Publications
Influence of Solvent Viscosity on TiO2 Nanoparticle Characteristics and TiO2/n-Si Photodetector Performance via Pulsed Laser Ablation in Liquids
Jan 16, 2026Journal Silicon
Publisher Springer Nature Link
DOI https://doi.org/10.1007/s12633-025-03600-4
In this work, we systematically investigated the influence of solvent viscosity on the synthesis, structural properties, and optoelectronic behavior of TiO2 NPs prepared by PLAL. Two distinct liquid environments were selected: Deionized water, characterized by low viscosity, and glycerol, which operates under high viscosity. We analyzed how fluid viscosity affects the morphology, crystallinity, optical response, and device performance of NP. XRD, TEM, and FE-SEM structural and morphological data demonstrate that water-based synthesis facilitates the formation of smaller, anatase-type TiO2 nanoparticles. In contrast, glycerol significantly enlarges the NP size and promotes the coexistence of anatase and rutile phases, as well as aggregates, due to lower cooling rates. Optical data reveal a blue shift in the absorption edge and a larger band gap, measuring 3.76 eV and 3.54 eV, respectively, for NPs derived from Deionized water and glycerol. The NPs were used to fabricate an Al/TiO2/n-Si heterojunction for photodetection studies, showing better performance for glycerol-based NPs, with responsivity measured at 0.185 A/W at 380 nm, a detectivity of 6.24 × 10 11 Jones in the UV range, and an external quantum efficiency exceeding 60%. Thus, this work highlights the importance of solvent viscosity in tailoring NP features and optimizing TiO2-based optoelectronic devices, contributing valuable insights to the sustainable and controlled production of nanoparticle materials for enhanced photodetection.
Hybrid Enhancement of Heat Exchanger Efficiency via Geometric Modifications and Nanofluid-Induced Thermal Property Improvement
Dec 1, 2025Journal Iranian Journal of Chemistry and Chemical Engineering
DOI 10.30492/ijcce.2025.2063613.7153
Issue 3069-3085
Volume Vol. 44, No. 12, 2025
This study numerically investigates the combined heat transfer and fluid flow behavior in a double-pipe heat exchanger enhanced with spring-shaped turbulators and Al₂O₃ nanofluids. Four configurations are analyzed: circular turbulators (Case A), elliptical turbulators (Case B), circular turbulators with nanofluids (Case C), and elliptical turbulators with nanofluids (Case D), all compared against a smooth-pipe baseline. A validated 3D CFD (Computational Fluid Dynamics) model implementing the realizable k-ε turbulence model (y+ ≈ 1) and second-order discretization evaluates key parameters, Nusselt number, friction factor, and thermal performance across Reynolds numbers (3,000 ≤ Re ≤ 20,000). Results demonstrate that elliptical turbulators (Case B) outperform circular designs by 12–45% in heat transfer enhancement, with peak improvements (48.7%) at Re = 3,000, attributed to stronger secondary flows. Nanofluid addition further augments performance, particularly in laminar-transitional regimes, with Case D achieving the highest thermal efficiency. However, enhancements diminish at higher Re (>13,100) as natural turbulence dominates. Pressure drops, penalties increase by up to 211.46 Pa (Case D at Re = 20,000), highlighting a critical trade-off between heat transfer and hydraulic losses. 3D thermal contours reveal that elliptical turbulators create
Synthesis of SnO2 Nanoparticles via Laser Ablation for High-Performance Photodetectors
Apr 29, 2025Journal Plasmonic
Publisher Springer Nature Link
DOI https://doi.org/10.1007/s11468-025-02933-5
Issue October 2025
Volume Volume 20, pages 9191–9202, (2025)
In the present work, tin dioxide nanoparticles (SnO2 NPs) were synthesized using the laser ablation technique and employed in constructing high-performance photodetectors. SnO2 NPs were prepared using Nd:YAG laser pulses 1064 nm ablated on Sn target immersed in deionized water, and the effect of different laser pulse energies such as 300 mJ, 500 mJ, and 700 mJ on the properties of SnO2 NPs was investigated. Optical, structural, and electrical characterizations were performed using UV–VIS spectroscopy, XRD, and TEM. The results have shown that SnO2 NPs ablated at the highest energy produce a good photodetector due to their optimal size, phase, and band gap (Eg). The nanoparticles had a tetragonal rutile phase as confirmed by XRD; the band gap energy gap also increased with low laser energy due to quantum confinement where the energy gap was 4.42 eV, 3.92 eV, and 3.81 eV for 300 mJ, 500 mJ, and 700 mJ, respectively. The photocurrent determined the optoelectronic properties under white light, and the devices belonging to 700 mJ SnO NPs obtained the highest photocurrent density. The spectral responsivity analysis showed that SnO2/n-Si photodetectors exhibit three response bands at ~ 363 nm, ~ 660 nm, and ~ 806 nm, regarding the highest responsivity of 0.19 A/W, 0.25 A/W, and 0.37 A/W, respectively. The results demonstrate that laser ablations are a good green and eco-friendly method for SnO2 NP synthesis suitable for future sustainable energy applications, including renewable energy sources and optical sensing that preserve the environment. This work may suggest that SnO2 NPs may be applied in self-powered photodetectors and efficient solar energy systems to produce green nanomaterials for future energy applications.
Heat transfer enhancement using nanofluids for cooling computer device: a review
Oct 28, 2021Journal NTU JOURNAL OF ENGINEERING AND TECHNOLOGY
Publisher Ministry of Higher Education and Scientific Research - Northern Technical University
DOI https://doi.org/10.56286/ntujet.v1i1.82
Issue First Issue
Volume Vol. 1 No. 1 (2021)
Computer heat dissipation is increasing constantly. This paper discusses a review of computer cooling methods to find the best cooling system. It can be starting with the traditional computer cooling system utilized air then developing it to a liquid cooling system. In the last decade, the nanofluid is attended potentially as a tool for cooling devices especially cooling of computer. It can be summarized the hot topic of cooling devices using nanofluid. The volume fraction and size diameter of nanofluid are significant parameters for utilizing nanofluid with cooling device.