreme leaching of the colloidal matter creates a structure like a honeycomb. It, however, leaves voids within the structure, which affects the mechanical behaviour of the soil. The soil collapses upon wetting under additional loading. Construction on soils with a collapsible fabric has led to many documented problems. This paper, therefore, reports on the examination of mineral composition and particle shape examination and its effect on behavioural changes of potentially collapsible soil. The soil used for this study includes reworked residual granite obtained from the Stellenbosch area in the Western Cape of South Africa. A multi-element analysis and morphological studies were performed on mounts using the ZEISS EVO MA15 scanning electron microscope at the Centre for Analytical Facility at Stellenbosch University. Shape analysis confirmed that the severity of collapse increased with increasing angularity. In addition, the type and amount of clay present at particle contacts influenced the swell and collapse behaviour of reworked residual granite.

Research on the removal of charged colloidal filter materials from coolants in nuclear power plants

In this paper, nano-grade aluminum powder was used as raw material to prepare glass fiber filter material with positive Zeta potential by hydrothermal method. Since colloids of activated corrosion products in primary circuit of nuclear power plant are mainly electronegative, the filter material prepared in this experiment was used to remove colloidal particles in coolant by combining traditional mechanical filtration with electrostatic adsorption, thus improving the removal efficiency of colloidal particles. The leaching problem of soluble silicon in glass fiber filter material was studied. The leaching amount of soluble silicon in glass fiber filter material was decreased while the filtration efficiency was improved. Consequently reduce the risk of safe operation of nuclear power plants.

Influence of Mobile Learning Based on Articulatde Storyline 3 on Colloid Materials on Students' Learning Interest

This research aims to measure students' interest in learning through the use of mobile learning based on storyline 3 on colloidal material. The type of research used is experimental research. The subjects in this research were students in class XI MIPA SMA Negeri 1 Seyagen, totaling 17 students. In this research, students' interest was measured using the Pretest-Posttest technique by administering an interest questionnaire. From the results of the analysis, it is known that there was an increase of 4 students who were promoted from high to very high. The pretest and posttest results of learning interest show that learning using articulate storyline-based learning media has increased students' learning interest by 23.40%. The results of the paired t-test stated that the use of articulate storyline-based learning media was effective in increasing students' interest in learning. This research aims to measure students' interest in learning through the use of mobile learning based on storyline 3 on colloidal material. The type of research used is experimental research. The subjects in this research were students in class XI MIPA SMA Negeri 1 Seyagen, totaling 17 students. In this research, students' interest was measured using the Pretest-Posttest technique by administering an interest questionnaire. From the results of the analysis, it is known that there was an increase of 4 students who were promoted from high to very high. The pretest and posttest results of learning interest show that learning using articulate storyline-based learning media has increased students' learning interest by 23.40%. The results of the paired t-test stated that the use of articulate storyline-based learning media was effective in increasing students' interest in learning.Â

Effect of Creative Problem Solving Models with Ethnoscience on Students’ Problem Solving Ability and Scientific Attitudes

This research aims to analyze whether there are significant differences in problem-solving abilities and scientific attitudes between students who use the ethnoscience-based creative problem-solving learning model and students who use the Discovery learning model on colloidal materials. This research was conducted at SMA N 6 Yogyakarta and SMA N 11 Yogyakarta using a quasi-experimental method with data analysis techniques using MANOVA. Data collection techniques in this research are observation, interviews, questionnaires, and tests. The results showed that there were significant differences in problem-solving abilities and scientific attitudes between experimental class and control class students, with a significance of 0.00 < 0.05 and an effective contribution of 13.6% in the moderate category. Therefore, it can be concluded that the use of a creative problem-solving learning model based on ethnoscience has a significant influence on improving students' chemical problem-solving abilities and scientific attitudes towards colloidal materials.

