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1

Wpływ nanomodyfikatora TiO₂ na skurcz wczesny betonu

Derda Aleksandra, Jackiewicz-Rek Wioletta

Przegląd Budowlany

|

2026

|

R. 97, nr 2

83--85

PL

Właściwości fotokatalityczne kompozytów cementowych, uzyskuje się m.in. poprzez modyfikację składu dwutlenkiem tytanu (TiO₂). Aby ocenić wpływ tego nanomodyfikatora na właściwości betonu fotokatalitycznego, przeprowadzono badania konsystencji mieszanki betonowej, wytrzymałości na ściskanie oraz skurczu wczesnego. Oznaczenie odkształceń skurczowych wykonano przy użyciu rynny skurczowej, w trakcie pierwszych 72 h po zaformowaniu. Biorąc pod uwagę, że przeważnie badania skurczu rozpoczyna się dopiero 24 h po zaformowaniu, analiza zjawisk występujących w początkowych fazach dojrzewania mieszanki stanowić będzie podstawy do kolejnych badań w tym zakresie.

EN

Photocatalytic properties of cement composites are achieved, among other things, by modifying the composition with titanium dioxide (TiO₂). To assess the effect of this nanomodifier on the properties of photocatalytic concrete, tests were conducted on the concrete mix’s consistency, compressive strength, and early shrinkage. Shrinkage strains were determined using a shrinkage drain during the first 72 hours after molding. Given that shrinkage testing, typically begins 24 hours after molding, analysis of phenomena occurring in the initial stages of mix maturation will provide the basis for further research in this area.

2

Development of low-emission photocatalytic cement composites with co-ground TiO2-fly ash and TiO2-calcium carbonate systems

Ślosarczyk Agnieszka, Klapiszewska Izabela, Jędrzejczak Patryk, Thomas Marta, Klapiszewski Łukasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2026

|

Vol. 74, nr 1

art. no. e155898

EN

This study presents an innovative method for producing low-emission cement composites with photocatalytic properties by partially replacing Portland cement with fly ash, ground granulated blast furnace slag, and calcium carbonate. Novel ground systems combining fly ash-TiO2 or calcium carbonate-TiO2 were synthesized via high-energy ball milling to enhance dispersion and minimize TiO2 agglomeration. The modified composites exhibited improved hydration kinetics, including reduced setting times and up to 50% lower cumulative hydration heat. Mechanical tests confirmed comparable or superior compressive and flexural strengths as compared with the reference materials. All TiO2-containing composites showed UV-induced photocatalytic activity, with anatase-based systems yielding the best results. Carbon footprint analysis confirmed the environmental benefits, particularly in reducing CO2 emissions. These findingssupport the development of multifunctional, sustainable cementitious materials for eco-efficient construction.

3

Antibacterial Properties of Cement Pastes with Addition of Lithium Hydroxide, Cupric Oxide, and Titanium Dioxide

Plaza-Garrido Angela, Imayado-Araya Barbara, Brescia-Norambuena Leonardo

Inżynieria Mineralna

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2025

|

Vol. 2, no. 2

art. no. 1

EN

In order to provide improved functionalities to concrete, new materials are being studied as antibacterial additions. This could result in a reduction in bacteriological hazards bonded to the surfaces of concrete structures, reducing the requirement for cleaning and chloride use. Therefore, this study evaluates the antibacterial action, and the compressive and flexural strength of cement pastes made with different water/cementitious material ratios (0.35, 0.40, and 0.45) and addition percentages of lithium hydroxide (LiOH), cupric oxide (CuO), and titanium dioxide (TiO2) (1%, 3%, 5%, and 10% by weight) separately on Escherichia coli. Antibacterial activity was assessed using inhibition zone measurements, optical density (OD at 600 nm), and colony-forming unit (CFU) counts after exposure to E. coli. Mechanical performance was evaluated through flexural and compressive strength testing at 7 and 28 days. Results show that LiOH decreases the pastes’ strength while producing the highest antibacterial effect due to its high reactivity and pore-inducing behavior; CuO demonstrated the lowest antibacterial effect due to agglomeration issues but increased strength due to its inert nature and filler effect; and TiO2 had an intermediate antibacterial effect with less strength loss than LiOH, although its antibacterial property was not activated by UV require to its photocatalytic mechanism. Also, it was found notable discrepancies between antibacterial assessment methods, highlighting the need for a multi-technique approach to reliably evaluate antimicrobial performance in cement-based materials. Furthermore, the dispersion of microparticles within the paste significantly influenced both antibacterial efficacy and strength development, suggesting that proper mix design and potential use of dispersion aids are critical for industrial applications. As a result, it was concluded that the three compounds could be used as potential additions to concrete to produce an antibacterial effect. Nevertheless, CuO and TiO2 are highly dependent on the dispersion grade, whereas lithium salts are among the best alternatives due to their soluble potential.

