Present work reports the elongation of spherical Ni nanoparticles (NPs) parallel to each other, due to bombardment with 120 MeV Au⁺⁹ ions at a fluence of 5 × 10¹³ ions/cm². The Ni NPs embedded in silica matrix have been prepared by atom beam sputtering technique and subsequent annealing. The elongation of Ni NPs due to interaction with Au⁺⁹ ions as investigated by cross-sectional transmission electron microscopy (TEM) shows a strong dependence on initial Ni particle size and is explained on the basis of thermal spike model. Irradiation induces a change from single crystalline nature of spherical particles to polycrystalline nature of elongated particles. Magnetization measurements indicate that changes in coercivity (H_c) and remanence ratio (M_r/M_s) are stronger in the ion beam direction due to the preferential easy axis of elongated particles in the beam direction.

Irradiation induced damage in materials is highly detrimental and is a critical issue in several vital science and technology fields, e.g., the nuclear and space industries. While the effect of dimensionality (nano/bulk) of materials on its radiation damage tolerance has been receiving tremendous interest, studies have only concentrated on low energy (nuclear energy loss (S_n) dominant) and high energy (electronic energy loss (S_e) dominant) irradiations independently (wherein, interestingly, the effect is opposite). In-fact, research on radiation damage in general has almost entirely focused only on independent irradiations with low and/or high energy particles till date, and investigations under simultaneous impingement of energetic particles (which also correspond to the actual irradiation conditions during real-world applications) are very scarce. The present work elucidates, taking cubic zirconia as a model system, the effect of grain size (26 nm vs 80 nm) on the radiation tolerance against simultaneous irradiation with low energy (900 keV I) and high energy (27 meV Fe) particles/ions; and, in particular, introduces the enhancement in the radiation damage tolerance upon downsizing from bulk to nano dimension. This result is interpreted within the framework of the thermal-spike model after considering (1) the fact that there is essentially no spatial and time overlap between the damage events of the two ‘simultaneous’ irradiations, and (2) the influence of grain size on radiation damage against individual S_n and S_e. The present work besides providing the first fundamental insights into how the grain size/grain boundary density inherently mediates the radiation response of a material to simultaneous S_n and S_e deposition, also (1) paves the way for potential application of nano-crystalline materials in the nuclear industry (where simultaneous irradiations with low and high energy particles correspond to the actual irradiation conditions), and (2) lays the groundwork for understanding the material behaviour under other simultaneous (viz. S_n and S_n, S_e and S_e) irradiations.

Zinc oxide has been the most versatile compound semiconductor, which is applied in diverse streams. Ion beams have been highly sophisticated and innovative tool for material modification and further characterization. In this article, we have systematically reviewed the ion beam synthesis, modification and further applications of ZnO thin films and nanocomposites. ZnO thin films synthesized, using low-energy ion beams, exhibit excellent quality. Ion implantation of ZnO leads to the improvement of electrical, optical and magnetic properties. Inert ion bombardment, on the one hand, results in the formation of uniform surface patterning on ZnO and on the other, produces nucleation centres for nanostructure growth. ZnO thin films also exhibit substantial radiation resistance, thus upon swift heavy ion irradiation, tuning of various properties can be explored with minimal/recoverable damage to the crystal lattice. In a few such studies, room temperature ferromagnetism, dissolution of metal cluster and recrystallization of ZnO have been observed. The precision of energetic ion beams and robustness of ZnO and its nanostructures have been explored for applications such as resistive random access memory, creation of hydrophophic and hydrophilic surfaces and dye degradation.

In the present work, we report on the swift heavy ion induced formation of silver (Ag) nanoparticles (NPs) embedded in the hafnium oxide (HfO₂) matrix. HfO₂ and Ag multilayer thin films have been deposited on both silicon (Si) and quartz substrates to study the irradiation induced structural and optical properties. The evolution of the particle size, shape, and optical properties have been studied by using transmission electron microscopy, grazing incident x-ray diffraction, field emission scanning electron microscope, and UV–Vis absorption spectroscopy. The surface plasmon resonance (SPR) blue shift indicates the effect of the surrounding dielectric on Ag NPs. The present study reveals that the tuning of the wavelength of surface plasmon resonance up to 120 nm with ion fluence is achieved. Thermal spike calculations were employed to estimate the rise of lattice temperature and, subsequently, the diffusivity of metal atoms during temperature spike is estimated.

This work demonstrates the preliminary results of rapid and direct detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) using the quartz crystal microbalance (QCM) method. Coronavirus Disease 2019 (COVID-19)-specific RNA-dependent RNA polymerase (RdRP) gene-dependent probe DNA was used as a selective agent toward target DNA, the inactivated SARS-CoV-2 virus, and RNAs extracted from clinical samples. This study developed and utilised a unique dry-QCM approach with a mitigated experimental procedure. Contact angle measurements, Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS) measurements were employed to investigate the surface during probe immobilisation and target hybridisation. This study also investigates the effect of temperature on probe immobilisation and target hybridisation. The estimated probe density was 0.51 × 10¹² probes/cm², which is below the critical limit. The estimated hybridisation efficiency was about 58.9%. The linear detection range with a Limit of Detection (LoD) was about ~1.22 nM with high selectivity toward SARS-CoV-2 target DNA. The sensor shelf-life was found to be extended to 25 days. The novelty of using a new dry-QCM approach for SARS-CoV-2 detection was proven with the results.