Search Results (101)

By synthesizing BiSbO₄ material with a molar ratio of Bi₂O₃ to Sb₂O₃ of 0.6:1 and calcining it at 700 °C, a relatively pure compound was obtained. Additionally, the effects of varying BiSbO₄ content on the microstructure and electrical properties of ZnO varistor ceramics were investigated. Results indicate that as BiSbO₄ content increased from 0% to 3%, the voltage gradient of the varistor rose with increasing BiSbO₄ content while leakage current gradually decreased. The nonlinear coefficient continued to rise, while the residual voltage ratio first decreased then increased. At a BiSbO₄ content of 2%, outstanding electrical properties were achieved: voltage gradient (E_1mA) = 346 V·mm⁻¹, leakage current J_L = 0.14 μA·cm⁻², nonlinear coefficient α = 32, and residual voltage ratio K = 1.73. Furthermore, after undergoing a 100 kA surge, the U_1mA value remained at 93.5% of its initial value, demonstrating outstanding surge stability. This provides a new approach for fabricating high-gradient, high-stability varistors. Full article

A novel catalyst, Tm₂FeSbO₇, was synthesized by employing the solid-phase high-temperature sintering method, and, for the first time, it was utilized to create a Z-type heterojunction with BiYO₃. A direct Z-scheme Tm₂FeSbO₇/BiYO₃ heterojunction photocatalyst (TBHP) was successfully produced by employing the ball-milling technique. X-ray diffraction analysis results indicated that Tm₂FeSbO₇ crystallized in a cubic pyrochlorestructure which owned the Fd-3m space group, with a unit cell parameter of 10.1769 Å, whereas BiYO₃ displayed a fluorite structure in the Fm-3m space group, with a unit cell parameter of 5.4222 Å. The Mossbauer spectrum of Tm₂FeSbO₇ showed that Fe³⁺ ions might locate at octahedral sites. The measured bandgap widths for the TBHP, Tm₂FeSbO_7, and BiYO₃ were 2.14 eV, 2.21 eV, and 2.30 eV, respectively. Multiple experimental results demonstrated that the TBHP exhibited a higher valence band ionization potential, a narrower band gap width, and a higher removal efficiency of the sulfamethoxazole (SMX) compared with the Dy₂TmSbO₇/BiHoO₃ heterojunction photocatalyst. Under visible-light irradiation (VISLI) of 115 min, the TBHP showcased exceptional photocatalytic elimination performance; therefore, the elimination rate of the SMX and the total organic carbon (TOC) mineralization rate reached 99.51% and 98.10%, respectively. In contrast to single-component Tm₂FeSbO₇, BiYO_3, or conventional nitrogen-doped titanium dioxide (N-TiO₂) catalyst, the TBHP exhibited removal efficiency enhancement for degrading the SMX by 1.17 times, 1.31 times, or 4.06 times. Simultaneously, the matching mineralization rate for removing the TOC density by employing the TBHP was 1.20 times, 1.34 times, or 4.73 times higher than that by employing Tm₂FeSbO₇, BiYO₃, or conventional N-TiO₂. Above experimental results indicated that the mineralization efficiency for removing TOC density by employing the TBHP was higher than that by employing Tm₂FeSbO₇, BiYO₃, or N-TiO₂. Radicals trapping experiments and the electron paramagnetic resonance spectroscopy results revealed that hydroxyl radicals, superoxide anions, and photoinduced holes were the primary active species during the catalytic elimination course of the SMX by employing the TBHP under VISLI. The results demonstrated that the direct Z-scheme TBHP, which was developed in this study, exhibited the maximal removal efficiency for degrading the SMX in contrast to Tm₂FeSbO₇, BiYO₃, or N-TiO₂. Additionally, the possible elimination routes and elimination mechanisms of the SMX were proposed. Therefore, an important scientific foundation for developing high-performance heterojunction catalysts was established. Full article