4

Experimental investigation of the performance and emission characteristics of cotton seed biodiesel / diesel blends with titanium dioxide nanoparticles

Kumar Dubba Santhosh, Pisini Raminaidu, Kelli Durgaprasad, Bammidi Roopsandeep, Vanam Jaya Prasad, Turali Narayana

Archives of Thermodynamics

|

2025

|

Vol. 46, no. 3

151--161

EN

This study uniquely investigates cotton seed oil as a biodiesel source, a less-explored feedstock, and evaluates the role of TiO2 nanoparticles in enhancing performance and emission characteristics. The use of a variable compression ratio engine under diverse load conditions further distinguishes this work from existing studies on nanoparticle-blended biofuels. The biodiesel was produced via transesterification and blended at various proportions, with and without TiO2 additives. Experimental tests were conducted on a variable compression ratio diesel engine under varying load conditions: one-fourth, half, three-fourths, and full load. The results were compared against conventional diesel fuel. Among the tested blends, B40 (40% biodiesel, 60% diesel) without TiO2 exhibited the highest brake thermal efficiency, exceeding that of diesel by 5.4%, and achieved the highest mechanical efficiency (58.31%) at full load condition. Fuel consumption increased proportionally with load across all fuel types. Notably, B40 without TiO2 also recorded the lowest hydrocarbon emissions, with a reduction of 34 ppm at full load, which corresponds to a 45% decrease compared to conventional diesel. Carbon monoxide emissions were effectively eliminated in TiO2-blended fuels due to improved combustion. Additionally, nitrogen oxides emissions were reduced by 1.1% in B40 when TiO2 was incorporated. Overall, the findings highlight that cotton seed biodiesel, particularly when enhanced with TiO2 nanoparticles, can offer substantial improvements in engine performance and emission control compared to conventional diesel.

5

Titanium Dioxide Production from Low-Grade Ilmenite Ore: Mineral Characterization and Optimization

Supriyatna Yayat Iman, Astuti Widi, Sumardi Slamet, Prasetya Agus, Ginting Lavita Indriani Br., Wahab Wahab, Petrus Himawan Tri Bayu Murti

Archives of Metallurgy and Materials

|

2025

|

Vol. 70, iss. 1

77--86

EN

The characterization of low-grade ilmenite ore from Banten (Indonesia) is investigated, as well as the effects of particle size, NaOH:Ti ratio, and fusion time on Ti and Fe content in TiO2 products. Mineral separation of low-grade ilmenite ore was performed using wet gravity, followed by sieving. Each sample size’s magnetization (using 10,000 Gauss magnets) is followed by weighing the magnetization results. The sifted and magnetized samples were then analyzed with XRF for composition analysis and XRD for compound determination. FE-SEM was applied to analyze morphology. A microscope was used for metalografi analysis. The fusion temperature of the optimization process was determined using STA. Fusion times were 10, 30, 60, 90, and 150 minutes at 850°C, with a NaOH:Ti ratio (w/w) of 1:2, 2:1, and 4:1, and particle sizes of 0.177-0.149 mm, 0.149-0.105 mm, and 0.105-0.074 mm. The minerals ilmenite (FeTiO3), magnetite (Fe3O4), and coesite (SiO2) dominate the characterization of Banten low-grade ilmenite ore. Sixty minutes of fusion at 850°C with a 2:1 NaOH:Ti ratio (w/w) and 0.177-0.149 mm with 94.44% TiO2 in a product was optimal.

