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Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition)

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A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Advanced Nanomaterials and Nanotechnology".

Deadline for manuscript submissions: 20 July 2025 | Viewed by 8717

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Prof. Dr. Radostina Stoyanova

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Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
Interests: solid state chemistry; materials for energy storage; lithium ion batteries; sodium ion batteries; electron paramagnetic resonance spectroscopy; structure characterization; intercalation chemistry
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Dr. Albena Bachvarova-Nedelcheva

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Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Sofia, Bulgaria
Interests: oxide glasses; structural characterization; thermal stability; optical properties; sol–gel synthesis; hybrid materials; photocatalytic properties; antibacterial properties
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Prof. Dr. Ivelina Georgieva

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Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 11 Acad. G. Bonchev Str., 1113 Sofia, Bulgaria
Interests: theoretical and computational chemistry; molecular modeling; molecular and periodic structures; spectroscopis properties; optical materials
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Size-dependent effects in nanostructured materials (nanocrystalline, nanophase, or nanocomposite) are highly significant for both fundamental considerations and contemporary technology. When discussing nanostructured materials, the impact of nanoparticle/nanocrystallite size on surface energy, melting temperature, phase transitions, and phase equilibriums must be taken into consideration. Additional elements, including the non-uniform distribution of grain sizes, residual stresses and pores, interface structure, and grain boundary segregations, also impact the exploration of unresolved problems.

Understanding the size-dependent properties of materials continues to be one of the most challenging issues in advanced materials science. This is largely a result of the technological requirements involved in the development of materials with controlled properties, as well as of the recent progress in materials science, nanotechnology and computational chemistry.

The aim of the present Special Issue is to extend the discussion of the dimensional effects in materials for environmental protection and clean energy production as an innovative approach for the development of innovative materials with improved properties. The issue will comprise (but is not limited to) three main classes of advanced inorganic materials which form the basis of modern technologies:

- Materials and thin films for environmental protection;

- Materials for clean energy storage;

- Ceramics/bioceramics and glasses for better living (with applications in optics, molecular electronics and medicine).

Prof. Dr. Radostina Stoyanova
Dr. Albena Bachvarova-Nedelcheva
Prof. Dr. Ivelina Georgieva
Guest Editors

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

advanced inorganic materials
chemistry of materials
computational chemistry
catalysts/sorbents
electrode materials for rechargeable batteries
hydrogen storage materials
glasses and ceramics
optics
molecular electronics
bio-compatible materials

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Size-Dependent Effects in Materials for Environmental Protection and Energy Application in Materials (22 articles)

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16 pages, 3260 KiB

Open AccessArticle

Catalytic Combustion of Methane over Pd-Modified La-Ce-Zr-Al Catalyst

by Katerina Tumbalova, Zlatina Zlatanova, Ralitsa Velinova, Maria Shipochka, Pavel Markov, Daniela Kovacheva, Ivanka Spassova, Silviya Todorova, Georgi Ivanov, Diana Nihtianova and Anton Naydenov

Materials 2025, 18(10), 2319; https://doi.org/10.3390/ma18102319 - 16 May 2025

Viewed by 107

Abstract

The present study aims to investigate a Pd catalyst on a complex multi-oxide medium-entropy support interlayer La₂O₃-CeO₂-ZrO₂-Al₂O₃ and its possible use as catalysts for methane abatement applications. The low-temperature N₂-adsorption, XRD, TEM, XPS, TPD, and TPR techniques were used to characterize the catalyst. The palladium deposition on the supports leads to the formation of PdO. After the catalytic tests, the metal-Pd phase was observed. The complete oxidation of methane on Pd/La-Ce-Zr-Al catalyst takes place at temperatures above 250 °C, and in the presence of water vapor, the reaction temperature increases to about 70 °C. The careful choice of constituent oxides provides a balance between structural stability and flexibility. The alumina and lanthanum oxide ensure the high specific surface area, while the simultaneous presence of zirconia and ceria leads to the formation of a mixed-oxide phase able to interact with palladium ions by incorporating and de-incorporating them at different conditions. The mechanism of Mars–van Kerevelen was considered as the most probable for the reaction of complete methane oxidation. The possibility of the practical application of Pd-modified La-Ce-Zr-Al catalyst is evaluated. The use of a mix of multiple rare and abundant oxides makes the proposed catalyst a cost-effective alternative. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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18 pages, 4602 KiB