A ceramic anode made of Sb-doped SnO₂ and coated with a photoactive BiPO₄ layer was tested for the (photo)electrochemical oxidation of three commonly used pharmaceuticals: atenolol, ibuprofen, and norfloxacin. Light-pulsed chronoamperometry showed that the photoanode responded immediately to illumination. The application of light and current enhanced degradation for all compounds when treated separately. Ibuprofen and norfloxacin exhibited higher degradation than mineralization, which demonstrates their persistent nature. Electric current was essential to achieve efficient degradation and mineralization, demonstrating the effectiveness of the electrochemical approach. For multicomponent mixtures, applying light resulted in higher mineralization compared to dark conditions at low operation currents (0.2 A). At higher currents (0.4–0.8 A), the contribution of light was partially masked by the enhanced electrochemical production of hydroxyl radicals. The analysis of individual compounds within the mixture revealed significant improvements in degradation under light exposure. Overall, these results demonstrate the potential of the Sb-doped SnO₂ ceramic photoanode as a cost-effective and promising alternative to commercial materials for treating pharmaceutical contaminants. Full article

This study investigates the genesis of gold mineralization at the Rodruin prospect in the central Eastern Desert (CED) of Egypt, with the aim of constraining the relative contributions of metamorphic and magmatic fluids to ore formation. Gold mineralization at Rodruin is hosted by quartz–carbonate veins emplaced within a shear zone that transects low-grade metasedimentary sequences intruded by Ediacaran post-tectonic granitoids. It exhibits characteristics transitional between orogenic turbidite-hosted and polymetallic vein-type mineralization. Although metamorphic devolatilization is interpreted to have generated the dominant ore-forming fluids, adjacent granitoid intrusions acted primarily as a thermal engine, with only a limited direct input of magmatic-hydrothermal fluids. This interpretation is supported by the occurrence of magmatic-affiliated mineral inclusions (monazite, cassiterite, and zircon) coupled with generally low concentrations of trace elements typically enriched in granitic magmatic-hydrothermal fluids (Sb, Bi, Mo, W, Sn, Nb, and Ta), collectively indicating a subordinate magmatic contribution. Rare earth element (REE) patterns of the ore samples closely resemble those of the nearby granitoids, displaying LREE enrichment; however, a distinct positive Eu anomaly is restricted to the ore assemblages and is attributed to hydrothermal feldspar alteration supporting magmatic involvement in ore formation. Carbon and oxygen isotope compositions (δ¹³C = −6.6 to −2.36‰; δ¹⁸O = +15.7 to +19.7‰), together with REE signatures comparable to primitive mantle values and textural evidence for synchronous sulfide–carbonate precipitation, manifested by rhythmic banding of carbonates and sulfides unequivocally indicate a hydrothermal–metasomatic origin. Collectively, these lines of evidence support a hybrid metamorphic–magmatic model in which gold and associated base metals were predominantly transported by metamorphic fluids, whose mobilization and focusing were enhanced by the thermal influence of Younger granitic intrusions, whereas magmatic-hydrothermal fluids contributed only a minor proportion to the overall metal budget. Full article