All-inorganic luminescent solar concentrator based on transparent multicomponent glasses embedded with PbSe QDs

Luminescent solar concentrators (LSCs) have become a seminal technology with the possibility of producing carbon–neutral buildings. However, current LSCs developed based on organic or organic–inorganic strategies face limited long-term outdoor stability. Here we developed an inorganic PbSe QDs glass with a strong UV absorption, large Stokes shift, broadband excitation and emission, and high transparency in the visible range. In addition, the suitability of inorganic PbSe quantum dots (QDs) glasses for use in LSCs as both transparent matrix and luminophore, as an alternative to the combination scheme of organic dyes or colloidal QDs and organic polymer materials was explored. Coupled with a commercial silicon solar cell, the as-prepared transparent LSC exhibited an optical efficiency of 10.13 % and a power conversion efficiency of 1.59 % under standard sunlight. These results demonstrate a new strategy to fabricate stable all-inorganic transparent LSCs for building integrated photovoltaic systems.

Utilization of Tamarind Seed Biocoagulant as Learning Material for Water Purification Practicum in Colloidal System

Discharging wastewater directly into the environment can harm nearby organisms. Efforts to increase environmental awareness, especially about sewage, can be started with educational activities. The study investigates the correlation between chemistry material and water purification using tamarind seed bio coagulant, assessing its feasibility for chemistry experiment design in schools. This research uses descriptive qualitative research. This study described data from observations of water purification using tamarind seedcoagulant, literature studies on chemistry practicum, and interviews with two chemistry teachers and two high school students.The results showed that the relationship between colloidal material and the experiment was to determine the types of products that contain colloidal systems in daily life and the properties of colloids. The results of the chemical parameter test revealed significant changes in the pH levels of river, laundry, and batik wastewater samples, with batik coloring waste showing the most significant changes. The organoleptic test results revealed significant changes in the color, odor, and sediment of batik dyeing wastewater. The protein in tamarind seeds can destabilize substances that cause turbidity. Based on literature studies and interviews, tamarind seed bio coagulant is feasible as a teaching material for chemistry practicum on colloidal system.

Treatment of Urban Wastewater

The evolution of raw wastewater to a purified effluent occurs through various stages or streams that constitute successive purifications. These successive stages of physical, chemical or biological characteristics are combined in order to first eliminate or reduce suspended matter, then colloidal materials and finally dissolved elements, whether mineral or organic. These treatments are distinguished according to the degree of purification sought and the technical means employed; the classification includes: a. Preliminary treatments b. Primary treatments c. Secondary treatments d. Complementary treatments, sometimes referred to as tertiary or advanced treatments The purpose of these purification processes is to obtain a satisfactory effluent for which pollution is limited to such a degree that the discharge does not create any nuisance to the flora or fauna of the receiving environment.

Colloidal quantum dot materials for next-generation near-infrared optoelectronics.

Colloidal quantum dots (CQDs) are a promising class of materials for next-generation optoelectronic devices, such as displays, LEDs, lasers, photodetectors, and solar cells. CQDs can be obtained at low cost and in large quantities using wet chemistry. CQDs have also been produced using various materials, such as CdSe, InP, perovskites, PbS, PbSe, and InAs. Some of these CQD materials absorb and emit photons in the visible region, making them excellent candidates for displays and LEDs, while others interact with low-energy photons in the near-infrared (NIR) region and are intensively utilized in NIR lasers, NIR photodetectors, and solar cells. In this review, we have focused on NIR CQD materials and reviewed the development of CQD materials for solar cells, NIR lasers, and NIR photodetectors since the first set of reports on CQD materials in these particular applications.

PHASE CONCENTRATION EQUILIBRIUM DURING DRYING COLLOID CAPILLARY-POROUS MATERIAL - PEA

In this work, we studied experimentally the phase concentration equilibrium during drying of a colloidal capillary-porous material - peas. The studies were carried out by a static (exsicator) method using saturated aqueous solutions of mineral salts, with the help of which certain relative air humidity was created in the desiccators. To establish equilibrium, the samples were kept in desiccators for one month. The values of relative air humidity over salt solutions at the corresponding temperatures were found from the well-known Schneider diagram. Moisture desorption isotherms were determined, for which high-moisture pea samples were placed in exsicators. The experiments were carried out at three temperatures: 30, 40 and 50 °C. According to the measurement data, moisture desorption isotherms were constructed in the coordinates "relative air humidity - equilibrium moisture content of the material." The resulting desorption isotherms were described by the Henderson equation, for which the values of the coefficients of this equation were found and their statistical evaluation was given. The data on the balance of peas were compared with similar data for other plant colloidal capillary-porous materials: vegetables (carrot and beet cuts), grain crops (rye, wheat and corn grains), and vegetable seeds. A significant influence of the type of culture on the equilibrium moisture content of the material during drying is shown, while the intraspecific influence on the equilibrium moisture content is less important. The obtained data on moisture desorption isotherms during drying can be used for engineering calculations of the kinetics of drying pea grain and for choosing the temperature and humidity conditions for its storage after drying.