Open AccessArticle

Effect of the Peri-Annulated Dichalcogenide Bridge on the Bipolar Character of Naphthalimide Derivatives Used as Organic Electrode Materials

by Delyana Marinova, Lyuben Borislavov, Silva Stanchovska, Konstantin Konstantinov, Monika Mutovska, Stanimir Stoyanov, Yulian Zagranyarski, Yanislav Danchovski, Hristo Rasheev, Alia Tadjer and Radostina Stoyanova

Materials 2025, 18(9), 2066; https://doi.org/10.3390/ma18092066 - 30 Apr 2025

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Abstract

In recent years, bipolar organic electrode materials have gained recognition as competitive alternatives to inorganic materials due to their unique multielectron redox mechanism for energy storage. In this study, we examined the mechanism of redox reactions in naphthalimide (NI) derivatives when used as electrodes in lithium half-cells with ionic liquid electrolytes. The NI derivatives consist of three building fragments: an aromatic naphthalene core, N-alkylated imide unit, and a peri-dichalcogenide bridge. The integration of electrochemical and microscopic methods with DFT calculations facilitates the delineation of the role of each fragment in the oxidation and reduction reactions of NI derivatives. It is found that the peri-dichalcogenide bridge is mainly involved in the oxidation of NI derivatives above 3.9 V, the charge compensation being achieved by electrolyte TFSI⁻ counter-ions. The reduction of NI derivatives with two Li⁺ ions is mainly due to the participation of the chalcogenide bridge, while after interaction with the next two Li⁺ ions, the imide fragment and the naphthalene moiety contribute equally to the reduction. Based on the leading role of the peri-dichalcogenide bridge, the redox properties of NI derivatives are effectively controlled by the gradual replacement of S with Se and Te atoms in the bridge. To improve the electronic conductivity of NIs, composites with rGO are also synthesized by a simple procedure of mechanical mixing in a centrifugal mixer. The composites rGO/NIs display a good storage performance, the best being the Se-containing analogue. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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15 pages, 2281 KiB

Open AccessArticle

Studies on the Interaction Between the Functional Monomer 4-Methacryloxyethyl Trimellitic Anhydride and Hydroxyapatite and Stability of the Obtained Hybrids

by Vasil Kalchinov, Kostadinka Sezanova, Pavletta Shestakova, Sevda Yantcheva, Radosveta Vasileva and Diana Rabadjieva

Materials 2025, 18(8), 1689; https://doi.org/10.3390/ma18081689 - 8 Apr 2025

Viewed by 279

Abstract

Minimizing the risk of secondary caries in dentistry is achieved by using adhesive systems that provide a strong bond between the natural hard tissue and the restorative material. Evaluating the effectiveness of these systems requires studying both their interaction with dentin and enamel and their behavior in environments with varying acidity. In this work, the interaction of a reactive monomer, 4-methacryloxyethyl trimellitic anhydride (4-META), used in adhesive systems with both dentin-like hydroxyapatite (HA) and hydroxyapatite ceramics, was investigated. Kinetic studies showed that under experimental conditions, 4-META was hydrolyzed and amorphized. Dentin-like HA possessed greater adsorption capacity to 4-META than ceramic HA. Immersion of HA into a solution of 4-META led to formation of an acidic calcium phosphate phase over time in both systems. Studies on the solubility of the synthetic nanosized hydroxyapatite and its derivative with 4-META in 0.1 mol/L lactic acid, also containing CaCl₂, Na₂HPO₄, and NaF (pH 4.5), and in distilled water (pH 6.3) indicated the occurrence of dissolution, complexation, and crystallization processes, causing changes in the liquid and solid phases. The total Ca²⁺ concentration upon dissolution of hybrid HA-4-META in a lactic acid solution was three times lower than the total Ca²⁺ concentration upon dissolution of pure HA. This suggested that 4-META-treated dentin-like surfaces demonstrate greater resistance to dissolution in acidic environments compared to untreated surfaces, highlighting the potential for these hybrids in dental applications. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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16 pages, 3377 KiB