The six platinum group elements (PGE) are among the rarest elements in the upper continental crust of the earth. Higher values of PGE have been detected in the upper mantle and in chondrite meteorites. The PGE are siderophile and chalcophile elements and are divided into the following: (1) the Ir subgroup (IPGE) = Os, Ir, and Ru and (2) the Pd subgroup (PPGE) = Rh, Pt, and Pd. The IPGE are more refractory and less chalcophile than the PPGE. High concentrations of PGE led, in rare cases, to the formation of mineral deposits. The PGE are carried in discrete phases, the platinum group minerals (PGM), and are included as trace elements into the structure of base metal sulphides (BM), such as pentlandite, chalcopyrite, pyrite, and pyrrhotite. Similarly to PGE, the PGM are also divided into two main groups, i.e., IPGM composed of Os, Ir, and Ru and PPGM containing Rh, Pt, and Pd. The PGM occur both in mafic and ultramafic rocks and are mainly hosted in stratiform reefs, sulphide-rich lenses, and placer deposits. Presently, there are only 169 valid PGM that represent about 2.7% of all 6176 minerals discovered so far. However, 496 PGM are listed among the valid species that have not yet been officially accepted, while a further 641 are considered as invalid or discredited species. The main reason for the incomplete characterization of PGM resides in their mode of occurrence, i.e., as grains in composite aggregates of a few microns in size, which makes it difficult to determine their crystallography. Among the PGM officially accepted by the IMA, only 13 (8%) were discovered before 1958, the year when the IMA was established. The highest number of PGM was discovered between 1970 and 1979, and 99 PGM have been accepted from 1980 until now. Of the 169 PGM accepted by the IMA, 44% are named in honour of a person, typically a scientist or geologist, and 31% are named after their discovery localities. The nomenclature of 25% of the PGM is based on their chemical composition and/or their physical properties. PGM have been discovered in 25 countries throughout the world, with 64 from Russia, 17 from Canada and South Africa (each), 15 from China, 12 from the USA, 8 from Brazil, 6 from Japan, 5 from Congo, 3 from Finland and Germany (each), 2 from the Dominican Republic, Greenland, Malaysia, and Papua New Guinea each, and only 1 from Argentine, Australia, Bulgaria, Colombia, Czech Republic, England, Ethiopia, Guyana, Mexico, Serbia, and Tanzania each. Most PGM phases contain Pd (82 phases, 48% of all accepted PGM), followed, in decreasing order of abundances, by those of Pt 35 phases (21%), Rh 23 phases (14%), Ir 18 phases (11%), Ru 7 phases (4%), and Os 4 phases (2%). The six PGE forming the PGM are bonded to other elements such as Fe, Ni, Cu, S, As, Te, Bi, Sb, Se, Sn, Hg, Ag, Zn, Si, Pb, Ge, In, Mo, and O. Thirty-two percent of the 169 valid PGM crystallize in the cubic system, 17% are orthorhombic, 16% hexagonal, 14% tetragonal, 11% trigonal, 3% monoclinic, and only 1% triclinic. Some PGM are members of a solid-solution series, which may be complete or contain a miscibility gap, providing information concerning the chemical and physical environment in which the mineral was formed. The refractory IPGM precipitate principally in primitive, high-temperature, mantle-hosted rocks such as podiform and layered chromitites. Being more chalcophile, PPGE are preferentially collected and concentrated in an immiscible sulphide liquid, and, under appropriate conditions, the PPGM can precipitate in a thermal range of about 900–300 °C in the presence of fluids and a progressive increase of oxygen fugacity (fO₂). Thus, a great number of Pt and Pd minerals have been described in Ni-Cu sulphide deposits. Two main genetic models have been proposed for the formation of PGM nuggets: (1) Detrital PGM represent magmatic grains that were mechanically liberated from their primary source by weathering and erosion with or without minor alteration processes, and (2) PGM reprecipitated in the supergene environment through a complex process that comprises solubility, the leaching of PGE from the primary PGM, and variation in Eh-pH and microbial activity. These two models do not exclude each other, and alluvial deposits may contain contributions from both processes. Full article

This study focused on the dust in the ventilation of the underground coal mine of Ningwu Coalfield, Shanxi Province; the particle-size distribution and the mineralogical and geochemical characteristics of the vent dust were studied. The particle-size distribution of the vent dusts in the exhaust outlets of the four coal mines studied is similar and characterized by a single peak, which occurred at 3.5–4.0 μm. The minerals in the vent dusts are dominantly composed of kaolinite, followed by illite, quartz, calcite, dolomite, bassanite, and anhydrite. Except for the high content of bassanite, the vent dust discharged from the YS coal mine presents a similar mineral composition to the parent coal. Compared with the parent coal (and the Upper Continental Crust), the vent dust is enriched to varying degrees in the major element oxides Fe₂O₃, CaO, K₂O, Na₂O, and MgO, as well as trace elements Sb, Zn, Bi, Cd, Cu, As, W, and Pb, especially the contents of Sb, Zn, W, and As increased by 1177, 84, 15, and 12 times, respectively. The vent dusts emitted from these coal mines mainly come from the mining of coal seams; a small amount comes from the shotcrete and weathering products of the tunnel gallery, dust flame retardant, and the wear of coal cutters and coal transmission belts. Therefore, it is necessary to strengthen the management of coal mine vent dust emission to ensure that the mine vent emissions are pollution-free. Full article