6

Synthesis of Brookite Titanium Dioxide Nanorods using Salt-Assisted Ultrasonic Spray Pyrolysis Process and their Photocatalytic Activities

Jeon Hee Yeon, Ji Myeongjun, Hwangbo Young, Lee Gun-Jae, Lee Young-In

Archives of Metallurgy and Materials

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2025

|

Vol. 70, iss. 3

1139--1142

EN

Here, We present the first-ever synthetic method based on the salt-assisted ultrasonic spray pyrolysis process of pure brookite TiO2 nanorods. H2TiF6 and NaNO3 were used as a titanium precursor and salt for the synthesis, the NaNO3 contributes to the individual separation of primary nanostructures and the stabilization of brookite phase generated by the pyrolysis reaction of the precursor in a droplet. The synthesized nanorods were high crystalline and phase purity, as determined by X-ray diffraction and Raman spectroscopy studies. Scanning and transmission electron microscopy investigations showed the effect of the salt addition on the morphological features and the nanorods to have a one-dimensional morphology with an average diameter of about 10 nm. The photocatalytic activity of the synthesized brookite nanorod was tested employing the photodegradation of methylene blue under Xenon lamp irradiation. The results indicated that the brookite nanorod synthesized by salt-assisted ultrasonic spray pyrolysis was superior to commercial anatase nanoparticles.

7

Epoxy-Based Composites Reinforced with MMT and TiO2 Nanoparticles and Supported with the Honeycomb Aramid Core: A Case Study

Stawarz Sylwester

Tribologia

|

2024

|

nr 3

119--132

EN

This work presents the results of investigations into the thermal, dynamic mechanical, and tribological properties of epoxy resin reinforced with titanium dioxide nanoparticles and organically modified montmorillonite in varying proportions. Additionally, reinforcement of an aramid honeycomb core was used to compare the properties of samples with and without the honeycomb structure. A modified T-07 tester was employed to assess the wear resistance of materials and metal coatings during rubbing with loose abrasive. Thermodynamic tests were performed using the three-point bending mode on an Instrument DMA SDTA861 thermal analyzer in the temperature range from 20°C to 140°C. It was found that at an operating temperature of around 57°C, the lowest stiffness was observed in the sample without an aramid core and with 2 vol.% particulate filler in the composite. Tribological tests determined the wear resistance, with composites containing montmorillonite exhibiting the highest wear rates, while the sample with the highest proportion of TiO2 nanoparticles was the most wear-resistant. Notably, the wear rate decreased further when the friction area was along the walls of the aramid honeycomb core.

PL

Praca przedstawia wyniki badań właściwości termicznych, dynamiczno-mechanicznych i tribologicznych żywicy epoksydowej wzmacnianej nanocząstkami tlenku tytanu i organicznie modyfikowaną montmorylonitą w różnych proporcjach. Dodatkowo zastosowano wzmocnienie rdzenia z plastra miodu z aramidu, aby porównać właściwości próbek z rdzeniem i bez niego. Do oceny odporności na zużycie materiałów i powłok metalowych użyto zmodyfikowanego testera T-07. Badania termodynamiczne przeprowadzono w trybie zginania trójpunktowego przy użyciu analizatora DMA SDTA861 w zakresie temperatur od 20°C do 140°C. Stwierdzono, że przy temperaturze roboczej około 57°C najmniejszą sztywność wykazywała próbka bez rdzenia aramidowego i z 2% obj. wypełniacza cząsteczkowego. W badaniach tribologicznych oceniono odporność na zużycie, przy czym kompozyty z montmorylonitem wykazały najwyższe wskaźniki zużycia, a próbka z największym udziałem nanocząsteczek TiO2 była najbardziej odporna na zużycie. Warto zauważyć, że współczynnik zużycia zmniejszał się, gdy obszar tarcia znajdował się wzdłuż ścianek rdzenia aramidowego plastra miodu.