Open AccessArticle

Synthesis, Luminescent and Antibacterial Properties of Sol-Gel TiO₂/TeO₂/Nb₂O₅ Powders

by Kalina Ivanova, Albena Bachvarova-Nedelcheva, Reni Iordanova, Angelina Stoyanova, Petia Petrova, Lilia Yordanova and Iliana Ivanova

Materials 2025, 18(5), 946; https://doi.org/10.3390/ma18050946 - 21 Feb 2025

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The present paper deals with the synthesis, characterization, and properties of sol-gel-derived TiO₂/TeO₂/Nb₂O₅ nanopowders. The gels were prepared using a combination of organic [Ti (IV) n-butoxide, Nb (V) ethoxide (C₁₀H₂₅NbO₅)] and inorganic [telluric acid (H₆TeO₆)] precursors. The aging of gels was performed in air for several days in order to enable further hydrolysis. The phase formation of the gels was investigated by XRD upon heating in the temperature range of 200–700 °C. It was established that the gels heat-treated up to 300 °C exhibited a predominantly amorphous phase in all binary and ternary compositions. The amount of amorphous phase gradually decreased with increasing temperature, and the first TiO₂ (anatase) crystals were detected at about 400–500 °C. The average crystallite size of TiO₂ (anatase) in the powdered samples heat-treated at 400 °C was about 10 nm. By DTA, it was established that the decomposition of organics is accompanied by strong weight loss occurring in the temperature range of 200–300 °C. The completeness of the hydrolysis-condensation reactions was verified by IR and UV–Vis analyses. The UV–Vis spectra of the as-prepared gels exhibited red shifting of the cut-off. Photoluminescence spectra exhibited a change in intensity with varying temperature and composition. The performed photocatalytic tests showed that all powders possess photocatalytic activity toward Malachite green organic dye. The obtained nanopowders exhibited good antibacterial properties against E. coli ATCC 25922. The obtained samples can be considered as prospective materials for use as environmental catalysts. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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20 pages, 6361 KiB

Open AccessArticle

A Highly Efficient Graphene-Based Material for the Removal of Cationic Dyes from Aqueous Solutions

by Paunka Vassileva, Dimitrinka Voykova, Diana Kichukova, Tsvetomila Lazarova, Genoveva Atanasova, Daniela Kovacheva and Ivanka Spassova

Materials 2025, 18(4), 853; https://doi.org/10.3390/ma18040853 - 15 Feb 2025

Viewed by 530

Abstract

Graphene materials and their derivatives have shown promising capabilities in removing anionic and cationic dyes from wastewater. The present study aims at the synthesis of graphene-based material with a high specific surface area and evaluates its use as an adsorbent for removing toluidine blue and methyl violet from aqueous solutions. The physicochemical characterization of the adsorbent before and after dye adsorption is made by XRD, Raman spectroscopy, SEM, TEM, nitrogen physisorption, TG-DTA, and XPS. The influence of the solution’s pH, contact time, dye concentration, and temperature on the adsorption efficiency is investigated. The adsorbent demonstrated high adsorption capacity towards toluidine blue (265.2 mg.g⁻¹) and methyl violet (200.4 mg.g⁻¹) dyes from water. The adsorption process for both dyes follows the Langmuir model and involves physical rather than chemical interactions. Kinetic parameters were also determined. The adsorption of the studied cationic dyes can be attributed to a combination of mechanisms, including electrostatic interactions, hydrogen bonding, and π-π interactions between the dye molecules and the aromatic structure of reduced graphene oxide. The findings in the present work highlight the possibilities for enhancing graphene-based materials’ adsorption capabilities. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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18 pages, 2786 KiB