Colloidal synthesis of metallodielectric Janus matchsticks.

We present a gram-scale synthesis of metallodielectric Janus matchsticks, which feature a gold-coated silica sphere and a silica rod. SiO2 Janus matchsticks are synthesized in one batch by growing amine-functionalized SiO2 spheres at the end of SiO2 rods. Gold deposition on the spheres produces Au-SiO2 Janus matchsticks with an aspect ratio controlled by the rod length. The metallodielectric Janus matchsticks, produced by scalable colloidal synthesis, hold great potential as functional colloidal materials.

Characteristics and Comparison of Biofilm and Activated Sludge Sewage Treatment Technologies

Sewage treatment is a key environmental protection task and is of great significance to sustainable development. In this paper, biological filter method, rotating biological plate method, traditional push-flow activated sludge method and gradually reduced aeration method are selected to summarize and compare their principles, advantages and disadvantages, and removal objects. Biofilm method is similar to the principle of soil self-purification. It is a kind of aerobic biological treatment technology juxtaposed with activated sludge, and it is a fixed membrane process. The activated sludge is similar to the self-purification principle of water. It is an aerobic biological treatment method for sewage, removing dissolved and colloidal biochemical organic matter from the effluent, as well as suspended solids and other substances that can be adsorbed by activated sludge. It also removes some of the phosphorus and nitrogen. Both methods belong to wastewater biological treatment of suspended microorganisms in the water. They have their advantages, disadvantages and applicable conditions, so there is no competition between the two methods.

Influence of firefighting fluorosynthetic film forming foam on soil microbocenosis

Per- and polyfluoroalkyl substances (PFASs) are a group of over 5000 different chemicals that are used in a wide range of industrial applications and consumer products. Perfluoroalkyl substances have unique properties, such as high chemical stability and surface activity, which leads to their widespread use in medicine, science and everyday life. Aqueous film forming foams (AFFFs) are complex proprietary formulations that contain percent levels of PFASs as well as solvents and hydrocarbon surfactants which, when combined, afford AFFF the functionality required for its purpose. Firefighting foams, such as AFFF, are used primarily to control fires involving flammable liquids such as fuel and oil. AFFF suppresses fire by producing a film over the fuel/oil fire that effectively starves the fire of oxygen. The carbon-fluorine bond makes these compounds extremely strong and stable. This chemical and thermal stability allows these substances to persist in the environment without breaking down. While biological effects of single PFAS have been studied, the effects of PFAS-containing mixtures, such as AFFF, are unknown. The environmental effects of firefighting foam pollutants are generally considered in terms of their toxicity and their biodegradability. Firefighting foams have been found to have a negative impact on the environment (e.g. can remove oxygen from aquatic environment in turn killing aquatic fauna). The effect of PFAS on the microorganisms is not sufficiently studied. To date, there are few studies on the structure and dynamics of microbes in the presence of per- and polyfluoroalkyl substances. Moreover, the results are contradictory. In this regard, it is important to study the impact of various PFAS chemicals on the microorganisms. The article presents the results of the effect study of a fluorosynthetic film forming foam, the main component of which is perfluorinated organic acid, on soil microorganisms, namely ammonifiers, oligonitrophils and nitrogen-fixing microorganisms, yeasts and molds, actinobacteria, and cellulose-degrading bacteria. It was accomplished by plating a sample of the soil that has been serially diluted in water and enumeration of colony forming units (CFU) per gram of soil. The number of soil microorganisms was counted two weeks and three months after contamination with a fluorosynthetic film forming foam. The control sample was unpolluted soil. The sample of soil (1.0 g) was mixed and suspended with a 10 ml of water in a tube for isolation and enumeration of microorganisms. The sample was shaken vigorously to separate organisms from the colloidal material surrounding soil particles. Obtained suspension was serially diluted from 10-2 to 10-6. Aliquot of each dilution was plated onto suitable agar medium. Meat-peptone agar, wort agar, starch-ammonia agar, ashby's agar and hutchinson's agar were used to isolate different groups of microorganisms from gray forest soil and to study the effect of film forming foam on them. The plates were incubated at 28 °C for 3–14 days and the results are expressed as CFU per gram of soil. Colonies of bacteria on meat-peptone agar and ashby's medium were counted after 3–4 days, yeasts and fungi on wort agar after 4–5 days and actinobacteria on starch-ammonia medium after 7–10 days. The number of colonies of cellulose-degrading microorganisms was counted after 14 days cultivation. Firefighting fluorosynthetic film forming foam led to the soil microbial community restructuring and a microbial diversity decrease. The study revealed a decrease the number of different groups of soil microorganisms two weeks after the pollution with the firefighting fluorosynthetic film forming foam, in particular ammonifiers by 2 times compared to the control, nitrogen-fixing microorganisms by 2.7 times, actinobacteria by 4.7 times, yeasts and fungi by 2.8 times. Three months after soil contamination with AFFF the number of nitrogen-fixing microorganisms, actinobacteria, yeasts and fungi increased by 1.85, 1.2 and 2.6 times compared to the control respectively. The number of ammonifiers and cellulose-degrading microorganisms decreased by 1.7 and 5.0 times compared to the control respectively.