8

Solar-Driven Degradation of Ciprofloxacin in the Aquatic Environment

Sowik Paulina, Kowalska Katarzyna, Felis Ewa

Journal of Ecological Engineering

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2024

|

Vol. 25, nr 3

195--204

EN

Ciprofloxacin (CIP), a pharmaceutical compound, -occurs as a micropollutant in various types of environmental matrices including wastewater, because it is resistant to removal via conventional methods - due to its persistent characteristics. For this reason, in this work the efficiency of photodegradation CIP (2 mg L-1) in Milli-Q water (MW) and tap water (TP) was investigated using TiO2 and ZnO at a concentration of 20 mg L-1 each. The tests were performed without and in the presence of SO42-ions (250 mg L-1) as one of main components of the aquatic, environmental matrices. Solar-driven photocatalysis using TiO2-P25 and ZnO improved the removal efficiency of CIP compared to its solar photolysis. In all cases approximately 90% removal of CIP was observed after 20 to 30 minutes, but no mineralization processes was achieved. The most efficient degradation was obtained using TiO2 at concentration of 20 mg L-1 in DW without the presence of SO42- after 5 minutes. The photodegradation rate constants estimated kt=0.644 min-1 and kQUV=0.249 L kJ-1. The complexity of the matrix affected the efficiency of CIP removal, favouring DW. The impact of sulfate anions also depended on the matrix: in distilled water, their impact was negative on the photocatalysis process efficiency, while in tap water, they slightly accelerated a process of CIP decomposition. Taking this into account, photocatalysis is an efficient; however, further research is necessary.

9

Investigating the Effects of PU-Based Back-Coating with Boric Acid and Titanium Dioxide Additives on Flame Retardancy Levels and Comfort Properties of 100% Cotton Denim Fabric

Öztürkmen Ebru, Güneşoğlu Cem, Topalbekiroğlu Mehmet

Fibres & Textiles in Eastern Europe

|

2024

|

Vol. 32, no. 4

13--21

EN

This study aimed to develop a cost-effective and resource-efficient application to enhance the thermal stability, flame retardancy, self-cleaning, and antibacterial properties of cotton denim fabrics through a single-step, flexible, and simple polyurethane (PU) based back-coating method, ultimately increasing the use of denim fabrics in daily and work clothes thanks to the increased functionality. This method utilizes boric acid (H3BO3) and a binary composite of H3BO3-titanium dioxide (TiO2) as functional additives while considering comfort parameters. Limiting oxygen index (LOI) and vertical burning tests were conducted to explore the thermal stability and flame retardancy of the samples, while assessments of air permeability, water vapour permeability, thermal resistance, and thermal absorptivity were performed to investigate the comfort properties. Comparing two kinds of back-coated denim fabrics, H3BO3-TiO2 back-coated cotton fabric showed the best flame retardancy with the lowest char length (45 mm) and highest LOI (27%). The air permeability values of back-coated fabrics decreased by approximately half compared to the untreated denim fabric. Although the water vapour permeability values decreased, they were less affected by the coating. Coating application reduced thermal conductivity and thermal absorbency, resulting in more thermally resistant denim fabric. This study demonstrates the potential utility of a PU-based coating incorporating TiO2 and H3BO3 on traditional cotton denim fabrics to enhance flame resistance while minimizing any adverse effects on the overall thermal comfort of the fabric.

10

Performance of Graphene Oxide–Titanium Dioxide, Polyethersulphone Membranes for Industrial Wastewater Treatment

Jassim Zahraa Salah, Braihi Auda Jabbar, Shabeeb Kadhum M.