Open AccessArticle

Graph-Theory Algorithm for Prediction of Electrolyte Degradation Reactions in Lithium- and Sodium-Ion Batteries

by Lyuben Borislavov, Alia Tadjer and Radostina Stoyanova

Materials 2025, 18(4), 832; https://doi.org/10.3390/ma18040832 - 14 Feb 2025

Viewed by 563

Abstract

The growing demand for sustainable energy storage devices requires the fabrication of novel materials for rechargeable metal-ion batteries. The stability of the materials incorporated in the electrochemical cells plays a crucial role in the specific capacity and cycling stability of energy storage devices. The processes that occur inside such systems are fairly complex; hence, the identification of unwanted side reactions affecting the electrochemical stability is not a trivial task. The present study combines cheminformatics and quantum chemistry approaches to create an algorithm that generates diverse viable side products of redox reactions that a given electrochemical system, e.g., different cathode or anode materials, electrolytes, solvents, etc., can undergo. Two case studies of electrolyte degradation are presented: namely, ethylene carbonate (EC) and diglyme (DG). The effect of the electrode surface is modeled by the dehydrogenation reactions of the electrolyte solvents. The predicted degradation products after reduction and oxidation are validated using previously reported experimental data. For EC, the predicted products are CO, CO₂, ethene, ethylene oxide, [CO₂]^•−, and [CO₂]^•+, while for DG alkoxy anions are mainly anticipated. The number of gaseous products formed upon DG degradation is significantly smaller than the number of gaseous species formed by EC fragmentation. The proposed algorithm opens new avenues for the rapid deduction of degradation products of novel electrolyte solvents for which no experimental data are available and can easily be adapted to predict the degradation of other materials. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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15 pages, 6155 KiB

Open AccessArticle

Nanoparticle-Composed Photosensitive Thin Films Based on ZnO

by Tina Dilova, Anna Dikovska, Aleksandra Baeva, Genoveva Atanasova, Georgi Avdeev, Tsanislava Genova and Nikolay Nedyalkov

Materials 2024, 17(23), 5773; https://doi.org/10.3390/ma17235773 - 25 Nov 2024

Viewed by 771

Abstract

In this work, atmospheric pulsed laser deposition was used to prepare photosensitive elements. This technology is a practical and relatively inexpensive way of obtaining highly porous nanostructures composed of nanoparticles or nanoaggregates characterized by a large surface-to-volume ratio. Samples were produced via laser nanosecond or picosecond laser ablation of pure ZnO or mixed ZnO-TiO₂ targets on quartz substrates with pre-deposited gold electrodes. The structure, morphology, optical, and electrical properties of the nanostructures obtained were studied regarding the sample composition and laser ablation regime applied. The ablation of a mixed ZnO-TiO₂ target led to the fabrication of composite samples consisting of ZnO and Zn₂TiO₄ nanoparticles. The electrical properties of pure and composite samples were studied under exposure to UV light irradiation. It was found that the photosensitive properties of the samples depended on the ablation regime applied. The dark current measured for the nanosecond-deposited samples was a few nA, which was an order of magnitude larger compared to the picosecond-deposited samples. The value of the photogenerated current of the nanosecond-deposited samples was 10³-times higher than that of the picosecond-deposited samples. This is due to the lower absorption of the picosecond-deposited samples, as well as to the presence of defect-related radiative recombination in the picosecond-deposited samples, which limits the photocurrent rise. The estimated rise and decay times were longer for the composite samples independently of the deposition regime applied. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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17 pages, 4677 KiB

Open AccessArticle

Influence of Phase Composition and Morphology on the Calcium Ion Release of Several Classical and Hybrid Endodontic Cements