A novel Z-scheme Dy₂TmSbO₇/BiHoO₃ heterostructure photocatalyst was synthesized with the ultrasound-assisted solvothermal method. The Dy₂TmSbO₇/BiHoO₃ heterojunction photocatalyst (DBHP) reflected wonderful separation efficiency of photogenerated electrons and photogenerated holes owing to the efficient direct Z-scheme heterojunction structure characteristic. The lattice parameter and the bandgap energy of the Dy₂TmSbO₇ were 10.52419 Å and 2.58 eV, simultaneously, the lattice parameter and the bandgap energy of the BiHoO₃ were 5.42365 Å and 2.25 eV, additionally, the bandgap energy of the DBHP was 2.32 eV. Above results indicated that DBHP, Dy₂TmSbO₇ or BiHoO₃ possessed an excellent ability for absorbing visible light energy, therefore, DBHP, Dy₂TmSbO₇ or BiHoO₃ owned superior photocatalytic activity for degrading the sulphamethoxypyridazine (SMP) under visible light irradiation. The removal rate of the SMP after visible light irradiation of 135 min with the DBHP was 99.47% for degrading the SMP during the photocatalytic degradation (PADA) process, correspondingly, the removal rate of the total organic carbon (TOC) concentration after visible light irradiation of 135 min with the DBHP was 98.02% for degrading the SMP during the PADA process. The removal rate of the SMP after visible light irradiation of 135 min with the DBHP was 1.15 times, 1.29 times or 2.60 times that with Dy₂TmSbO₇, BiHoO₃ or nitrogen-doped TiO₂ (N-T). Therefore, the DBHP displayed higher photocatalytic activity for degrading the SMP under visible light irradiation compared with Dy₂TmSbO₇, BiHoO₃ or N-T. Specifically, the mineralization rate for removing the TOC concentration during the PADA process of the SMP with the DBHP was 1.18 times, 1.32 times or 2.79 times that with Dy₂TmSbO₇, BiHoO₃ or N-T. In addition, the stability and reusability of the DBHP were systematically evaluated, confirming that the DBHP owned potential applicability for degrading the antibiotic pollutant, which derived from the practical industrial wastewater. Trapping radicals experiments and the electron paramagnetic resonance measurement experiments were conducted for identifying the reactive radicals, such as the hydroxyl radicals (•OH), the superoxide anions (•O₂⁻) and the photogenerated holes (h⁺), which were generated with the DBHP for degrading the SMP during the PADA process under visible light irradiation, as a result, the •O₂⁻ possessed the maximal oxidative capability compared with the •OH or the h⁺. Above results indicated the degradation mechanism and the degradation pathways which were related to the SMP. In conclusion, this study makes a significant contribution for the development of the efficient Z-scheme heterostructure photocatalysts and provides a key opinion to the development of the sustainable remediation method with the view of mitigating the antibiotic pollution. Full article

A novel series of Gd₂O₃-doped Pb₃O₄–Sb₂O₃–B₂O₃–Bi₂O₃ glasses was synthesized via the conventional melt-quenching technique to explore their structural, thermal, and optical properties for potential photonic and medical phototherapy applications. X-ray diffraction and SEM analyses confirmed the amorphous and homogeneous nature of the samples, while their FTIR spectra revealed characteristic Pb–O, Sb–O, Bi–O, and B–O vibrational bands indicative of a stable glass network. Differential scanning calorimetry (DSC) demonstrated good thermal stability, suitable for high-temperature optical applications. Optical absorption and emission studies indicated the presence of prominent Gd³⁺ ion transitions, with a strong and sharp ultraviolet emission at 311 nm (⁶P_7/2→⁸S_7/2) when excited at 274 nm. The emission intensity and lifetime increased with Gd₂O₃ concentrations of up to 1.0 mol%, beyond which concentration quenching was observed. The optimized composition exhibited a reduced optical band gap and enhanced NB-UVB emission efficiency, suggesting efficient energy transfer with minimal non-radiative losses. These results establish the designed glass system as a promising multifunctional material for NB-UVB-based phototherapy, UV-laser generation, scintillation, and other next-generation photonic devices. Full article