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 9

336--347

EN

The use of hydrophilic polymer membranes derived from nanocomposites for the treatment of industrial wastewaters has garnered significant attention lately. When producing membranes, the fouling problems of these membranes may be lessened by adding hydrophilic additives to the polymer solution. In order to create the membranes by the phase inversion approach, 0.8 weight percent of polyethersulfone (PES) solution was mixed with a combination (1:1) of graphene oxide:titanium dioxide nanoparticles (GO:TiO2 NPs) at various weight percentages (0.2, 0.4, 0.6, and 0). The absence of spectral peaks at 899 and 1669 cm-1 in the completed membranes, as determined by FTIR studies, suggests that the GO:TiO2 NPs component’s hydrolytic breakdown caused the membrane structure’s pores to develop. The membrane topology was rough with a wider range of heights and abnormalities at low NP concentrations, as the histogram of the 3D AFM pictures illustrates. On the other hand, the 2D photos showed that the surface smoothed out and had fewer peaks and valleys at high NP concentrations, which decreased the surface’s roughness. Surface scanning electron microscopy pictures demonstrated that when the membrane’s structure evolved from narrow to broad porosity with uneven expansion of porous patches, adding more nanoparticles increased the water flow. However, cross-sectional SEM pictures showed that the membrane’s constituent parts were a thick porous layer with micropores and elongated finger structures that resembled pores, and a thin skin layer. The membrane’s porosity increased with increasing NP concentration, as demonstrated by porosity calculations and contact angle measurements. This improved selectivity, made the membrane less prone to fouling, and made cleaning safer and easier, particularly for hydrophilic foulants like proteins and polysaccharides. The addition of NPs resulted in an estimated 83% and 92% increase in the flow of pure water and bovine serum albumin (BSA), respectively. However, the BSA rejection initially dropped before increasing once again.

11

The Effect of Palm Char Properties on Malaysian Ilmenite Ores by Carbothermal Reduction

Nasrun Nasha Asyikin, Yunos Nur Farhana Mohd, Idris Muhammad Asri, Halif Norzilah Abdul, Nomura Takahiro

Archives of Metallurgy and Materials

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2024

|

Vol. 69, iss. 4

1491--1499

EN

To identify the mineral grade ore, two distinct Malaysian ilmenite ores (FeTiO3) from different placers deposits were examined. The sources of ilmenite ore were the Kinta Valley in Perak and the Langkawi Black Sand Beach in Kedah. Both of the ores were reduced by palm char as a sustainable carbon reductant. The study examined carbon characteristics and phase transitions following carbothermal reduction at 1550°C. Prior to the studies, the reductant palm char was characterized by XRF, BET surface area measurement, SEM, and ultimate with proximate analyses. It is shown that the palm char had low moisture (4.10 wt.%) and high fixed carbon (75.40 wt.%). The high carbon content, volatile matter, and porous structure of palm char played a significant role in the gas generated during the carbothermal reduction of ilmenite ores. Carbothermal reduction of both ilmenite ores with palm char-produced rutile, iron, titanium carbide, and pseudobrookite. The XRF analysis exhibits the existence of 18.41 and 35.76 wt.% of Fe and TiO2 respectively in Perak ilmenite ore. While Langkawi ilmenite ore shows 9.28 and 22.72 wt.% of Fe and TiO2 respectively.

12

Carbide Cutting Tool Coatings Characterization of 8YSZ

Kareem Shaimaa J., Wurood Asaad M., Abbas Sundus, Al-Ethari Haydar

Advances in Science and Technology. Research Journal

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2024

|

Vol. 18, no. 4

410--419

EN

Using a duplex deposition of TiO2/8YSZ on a carbide cutting tool, a successful sol-gel procedure was achieved, resulting in high homogeneity, good dispersion, and a low average value of surface roughness (223.6)nm. Thermal experiments were done to see how well the coating layers could withstand heat transfer and thermal deterioration. Residual stresses for coated and uncoated carbide cutting tools are measured after thermal shock (thermal shock). Both were immediately chilled in ice water after being heated for 90 minutes for coated inserts and 30 minutes for uncoated inserts at 500, 600, 700, 800, 900, and 1200 °C. For inserts, thermal shock from 900 °C results in significantly different damage mechanisms. The uncoated outside surface is still delineated by a crack network and is surrounded by nearby homogenous cells, but the coated insert (sol gel TBC) in this case really has a few tiny cracks beginning at the edge. The coated insert (sol-gel TBC) fails after being heated to 1200 °C and then cooled in water to freezing which is caused the start of the duplex coating degradation.