by Ivanka Dimitrova, Galia Gentscheva, Ivanka Spassova and Daniela Kovacheva

Materials 2024, 17(22), 5568; https://doi.org/10.3390/ma17225568 - 14 Nov 2024

Viewed by 842

Abstract

The ability of the cement to release calcium ions, which participate in the remineralization of dentin by forming apatite which improves root canal sealing with time, is of particular importance. Five recently introduced calcium-silicate commercial dental cements were investigated with a view to the influence of the physicochemical characteristics on the possibility of releasing calcium ions in an aqueous medium. Two hybrid calcium-silicate cements in the form of a paste-like ready mix (BioCal^® Cap and TheraCal LC) and three calcium-silicate cements consisting of two components—powder and liquid (Harvard MTA Universal, Rootdent, and BioFactor) were subjected to powder XRD, SEM, and EDS for detailed examination. The cements were immersed in water for 28 days and the phase composition and morphology of the cements before and after soaking were studied. The total calcium release for each cement was determined by ICP-OES. BioFactor and BioCal^® Cap release the highest amount of calcium ions, while the lowest release is registered with Rootdent and TheraCal LC. The PDT treatment of BioFactor does not influence substantially the calcium release. The impact of the elemental and phase composition on the calcium release and calcium carbonate formation was discussed. A reciprocal relation between the aluminum content and the quantity of the released calcium has been found. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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21 pages, 9532 KiB

Open AccessEditor’s ChoiceArticle

Dual-Function Femtosecond Laser: β-TCP Structuring and AgNP Synthesis via Photoreduction with Azorean Green Tea for Enhanced Osteointegration and Antibacterial Properties

by Marco Oliveira, Liliya Angelova, Liliana Grenho, Maria Helena Fernandes and Albena Daskalova

Materials 2024, 17(20), 5057; https://doi.org/10.3390/ma17205057 - 16 Oct 2024

Viewed by 1367

Abstract

β-Tricalcium phosphate (β-TCP) is a well-established biomaterial for bone regeneration, highly regarded for its biocompatibility and osteoconductivity. However, its clinical efficacy is often compromised by susceptibility to bacterial infections. In this study, we address this limitation by integrating femtosecond (fs)-laser processing with the concurrent synthesis of silver nanoparticles (AgNPs) mediated by Azorean green tea leaf extract (GTLE), which is known for its rich antioxidant and anti-inflammatory properties. The fs laser was employed to modify the surface of β-TCP scaffolds by varying scanning velocities, fluences, and patterns. The resulting patterns, formed at lower scanning velocities, display organized nanostructures, along with enhanced roughness and wettability, as characterized by Scanning Electron Microscopy (SEM), optical profilometry, and contact angle measurements. Concurrently, the femtosecond laser facilitated the photoreduction of silver ions in the presence of GTLE, enabling the efficient synthesis of small, spherical AgNPs, as confirmed by UV–vis spectroscopy, Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FTIR). The resulting AgNP-embedded β-TCP scaffolds exhibited a significantly improved cell viability and elongation of human bone marrow mesenchymal stem cells (hBM-MSCs), alongside significant antibacterial activity against Staphylococcus aureus (S. aureus). This study underscores the transformative potential of combining femtosecond laser surface modification with GTLE-mediated AgNP synthesis, presenting a novel and effective strategy for enhancing the performance of β-TCP scaffolds in bone-tissue engineering. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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14 pages, 8182 KiB

Open AccessArticle

The Influence of High-Energy Milling on the Phase Formation, Structural, and Photoluminescent Properties of CaWO₄ Nanoparticles

by Reni Iordanova, Maria Gancheva, Iovka Koseva, Peter Tzvetkov and Petar Ivanov

Materials 2024, 17(15), 3724; https://doi.org/10.3390/ma17153724 - 27 Jul 2024

Cited by 1 | Viewed by 1027

Abstract

CaWO₄ nanoparticles were obtained by facile mechanochemical synthesis at room temperature, applying two different milling speeds. Additionally, a solid-state reaction was employed to assess the phase composition, structural, and optical characteristics of CaWO₄. The samples were analyzed by X-ray diffraction (XRD), transition electron microscopy (TEM), and Raman, infrared (IR), ultraviolet–visible (UV–Vis) reflectance, and photoluminescence (PL) spectroscopies. The phase formation of CaWO₄ was achieved after 1 and 5 h of applied milling speeds of 850 and 500 rpm, respectively. CaWO₄ was also obtained after heat treatment at 900 °C for 12 h. TEM and X-ray analyses were used to calculate the average crystallite and grain size. The Raman and infrared spectroscopies revealed the main vibrations of the WO₄ groups and indicated that more distorted structural units were formed when the compound was synthesized by the solid-state method. The calculated value of the optical band gap of CaWO₄ significantly increased from 2.67 eV to 4.53 eV at lower and higher milling speeds, respectively. The determined optical band gap of CaWO₄, prepared by a solid-state reaction, was 5.36 eV. Blue emission at 425 (422) nm was observed for all samples under an excitation wavelength of 230 nm. CaWO₄ synthesized by the solid-state method had the highest emission intensity. It was established that the intensity of the PL peak depended on two factors: the morphology of the particles and the crystallite sizes. The calculated color coordinates of the CaWO₄ samples were located in the blue region of the CIE diagram. This work demonstrates that materials with optical properties can be obtained simply and affordably using the mechanochemical method. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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23 pages, 6508 KiB

