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This report investigates the effect of substrate and nitrogen (16 keV N+) ion implantation on the structural, morphological, compositional, and electrical properties of V2O5 thin films which are grown by thermal evaporation on various substrates, including glass, Si, and sapphire (termed V2O5:Gl, V2O5:Si, and V2O5:Sp, respectively). Structural analysis showed the formation of the mixed (α, and β-V2O5) phases on all substrates; however, the β-V2O5 phase is highly dominant in the V2O5:G and V2O5:Si samples. A deformation in the β-phase of V2O5 thin film under ion implantation-induced strain results in a change of crystallite size. Irradiation suppresses XRD peaks in relative intensities, indicating partial amorphization of the film with defect formation. Microstructural analysis confirmed the formation of uniform-sized nanorods for V2O5:Si, whereas isolated crystallites were formed for other types of substrates. Thermal conductivity may influence the size and shapes of V2O5 crystallite forms on different surfaces. Silicon absorbs heat more effectively than sapphire or glass, resulting in nanorod formation. A decrease in optical bandgap and electrical conduction has been observed due to increased oxygen vacancies, induced electron scattering, and trapping centres on N+ implantation. The present study thus offers the unique advantage of simultaneous reduction in optical band-gap and conductance of V2O5 thin films, which is important for optoelectronic applications.

Effect of nitrogen (N+) ion implantation on the morphological, structural, optical, and compositional properties of vanadium pentoxide (V2O5) thin films grown on glass substrates is studied. Surface morphology shows the formation of grains and the growth dynamics is governed by roughness (α) and growth (β) exponents. X-ray diffraction studies reveal that V2O5 exists in a hybrid form, with properties of both the orthorhombic and tetragonal phases. Ion implantation induces defects and strain in V2O5 thin films causing a reduction in crystalline properties and deformation in the β-phase with a corresponding change in crystallite size. Contact angle wetting properties are found to be co-related with fractal growth of the films under ion implantation. Oxygen vacancies and electron scattering/trapping centres are revealed to have increased after N+ implantation, leading to a smaller bandgap in the thin films. The benefits of decreasing the optical band-gap of V2O5 thin films for optical applications are outlined in the present work.

Surface enhanced Raman scattering (SERS) detection of rhodamine-6G on gold nanostructures (Au-NS) of various sizes under ion beam irradiation is presented. On a glass substrate, Au thin films of different thicknesses (~2, 3, and 5 nm) were deposited by thermal evaporation. Subsequent irradiation using 10 keV Ar+ at different fluences has been able to modify the size of Au-NS. Ion beam-induced sputtering and diffusion processes control the formation of Au-NS. The reduction in Au content during ion beam sputtering is confirmed by Rutherford backscattering spectroscopy, which also validates tuning the size and structures of Au-NS. The wettable characteristics of Au-NS surfaces are controlled by two competing statistical factors of sputtering and surface diffusion. A correlation between the water contact angle, rms roughness, and the detection of rhodamine-6G (R6G) by SERS is presented. The current study sheds light on the mechanism(s) of SERS chemical detection for wider metallic surfaces.

Introduction: This study focuses on the detection of rhodamine-6G using surface-enhanced Raman scattering (SERS) on gold nanostructures (AuNS) of different sizes. Ion beam irradiation has been carried out to tune the size of AuNS and investigate the underlying mechanisms of sputtering and diffusion that govern their growth. Additionally, the study established a correlation between fractal growth parameters, water contact angle, and SERS detection of R6G. The results of this study offer new insights into the mechanisms of SERS detection on roughened metallic surfaces.Methods: Thermal evaporation was used to deposit an Au thin film on a glass substrate. Subsequent 10 keV Ar+ irradiation was done on Au thin film for fluences ranging from 3×1014 to 3×1016 ions/cm2 to tune the size of AuNS. Rutherford backscattering spectroscopy (RBS) was used to confirm that the decrease in Au concentration under ion beam sputtering was responsible for the tuning in size and structure of AuNS. Fractal dimension (Df) and interface width (w) were used as statistical parameters to control the wettable characteristics of the AuNS surfaces.Results and discussion: The researchers found that the growth of AuNS was governed by ion beam induced sputtering and diffusion mechanisms. They established a correlation between fractal growth parameters, water contact angle, and SERS detection of R6G. They found that a higher surface coverage area of Au NPs with lower fractal dimensions and water contact angles favoured the SERS detection of R6G. This study provides new insights into the mechanisms of SERS detection on roughened metallic surfaces. It is found that the growth of AuNS was governed by ion beam-induced sputtering and diffusion mechanisms, and established a correlation between fractal growth parameters, water contact angle, and SERS detection of R6G. The findings of this study may have applications in the development of more sensitive and efficient SERS-based chemical sensors.

The experimentally observed effects induced by ion irradiation in AZO thin films are discussed in limited articles. Here, we report the results of ion irradiation by 300 keV Nitrogen ions. To study the structural, morphological, and optical properties of thin film, X-ray diffraction, field-emission scanning electron microscopy, and UV-visible spectroscopy were used and it was confirmed by the structural investigation that the ion irradiation resulted in changes in different calculated structural parameters. Furthermore, different dopant concentrations are examined in relation to the effects of irradiation. The polar crystal growth orientation mechanism is initiated over nonpolar crystal growth orientation, as the 2%AZO thin films are presented to ion beam irradiation. The transition in the stress of thin film after N ion irradiation is also discussed. The phenomena responsible for the morphological changes is discussed. The observed morphological changes are correlated with structural changes. The change in the colour of the thin films after irradiation is explained. The other alterations in the thin films' optical properties are also discussed. The systematics study of the irradiated thin films may be helpful for device fabrication.