13

Ammonia level sensor using tapered optical fiber coated with titanium dioxide-incorporated porphyrin

Parasuti Frazna, Hikmawati Dyah, Trilaksana Herri, Yasin Moh.

Optica Applicata

|

2023

|

Vol. 53, nr 3

353--361

EN

Since ammonia is water-soluble, environmental studies have shown that the industrial waste such as fertilizer manufacturing, food products, palm oil, urea fertilizer industry can cause very serious damage to water body ecosystems if not properly managed, resulting in a decrease in water quality. Devices based on optical technology, especially devices that combine optical fibers and nanomaterials, are identified as highly sensitive to the species of interest by detecting changes in physicochemical properties. A practical, easy-to-use, inexpensive instrument for detecting ammonia level was proposed using tapered optical fiber (TOF) coated with titanium dioxide-incorporated porphyrin. TOF was fabricated by simultaneously stretching and heating. The preparation of TiO2/porphyrin/gelatine was prepared to coat tapered optical fiber by dipping. SEM analysis shows an increase in length and a decrease in diameter, also the successful coating of titanium dioxide and porphyrin in the taper region. The EDX analysis also proves the presence of the Ti element in the TOF layer. The TOF produces significant sensing performances toward the ammonia liquid concentration level. The TOF coated with titanium dioxide-incorporated porphyrin can detect a one ppm difference in ammonia concentration with a certain range of output voltage for every concentration has.

14

A new magnetic-hybrid photoreactor for photocatalytic water disinfection

Paszkiewicz Oliwia, Wang Kunlei, Kordas Marian, Rakoczy Rafał, Kowalska Ewa, Markowska-Szczupak Agata

Chemical and Process Engineering : New Frontiers

|

2023

|

Vol. 44, nr 3

art. no. e22

EN

Environmental contamination is an urgent topic to be solved for sustainable society. Among various pollutants, microorganisms are believed to be the most dangerous and difficult to be completely inactivated. In this research, a new hybrid photoreactor assisted with rotating magnetic field (RMF) has been proposed for the efficient removal of two types of bacteria, i.e., gram-negative Escherichia coli and gram-positive Staphylococcus epidermidis. Three self-synthesized photocatalysts were used, based on commercial titanium(IV) oxide – P25, homogenized and then modified with copper by photodeposition, as follows: 0.5 Cu@HomoP25, 2.0 Cu@HomoP25 and 5.0 Cu@HomoP25 containg 0.5, 2.0 and 5.0 wt% of deposited copper, respectively. The response surface methodology (RSM) was employed to design the experiments and to deteremine the optimal conditions. The effects of various parameters such as copper concentration [% w/w], and treatment time [h] and frequency of RMF [Hz] were studied. Results: analysis of variance (ANOVA), revealed a good agreement between experimental data and proposed quadratic polynomial model (R2 = 0:86 for E. coli and R2 = 0:69 for S. epidermidis). Experimental results showed that with increasing copper concentration, time and decreasing of frequency of RMF, the removal efficiency was increased. Accordingly, the water disinfection efficiency of 100% in terms of the independent variables was optimized, including copper concentration c = 5% and 2.5% w/w, time t = 3 h and 1.3 h and frequency of rotating magnetic field f = 50 Hz and 26.6 for E.coli and S. epidermidis, respectively. This study showed that response surface methodology is a useful tool for optimizing the operating parameters for photocatalytic disinfection process.