(Invited) Integration of Functional Nanostructures and Nanoparticles into Micro- and Nanoelectronic Components and Systems

In recent decades, there has been a significant evolution of microelectronic and semiconductor technologies towards the nanoscale. Both bottom-up and top-down integration concepts of functional nanostructures and nanoparticles into micro- and nanofabricated electronic components have become critical issues that decisively affect the performance of smart electronic systems in various application areas such as environmental sensing and energy harvesting.Functional nanostructures and nanoparticles of different shapes, sizes, morphologies, and materials are now used in various technical and industrial applications, medicine, pharmacy, biology, electronics, power engineering, ecology, and many other fields. However, the complex engineering challenge here is the integration of functional nanostructures, such as molecular components (e.g., functional self-assembled molecular monolayers or entities of desoxyribonucleic acid, DNA), organic or inorganic nanoparticles (metal, semiconductor, colloidal materials), or similar building blocks into nanolithographically fabricated environments.Manufacturing paradigms for this integration go beyond current CMOS- and MEMS-fabrication schemes. Scale-bridging and hybrid manufacturing schemes that combine established top-down manufacturing techniques for microelectronic devices, including aspects of nanotechnology, with bottom-up nanoassembly of molecules on unstructured and pre-structured substrates are required. Microsystems technology based on the combination of conventional semiconductor processing with biotechnological approaches has thus become an emerging field with manifold applications, especially in the field of sensor technology.This contribution describes two illustrative and innovative research questions in nanopatterning and system integration at the micro-nano-interface to motivate applications with new and unprecedented functionalities. The first research question focuses on network-based biocomputing (NBC) using biological agents driven by biomolecular motor proteins in a lithographically fabricated nanofluidic channel system. This approach opens up opportunities for energy-efficient solutions to complex mathematical problems as they make their way through the NBC network. Methods are required to create switchable and rewritable nano-networks to address different mathematical problems using a single NBC-chip. Therefore, stimuli-responsive materials must be selectively and locally deposited into the nano-network to control the transport of the filaments through the network.The second research question focuses on nanophotonic devices based on DNA origami. The high-precision arrangement of nanoscopic substructures using specific binding sites (capture ends) of the DNA origami enables the precise arrangement of DNA origami functionalized with individualized metal nanoparticles. This arrangement could be used to exploit individual spectral response mediated by plasmonic effects.From a technological perspective, top-down lithographic nanostructuring technologies and bottom-up nanostructuring technologies are the basis for new device concepts. The adaptability of nanostructures to the world of biological molecules and other nanoscopic building blocks such as quantum dots and nanoparticles enables novel, even personalized, devices and engineering solutions.