In this study, a novel photocatalytic nanomaterial BiTmFeSbO₇ was successfully synthesized for the first time by using the solvothermal method. On account of the effective Z-scheme mechanism, the BiTmFeSbO₇/BiTmO₃ heterojunction photocatalyst (BTBTHP) could effectively separate the photoinduced electrons and the photoinduced holes, concurrently, the high oxidation potential and reduction potential of the BiTmFeSbO₇ and the BiTmO₃ were retained. Additionally, a Z-scheme BTBTHP was synthesized by using an ultrasound-assisted solvothermal approach. As a result, the BTBTHP exhibited excellent photocatalytic performance during the degradation process of the sulfathiazole (STZ). The morphological features, composition distribution, photochemistry properties and photoelectric properties of the prepared samples were investigated by using the comprehensive characterization techniques. Under the condition of visible light irradiation, the BTBTHP demonstrated an excellent removal efficiency of 99.50% for degrading the STZ. Contrastive analysis results indicated that the removal efficiency of the STZ by using the BTBTHP was substantially higher than that by using the BiTmFeSbO₇, the BiTmO₃, and the N-doped TiO₂. The removal rate of the STZ by using the BTBTHP was 1.14 times that by using the BiTmFeSbO₇, 1.28 times that by using the BiTmO₃, and 2.71 times that by using the N-doped TiO₂. Moreover, the stability and the reusability of the BTBTHP were verified through five successive photocatalytic cyclic degradation experiments, indicating that the BTBTHP owned potential for the practical application. The active species which was produced by the BTBTHP were identified as hydroxyl radicals (•OH), superoxide anions (•O₂⁻), and photoinduced holes (h⁺) by capturing radicals experiments and electron paramagnetic resonance testing experiments. Therefore, the degradation mechanism and the pathway of the STZ could be more comprehensively elucidated. In summary, this study lays a solid foundation for the development and further research of high efficient Z-scheme heterojunction photocatalysts and offers novel insights into sustainable remediation strategies for the STZ pollution. Full article

This study presented the successful synthesis of a visible light responsive Z-scheme BiTmDySbO₇/BiEuO₃ heterojunction photocatalyst (BBHP) via the hydrothermal method, exhibiting outstanding removal efficiency for degrading the metronidazole (MNZ) in wastewater. The BBHP exhibited exceptional photocatalytic activity during the degradation process of the MNZ which was a widely detected pharmaceutical pollutant in aquatic environments. The key to the high photocatalytic activity of the BBHP was the formation of a Z-scheme photogenerated carrier transport channel which existed between BiTmDySbO₇ and BiEuO₃ within the heterojunction structure. This innovative structural design was experimentally confirmed for enhancing the separation efficiency of the photogenerated charge carriers significantly, thereby, the efficient photocatalytic activity of the BBHP was promoted. After visible light irradiation for 130 min, the BBHP achieved a removal efficiency of 99.56% for degrading MNZ and a mineralization rate of 98.11% for removing the total organic carbon (TOC) concentration. In contrast to a single photocatalyst, the removal rate of the MNZ by using the BBHP was 1.14 times that by using the BiEuO₃, 1.26 times that by using the BiTmDySbO₇, and 2.65 times that by using the nitrogen-doped TiO₂ (N-T) under visible light irradiation. The mineralization rate for removing the TOC concentration during the degradation process of the MNZ by using the BBHP was 1.17 times that by using the BiEuO₃, 1.29 times that by using the BiTmDySbO₇, and 2.86 times that by using the N-T under visible light irradiation. The photocatalytic degradation process of the MNZ by using the BBHP followed first-order kinetics model, concurrently, a dynamics rate constant of 0.0345 min⁻¹ was obtained. Furthermore, the BBHP demonstrated excellent stability and durability in accordance with multiple cyclic degradation experiments. According to the capturing radicals experiments and the electron paramagnetic resonance test experiments, it was determined that the hydroxyl radicals (•OH) and the superoxide anions (•O₂⁻) played key role during the photocatalytic degradation process of the MNZ by using the BBHP under visible light irradiation. Finally, the intermediate products that were produced during the degradation process of the MNZ were analyzed by using liquid chromatography-mass spectrometer, as a result, a potential degradation pathway for the MNZ was proposed. Overall, this study could provide valuable references for future research on composite photocatalysts and effectively maintain the safety and sustainable utilization of water resource. Full article

