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Perlite, a naturally occurring volcanic glass, has gained recognition for its diverse applications across various industries, thanks to its unique physical and chemical properties. This poster review highlights the multifaceted uses of perlite, focusing on its lightweight, porous structure, and excellent thermal insulation and fire resistance. In construction, it serves as an effective thermal insulator and fireproofing material. In horticulture, its porosity enhances soil aeration and water retention, making it ideal for plant growth. Additionally, perlite is utilized in filtration systems due to its ability to remove impurities and contaminants. Its role in the cosmetic industry as a gentle exfoliant and in ceramics as a stress-reducing additive during firing further showcases its versatility. By synthesizing current knowledge of perlite's properties and applications, this review underscores its potential as a sustainable solution in various fields, emphasizing the importance of further research to unlock new innovative uses. [ABSTRACT FROM AUTHOR]

Surface modification via the aryl radicals derived from the de-diazotization reaction of aryldiazonium salts permits an elegant way to modify/functionalize different surfaces. In contrast to other methods (thiols, phosphonic acids, etc) it remains as the most efficient surface modification method regardless of the surface type (metal, semiconductors or insulator) that it can be applied. Although the structure of the modified surfaces by aryl layers is up to now well characterized experimentally by a number of different methods (XPS, Raman, IRRAS, AFM), the interaction of molecules such as oxygen with the formed interface remains up to now unknown. To elucidate how the oxygen molecule interacts onto the Au(111) modified surfaces by aryl groups (phenyl or carboxyphenyl), DFT calculations using Generalized Gradient Approximation (GGA) / DND basis set were performed for Au (111) surface modeled using a 4-layer model (under Periodic Boundary Conditions; cell dimensions: 9.99 Å * 9.99 Å * 7.951 Å with the addition of a 15 Å vacuum layer at the C axis) grafted by phenyl or carboxyphenyl groups. The interaction of the oxygen molecules (in the vacuum and water ? using Conductor like Screening Model) onto the bare and grafted gold surface was evaluated at different positions. The results gave important molecular insights regarding the adsorption energy and geometry induced changes upon the interaction of oxygen molecule onto the grafted interface. [ABSTRACT FROM AUTHOR]

The study of the water/gas bubble interface is essential to understand the interaction of oxygen bubbles produced at working electrode. The formed gas bubbles as observed to migrate against the direction of the electrical field, an indication of their negative charge caused by the hydroxide layer at the bubble/water interface. In this study, the Au surface is grafted by hydrophobic nano-layer (derived from benzenediazonium). Oxygen molecules were generated by applying a positive potential on the tip of the working electrode (a platinum electrode). Afterwards, the SECM tip is approached toward the grafted substrate [Au(111)-phenyl] and the oxygen bubble was squeezed onto the top of the layer and then EIS measurements were obtained. An electrochemical system (EIS) can be modeled by an equivalent circuit. EIS data was analyzed using a Matlab code developed in our group. Electrochemical impedance spectroscopy measurements were achieved by applying an alternating current of 50 mV at 51 frequencies. EIS gave important results regarding the electrochemical behavior of the system. [ABSTRACT FROM AUTHOR]

Surface modification via the aryl radicals derived from the de-diazotization reaction of aryldiazonium salts permits an elegant way to modify/functionalize different surfaces. In contrast to other methods (thiols, phosphonic acids, etc) it remains the only general one vis-à-vis the surface types (metals, semiconductors, and insulators) that it can be applied. Although the structure of the modified surfaces by aryl layers is up to now well characterized experimentally by a number of different methods (XPS, Raman, IRRAS, AFM. . .), the interaction of molecules such as oxygen with the formed interface remains up to now unknown. To elucidate how the oxygen molecule interact on the Au(1 1 1) modified surfaces by aryl groups (phenyl or carboxyphenyl), a Force Field Simulation using The General Utility Lattice Program (GULP) software is performed. Au (111) 4 layer model (at Periodic Boundary Conditions - grafted by one or two aryl groups, either phenyl or carboxyphenyl + oxygen molecule) with dimensions: 8.649 * 8.649 * 20 A vacuum layer at the C axis is used as a surface. The MD simulations with the GULP were performed using ReaxFF 6.0 forcefield, NVT (constant-temperature, constant-volume) canonical ensemble at 298 K. The time step for MD was 1 fs with a total simulation time of 50 ps. For the data analysis, the whole trajectory frames of the MD simulations were used. [ABSTRACT FROM AUTHOR]

Gases emerged from electrochemical reactions at mineral surfaces are produced in the form of bubbles which are created within the reaction system. The electrical properties of gas bubbles are important in determining the interaction of bubbles and the way bubbles interact with other materials, to provide a basis for technical application in many fields. The study of water/gas bubble interface is essential to understand the behavior of the gas in aqueous solution and the interaction of the gas with mineral surfaces in the environment and in technological settings. One of such reactions of interest is the electrochemical splitting of water at hematite surfaces, from which oxygen bubbles are produced. In water or electrolyte condition, gas bubbles are observed to migrate against the direction of the electrical field, indicating them to be negatively charged. This is caused by the hydroxide layer at the bubble/water interface. An electrochemical system can be modeled by an equivalent circuit. In this study, electrochemical impedance spectroscopy (EIS) was used to extract electrochemical parameters affected by time, applied potential on the different substrates and the bubble size on measurements in different pH. By applying EIS, a technique that investigates the frequency-resolved impedance of charge carriers, knowledge about interesting electrochemical processes will be unfolded. [ABSTRACT FROM AUTHOR]