15

Simultaneous photooxidation and photoreduction of phenol and Cr(VI) ions using titania modified with nanosilica

Kądziołka Daria, Grzechulska-Damszel Joanna, Schmidt Beata

Polish Journal of Chemical Technology

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2022

|

Vol. 24, nr 4

23--29

EN

The photocatalytic process of phenol oxidation and Cr(VI) reduction in the presence of nano-silica modified titania was carried out. The activity of composites was tested using two different light sources. The photocatalysts with 10% of nanosilica showed the highest activity. The calcination temperature (200–800 °C) significantly determined the sensitivity of the obtained materials to the light source used. Photocatalysts alternately adsorbed and desorbed Cr(VI) ions from the reaction mixture during irradiation. In the one-component mixture, complete oxidation of phenol was observed using material calcined at 650 °C, after 3 h of UV-VIS irradiation. In the reaction mixture of Cr(VI) and phenol, the highest activity was demonstrated by photocatalyst calcined at 300 °C. The concentration of phenol decreased in proportion to the decrease of chromium ions. The obtained titania-silica composites showed oxidizing properties towards phenol and reductive properties toward Cr(VI) ions.

16

Structural and photocatalytic properties of Ni-TiO2 photocatalysts prepared by mechanochemical synthesis assisted with calcination

Kucio Karolina, Charmas Barbara, Zięzio Magdalena, Pasieczna-Patkowska Sylwia

Physicochemical Problems of Mineral Processing

|

2022

|

Vol. 58, iss. 4

art. no. 150348

EN

In the study the mechanochemical synthesis in the planetary ball mill was used to prepare photocatalytic materials obtained on the basis of TiO2 and nickel(II) acetylacetonate as a Ni2+ source. Three materials with different contents of Ni2+: 5, 10 and 20% wt. were prepared. The obtained materials were calcinated at 800°C for 1 h. Their physicochemical properties were investigated using the N2 adsorption/desorption, FT-IR/PAS, XRD, UV-Vis/DRS and SEM methods. Additionally, thermal stability of the obtained materials was examined (TGA/DTG/DTA). Photocatalytic activity of the samples was tested in relation to the aqueous solution of Safranin T (initial concentration C0 = 1×10-5 mol L-1) at the visible light (Vis). The results indicate that the mechanochemical synthesis is an effective and simple method for preparing materials with photocatalytic properties. All obtained materials were characterized by greater photocatalytic activity compared to the initial TiO2.

17

Biological synthesis and characterization of titanium dioxide nanoparticle from Cynodon dactylon

Renitta R. E., Jebaseeli T. J., Dhanaraj A., Paul S.

Journal of Achievements in Materials and Manufacturing Engineering

|

2022

|

Vol. 113, nr 1

31--41

EN

Purpose: There are several advantages of using a biological technique to produce nanoparticles versus a chemical method. The primary goal of this work is to characterize and biologically synthesize titanium dioxide (TiO2) nanoparticles from Cynodon dactylon. The characterization has experimented with UV-Vis Spectroscopy, EDX analysis, SEM, XRD, and FTIR. Design/methodology/approach: The suggested study uses a simple biological technique to accomplish the systematic biological synthesis of TiO2 nanoparticles utilizing Cynodon dactylon plant extract and titanium tetra isopropoxide as a precursor. UV-Vis spectroscopy, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-Ray Diffraction (XRD) are used to confirm the fabrication of the TiO2 nanoparticles. The plant extract as well as titanium-based nanoparticles of the herb, Cynodon dactylon will be tested for its antibacterial activity against human pathogens. This eco-friendly technique for nanoparticle synthesis is straightforward and adaptable to major commercial manufacturing and technological applications. Findings: Cynodon dactylon biosynthesis of TiO2 nanoparticles is efficient, nutrition dependent, does not employ hazardous compounds, and happens at neutral pH levels. The antibacterial study results show that TiO2 nanoparticles synthesized using Cynodon dactylon have good antibacterial properties. TiO2 nanoparticle method of action against bacteria is unknown. This is an alternative process for synthesising TiO2 nanoparticles, apart from other chemical protocols, since this is quick and non-toxic. The antimicrobial property of biologically synthesized TiO2 nanoparticles against Escherichia coli, Staphylococcus aureus, and Acinetobacter baumannii was tested at four different doses of 15 μl/mg, 25 μl/mg, 50 μl/mg, and 75 μl/mg. The present results revealed the 75 μl/mg concentration got the highest zone of inhibition (15, 13, 15 mm) for Acinetobacter baumannii, Staphylococcus aureus, and Escherichia coli. Research limitations/implications: Many nanoparticles smaller than 100 nm are firmly agglomerated with each other in the study. TiO2 nanoparticles absorb in the UV region of 200 to 400 nm. XRD measurements confirmed the presence of TiO2 nanoparticles in the biologically produced sample. In our work, EDX was used to confirm the existence of Ti after its synthesis by Cynodon dactylon. Practical implications: The biosynthesized TiO2 nanoparticles utilizing Cynodon dactylon plant extracts exhibit a good potent antibacterial activity. The proposed results showed that the TiO2 nanoparticles are well suited for biomedical applications. Originality/value: The suggested research identifies several eco-friendly, biological, and cost-effective procedures for manufacturing nano-coated herbal products. The agar well diffusion technique was used to assess antibacterial activities toward test pathogens such as Acinetobacter baumannii, Staphylococcus aureus, and Escherichia coli.