Topological insulators and semimetals are necessary to realize quantum computing and spintronics. We use first-principles calculations to investigate the atomic structure, electronic band structure, and Z${}_2$ invariants of four sets of pure and functionalized buckled hexagonal monolayers that are promising candidates for topological nature: BiAs, AsP, SbAs, BiSb, and functionalized monolayers BiAsX${}_2$, AsPX${}_2$, SbAsX${}_2$, and BiSbX${}_2$ (X = H, O, S). Our results show that BiAsO${}_2$, BiAsS${}_2$, AsPO${}_2$, SbAsO${}_2$, SbAsS${}_2$, BiSbH${}_2$, BiSbO${}_2$, and BiSbS${}_2$ are topological insulators with small SOC-induced band gaps ranging from 0.05 to 0.37 eV. Further, we propose AsPS${}_2$ to be a topological semiconductor. Topological insulators stand on the boundary of induction and conductance and are crucial in realizing quantum computers. The room-temperature topological insulators predicted here will have promising impacts in quantum computing, nanoelectronics, and spintronics. Full article

A pyrochlore-type crystal structure photocatalytic nanomaterial, Ho₂FeSbO₇, was successfully synthesized using a hydrothermal method. Additionally, a fluorite-structured Bi_0.5Yb_0.5O_1.5 was prepared via rare earth Yb doping. Finally, a novel Ho₂FeSbO₇/Bi_0.5Yb_0.5O_1.5 heterojunction photocatalyst (HBHP) was fabricated using a solvothermal method. The crystal structure, surface morphology, and physicochemical properties of the samples were characterized using XRD, a micro-Raman spectrometer, FT-IR, XPS, ultraviolet photoelectron spectroscopy (UPS), TEM, and SEM. The results showed that Ho₂FeSbO₇ possessed a pyrochlore-type cubic crystal structure (space group Fd-3m, No. 227), while Bi_0.5Yb_0.5O_1.5 featured a fluorite-type cubic structure (space group Fm-3m, No. 225). The results of the degradation experiment indicated that when HBHP, Ho₂FeSbO₇, or Bi_0.5Yb_0.5O_1.5 was employed as a photocatalytic nanomaterial, following 140 min of visible light irradiation, the removal efficiency of ciprofloxacin (CIP) reached 99.82%, 86.15%, or 73.86%, respectively. This finding strongly evidenced the remarkable superiority of HBHP in terms of photocatalytic performance. Compared to the individual catalyst Ho₂FeSbO₇, Bi_0.5Yb_0.5O_1.5, or N-doped TiO₂, the removal efficiency of CIP by HBHP was 1.16 times, 1.36 times, or 2.52 times higher than that by Ho₂FeSbO₇, Bi_0.5Yb_0.5O_1.5, or N-doped TiO₂, respectively. The radical trapping experiments indicated that in the CIP degradation process, the hydroxyl radical owned the strongest oxidation ability, followed by the superoxide anion and the photoinduced hole. These studies are of great significance for the degradation of antibiotics and environmental protection. Full article