Amphiphilic Low-Molecular-Weight Gelators Bearing β-S-N-Acetylglucosamine Linked to a Tartaric Acid Scaffold: Synthesis, Self-Assembly and Wheat Germ Agglutinin Binding.

The self-assembly of carbohydrate-based amphiphiles can lead to colloidal soft materials such as supramolecular gels featuring highly desirable characteristics like biodegradability and biocompatibility. The report herein presents the synthesis, characterization and supramolecular self-assembly, physical gelation and wheat lectin binding of two structurally related amphiphilic compounds having β-S-N-acetylglucosamine residues linked to a 2,3-diacyl-N,N'-dipropargylated-l-tartaric diamide. A 1-thio-β-N-acetyl-d-glucosamine precursor attached to a conveniently functionalized linker with an azido group was synthesized by means of a one-pot procedure followed by deprotection. A click reaction successfully led to the two amphiphiles, which differed in length of the fatty acid attached to the tartaric acid scaffold. Although both compounds are poorly soluble in water and organic solvents, the difference in terms of hydrophilic moieties provided them with distinct supramolecular gelation properties. While the presence of an octadecyl chain produced a hydrogelator, the dodecadecyl homologue would only form weak gels in DMSO. SEM and rheology experiments confirmed the characteristic fibrillar morphology and viscoelastic properties, in agreement with the presence of physical gels. Both amphiphiles were able to interact reversibly with wheat germ agglutinin (WGA), a lectin that specifically recognizes GlcNAc residues, indicating a potential use in the food industry, as a gluten sensitivity manager, as well as in health-related industries, for example, for drug delivery systems.

Differentiated Project Based Learning to Improve Collaboration Skills and Cognitive Learning Outcomes of High School Students on Colloidal System Material

This research is a Classroom Action Research (CAR) using two cycles, conducted in class XI IPA 1 SMAN 1 Seyegan, Sleman, Yogyakarta which amounted to 36 students. The purpose of CAR is to improve collaboration skills and cognitive learning outcomes of students in class XI IPA 1 at SMA Negeri 1 Seyegan using the Project Based Learning (PjBL) learning model with process and product differentiation. Based on the results of the study, this learning model was able to improve the collaboration skills of students of class XI IPA 1 significantly, namely 17.11%. This learning model is also able to improve the cognitive learning outcomes of students in terms of various aspects, namely the average value, the lowest value, the highest value, the number of students who are complete, and the percentage of classical learning completeness. The average posttest score an increase of 29.38%. Classical learning completeness during the posttest also increased significantly from 22.22% in cycle I to 77.78% in cycle II. This proves that the PjBL learning model with process and product differentiation is able to improve collaboration skills and cognitive learning outcomes of students in class XI IPA 1 at SMAN 1 Seyegan on colloidal system material.

VALIDITY OF DEVELOPMENT OF THE GAME WHO WANTS TO BE A MILLIONAIRE COLLOID IN MAN 3 BANJARMASIN

This study aims to determine the validity of the development of educational game who wants to be a millionaire on colloidal material for class XI students of MAN 3 Banjarmasin with the data source used consists of 1 material expert who is a chemistry teacher and 1 media expert. Data sources used consisted of 1 material expert who is a chemistry teacher and 1 media expert who is a lecturer. who is a lecturer. The type of research used is Research and Development (R&D) model (Define, Design, Develop, and Disseminate). The research results showed that the material expert validation value was 74% and the media expert validation value was 79% so that the game developed could be categorized as valid.

Production Methods Effect on Nanosilica Properties

This study explored nanosilica synthesis using colloidal silica, silica sand, and TEOS, utilizing rotary evaporator drying, sol-gel, and titration methods. It examined the influence of these techniques on silica’s functionalization and mechanical properties. Methacryloxypropyl trimethoxysilane was employed for silanation, with silica characterized using various analytical methods. Particle sizes from SEM images were 19 nm and 14 nm for rotary and sol-gel samples, respectively, while titration samples showed an irregular structure. Zetasizer analysis revealed larger particle sizes. The purity of silica powders ranged from 90% to 99%, and titration samples demonstrated the highest silanability. When used in dental composites, rotary-evaporated silica displayed promising suitability based on its mechanical and physical properties.