18

Selected properties of polypropylene-TiO2 composites after exposure to UV rays – preliminary study

Olesik Piotr, Peryt Aleksander, Stępień Krzysztof, Frączek Violetta, Mackiewicz Krzysztof, Molka Weronika, Musiał Oliwia, Różańska Weronika, Jesionek Marcin

Composites Theory and Practice

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2022

|

R. 22, nr 1

21--24

EN

In this study the mechanical properties of polypropylene (PP) with a small amount of TiO2, after UV-C exposure were preliminarily analyzed. The effectiveness of titanium oxide was evaluated in two alternative applications: TiO2 as the polymer filler and TiO2 as a protective outer coating. The samples were exposed to UV-C rays for 1000 hours. It was found that an addition of 5 wt.% TiO2 to PP matrix results in a 60% smaller decrease in Rg after 1000 h of exposure to UV-C than in the case of neat polypropylene. It was also found that the addition of TiO2 to the polypropylene matrix is more effective than TiO2 applied as a coating component. The Rg decrease after exposure is about 35% in this case. The research confirmed that TiO2 submicrometric particles seem to be a very good component in reducing the sustainability of polypropylene to UV radiation.

19

Titanium dioxide as a safe additive to sunscreen emulsions

Janczarek Marcin, Szaferski Waldemar

Chemical and Process Engineering

|

2022

|

Vol. 43, nr 4

483-–490

EN

Titanium dioxide with its ability to be a UV light blocker is commonly used as a physical sunscreen in the cosmetic industry. However, the safety issues of TiO2 application should be considered more in-depth, e.g., UV light-induced generation of reactive oxygen species which can cause DNA damage within skin cells. The proper modification of titanium dioxide to significantly limit its photocatalytic properties can contribute to the safety enhancement. The modification strategies including the process conditions and intrinsic properties of titanium dioxide were discussed. The selected examples of commercially available TiO2 materials as potential components of cosmetic emulsions dedicated for sunscreens were compared in this study. Only rutile samples modified with Al2O3 and/or SiO2 showed inhibition of photocatalytic activity.

20

Synthesis of magnesium aluminate spinel doped TiO2 from magnesite waste

Canikoğlu Nuray

Archives of Metallurgy and Materials

|

2022

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Vol. 67, iss. 1

311--316

EN

Magnesium aluminate spinel (MgAl2O4) is an important refractory material of magnesia origin. It is formed by the reaction of magnesium and aluminum oxides. In this study, TiO2 was added to magnesite waste and alumina (Al2O3) powders in different proportions and the mixtures were sintered at different temperatures after shaping. The aim of this study was to produce spinel economically by recycling waste materials. Therefore, titanium dioxide (TiO2) added magnesium aluminate spinel was produced and the products obtained were characterized by XRD and SEM-EDS analyses. In addition, bulk density, apparent porosity and microhardness values were measured and the effects of TiO2 additive on magnesium aluminate properties were examined. The better values were determined in samples doped 4 wt.% TiO2 at the sintering temperature of 1400°C.