Complex antimony pyrochlores Bi_2.7M_0.46Ni_0.70Sb₂O_10+Δ (M = Zn, Mg) were synthesized from oxide precursors, using the solid-state reaction method. For each composition variant, the pyrochlore phase formation process was studied during solid-state synthesis in the range of 500–1050 °C. The influence of zinc and magnesium on the phase formation process was established. The interaction of oxide precursors occurs at a temperature of 600 °C and higher, resulting in the formation of bismuth stibate (Bi₃SbO₇) as a binary impurity phase. Oxide precursors, including bismuth(III) and antimony(III,V) oxides, are fixed in the samples up to 750 °C, at which point the intermediate cubic phase Bi₃M_2/3Sb_7/3O₁₁ (sp. gr. Pn-3, M = Zn, Ni) is formed in the zinc system. Interacting with transition element oxides, it is transformed into pyrochlore. An intermediate phase with the Bi_4.66Ca_1.09VO_10.5 structure (sp. gr. Pnnm) was found in the magnesium system. The unit cell parameter of pyrochlore for two samples has a minimum value at 800 °C, which is associated with the onset of high-temperature synthesis of pyrochlore. The synthesis of phase-pure pyrochlores is confirmed by high-resolution Raman spectroscopy. The data interpretation showed that the cations in Ni/Zn pyrochlore are more likely to be incorporated into bismuth positions than in Ni/Mg pyrochlore. The nickel–magnesium pyrochlore is characterized by a low-porosity microstructure, with grain sizes of up to 3 μm, according to SEM data. Zinc oxide has a sintering effect on ceramics. Therefore, the grain size in ceramics is large and varies from 2 to 7 μm. Full article

The aim of this study was to develop an experimental self-etch dental adhesive (SE) by synthesizing graphene oxide–functionalized zirconia (GO-ZrO₂) and hydroxyapatite–functionalized zinc (HA-Zn) as inorganic powders together with bis-GMA _(0–2) (bisphenol A-glycidyl methacrylate) oligomers as main components of the organic matrix. The adhesive was compared to the current gold standard adhesive Clearfill SE Bond 2 (CSE) using cytotoxicity assays, shear bond strength (SBS) tests, and resin–dentin interface analyses. Cytotoxicity assays with human gingival fibroblasts (HGF-1) revealed reduced cell viability at early time points but indicated favourable biocompatibility and potential cell proliferation at later stages. SBS values for the experimental adhesive were comparable to CSE after 24 h of storage while aging did not significantly affect its bond strength. However, SBS exhibited more consistent resin tag formation and higher Weibull modulus values post-aging. A scanning electron microscopy (SEM) analysis highlighted differences in resin tag formation, suggesting the experimental adhesive relies more on chemical bonding than micromechanical interaction. The experimental adhesive demonstrated promising potential clinical properties and bond durability due to the integration of GO-ZrO₂ and HA-Zn fillers into the adhesive. Full article

This review analyzes TiO₂-based coatings formed by the plasma electrolytic oxidation (PEO) process of titanium for the photocatalytic degradation of methyl orange (MO) under simulated solar irradiation conditions. PEO is recognized as a useful technique for creating oxide coatings on various metals, particularly titanium, to assist in the degradation of organic pollutants. TiO₂-based photocatalysts in the form of coatings are more practical than TiO₂-based photocatalysts in the form of powder because the photocatalyst does not need to be recycled and reused after wastewater degradation treatment, which is an expensive and time-consuming process. In addition, the main advantage of PEO in the synthesis of TiO₂-based photocatalysts is its short processing time (a few minutes), as it excludes the annealing step needed to convert the amorphous TiO₂ into a crystalline phase, a prerequisite for a possible photocatalytic application. Pure TiO₂ coatings formed by PEO have a low photocatalytic efficiency in the degradation of MO, which is due to the rapid recombination of the photo-generated electron/hole pairs. In this review, recent advances in the sensitization of TiO₂ with narrow band gap semiconductors (WO₃, SnO₂, CdS, Sb₂O₃, Bi₂O₃, and Al₂TiO₅), doping with rare earth ions (example Eu³⁺) and transition metals (Mn, Ni, Co, Fe) are summarized as an effective strategy to reduce the recombination of photo-generated electron/hole pairs and to improve the photocatalytic efficiency of TiO₂ coatings. Full article