Open AccessEditor’s ChoiceArticle

The Influence of the Alkylamino Group on the Solvatochromic Behavior of 5-(4-substituted-arylidene)-1,3-dimethylpyrimidine-2,4,6-triones: Synthesis, Spectroscopic and Computational Studies

by Ilona Pyszka, Przemysław Krawczyk and Beata Jędrzejewska

Materials 2024, 17(10), 2447; https://doi.org/10.3390/ma17102447 - 19 May 2024

Cited by 1 | Viewed by 1112

Abstract

Advances in electronics and medical diagnostics have made organic dyes extremely popular as key functional materials. From a practical viewpoint, it is necessary to assess the spectroscopic and physicochemical properties of newly designed dyes. In this context, the condensation of 1,3-dimethylbarbituric acid with electron-rich alkylaminobenzaldehyde derivatives has been described, resulting in a series of merocyanine-type dyes. These dyes exhibit intense blue-light absorption but weak fluorescence. An electron-donating alkylamino group at position C4 is responsible for the solvatochromic behavior of the dyes since the lone electron pair of the nitrogen atom is variably delocalized toward the barbituric ring, which exhibits electron-withdrawing properties. This was elucidated, taking into account the different geometry of the amino group. The intramolecular charge transfer in the molecules is responsible for the relatively high redshift in absorption and fluorescence spectra. Additionally, an increase in solvent polarity moves the absorption and fluorescence to lower energy regions. The observed solvatochromism is discussed in terms of the four-parameter Catalán solvent polarity scale. The differences in the behavior of the dyes were quantified with the aid of time-dependent density functional theory calculations. The obtained results made it possible to find regularities linking the basic spectroscopic properties of the compounds with their chemical structure. This is important in the targeted search for new, practically important dyes. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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Review

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21 pages, 320 KiB

Open AccessReview

Stripping Voltammetry in Trace Ga(III) Analysis Using Different Working Electrodes: A Review

by Malgorzata Grabarczyk, Edyta Wlazlowska and Marzena Fialek

Materials 2025, 18(4), 769; https://doi.org/10.3390/ma18040769 - 10 Feb 2025

Viewed by 569

Abstract

Heavy metal contamination of water has become a global environmental problem in recent years, which is caused by the rapid development of economies and industries. Gallium is of enduring interest because of its wide range of applications in technology and industry. In its pure form or as a component of alloys, gallium is used in devices such as high-current switches, pressure gauges, and thermometers. Gallium compounds also play an important role in electronics and optoelectronics, particularly in devices that operate in the infrared range. Gallium isotopes are also used in medical diagnostics. The increasing demand for gallium emphasizes the need for accurate methods for its determination in different matrices. One method used for this purpose is stripping voltammetry. The working electrodes, complexing agents, and the influence of interferences on the accuracy of the measurement are discussed in detail, highlighting their crucial role in obtaining the analytical signal of gallium in procedures based on stripping voltammetry. Voltammetric procedures for the simultaneous determination of gallium and other metal ions are also described. The application of the developed procedures to the analysis of real samples is emphasized as crucial for environmental monitoring and the accurate determination of trace concentrations of gallium. A summary of the results is presented in the form of a table which provides detailed information on the stripping voltammetry methods, including the types of working electrodes, characteristics of the substrate electrolytes used, complexing agents, linear ranges, and detection limits. The table also includes accumulation times, interferences investigated, and practical applications of the methods discussed, making it a valuable resource for researchers and analysts involved in environmental analysis. The review highlights the importance of this technique as an accurate and sensitive tool for the analysis of gallium in environmental samples. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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