Noble metal‐doped TiO2‐based photoanode for quantum dot‐sensitized solar cells (QDSSCs) has gained significant importance in enhancing performance by increasing the light absorption and subsequently minimizing the number of recombinations due to the formation of new charge trap states. In this work, Cu ions are implanted in MXene/TiO2‐based photoanode at different fluence rates (5 × 1012, 5 × 1013, 5 × 1014, and 5 × 1015 ions cm−2). The X‐ray photoelectron spectroscopy investigations reveal the doping mechanism as at lower fluence, Cu+ ions are present, but as the fluence increased the Cu2+ ions dominate. The field emission scanning electron microscopy and energy‐dispersive X‐ray analysis are used to find the surface morphology and the elemental composition of the implanted samples. The implantation of Cu ions creates new impurity states between the energy bands, thereby enhancing light absorption capabilities and suppressing charge recombinations of the photoanode, which is confirmed by UV‐Vis and photoluminescence spectroscopy. Afterward, Cu‐implanted photoanodes are employed to fabricate QDSSC devices, and the QDSSC based on photoanode implanted at 5 × 1014 ions cm−2 fluence (Cu_3) demonstrates the highest power conversion efficiency of 3.86%, which is 34.9% higher than pristine unimplanted photoanode. This enhancement is attributed to the inhibition of the charge recombinations at the photoanode/electrolyte interface and enhanced light harvesting capability of the photoanode.

Silicon solar cells continue to dominate photovoltaic technology, holding a market value of ∼98% with an efficiency of 13-24% at the commercial level, which is limited by the recombination process and generated defects during the fabrication process. This study presents p-n junction fabrication using the ion beam technology, where boron species are implanted at a low energy of 35 keV into n-type Si (100). Doping was confirmed by X-ray photoelectron spectroscopy (XPS), which outperformed other conventional techniques (RBS and XRD) with exceptional elemental detection sensitivity. The shift in binding energy was observed to be 0.24 eV for the main peak in the silicon 2p spectra, resulting from the incorporation of boron into the silicon lattice. The local electronic environment modification was investigated by near-edge X-ray absorption fine structure (NEXAFS) spectroscopy at the O K-edge, which showed local hybridization consistent with boron incorporation and was also validated by FEFF simulations. Moreover, transport measurements exhibited diode-like I-V characteristics obtained using linear sweep voltammetry that were consistent with the Shockley diode model, indicating the formation of a p-n junction and notable suppression of the leakage current to 0.63 µA. Collectively, these findings evidence that the ion beam technology is a viable approach for the fabrication of reduced-defect structures, which are essential for the advancements of photovoltaics.

Effects of rapid thermal annealing (RTA) on 100 keV Cu implanted germanium (Ge) thin films were studied in the present report. The Cu ion implantation into Ge films was carried out at different ion fluences 5 x 1015 and 1 x 1016 ions/cm2. Subsequently, the implanted samples were subjected to RTA at 600 degrees C. XRD and Raman results illustrate the amorphization of implanted films, whereas RTA results in crystallization. Crystallite size increases from 10.5 to 11.6 nm with fluence for RTA-treated samples. The bandgap of pristine film is 0.73 eV, which gets narrowed to 0.59 eV with an increase in ion fluence. RTA leads to increase in band gap up to 1.16 eV due to recovery of lattice damage and recrystallization of films. XPS analysis of RTA-treated implanted films reveals the presence of Ge, Ge suboxides, and Cu. The broad PL emission in the visible region signifies the possible use of Ge for optoelectronic applications.

Effects of lithium (Li) ions implantation on structural, optical, and luminescent properties of MgTiO3 (MTO) thin films were investigated in the present report. The films were initially deposited at a substrate temperature of 200 degrees C, which were then annealed at 700 degrees C for crystallization. Crystalline MTO films were implanted with 30 keV Li ions at various fluences ranging from 1 x 10(14) to 1 x 10(15) ions/cm(2). The crystallinity of films decreases upon Li ions implantation at a fluence of 1 x 10(14) ions/cm(2). In contrast, a further increase in fluence to 1 x 10(15) ions/cm(2) results in an improvement in crystallinity. Annealed and implanted films show lesser transmittance than the as-deposited films. As-deposited film exhibits a bandgap of 3.79 eV, which increases to 4.28 eV upon annealing the films. Subsequently, with an increase in implantation fluence, the shrinkage in optical bandgap from 4.26 to 4.09 eV is observed. Moreover, the annealed films exhibit a refractive index of similar to 2.2 which is higher as compared to as-deposited and implanted MTO samples. X-ray photoelectron spectroscopy was carried out to investigate the surface states related to Mg, Ti, and O in the samples and to analyze the variation of defects' concentration with implantation. MTO thin films show luminescent centres in near ultraviolet and visible region. The annealing results in the enhancement of photoluminescence intensity which decreases on implantation, and a drastic quenching of intensity was observed at a fluence of 1 x 10(15) ions/cm(2). The average decay lifetime of asdeposited film is 9.1 ns. Annealing results in an increase in the average decay lifetime, while implantation leads to the reduction of average decay lifetime of MTO films.

In this study, TiO2 photoanodes are firstly incorporated with MXene at different concentrations (10 wt% - 40 wt %). Here, annealed MXene partially converts to TiO2 and provide efficient light scattering. The photoanode with optimized power conversion efficiency (PCE) is implanted by Au ion with fluence of 5 x 1012--5 x 1015 ions. cm- 2. From the XPS spectra, it has been found that formation of ionic Au is more favorable at low fluence but after exceeding the solubility limit, metallic Au dominates. Enhancement in light harvesting and reduction in charge recombination of ionic Au based photoanodes has been observed through ultraviolet-visible and photolumiscence studies respectively. The upward shifting of fermi level has been established on the basis of lower work function observed after implantation. As a result, QDSSC prepared with Au fluence of 5 x 1014 ions. cm-2 delivers 83 % PCE enhancement as compared to TiO2 based QDSSC due to combined effect of MXene incorporation and Au ion implantation.

The present study demonstrates the tuning of structural, topography, and luminescence properties of 30 keV Li -ion implanted (K,Na)NbO3 thin films synthesized using RF sputtering. The Li-ion implantation of KNN films was carried out at different ion fluences such as 3 x 10(14), 1 x 10(15), 3 x 10(15), and 1 x 10(16) ions/cm(2). The crystallinity of KNN perovskite structure gets reduced, and (001) plane shifted towards the lower angle due to implantation -induced defects. The uniform and well-shaped morphology feature evolved after ion implantation, and the correlation length gets decreased upon implantation. The improvement in transmittance of KNN films after implantation is minimal, and the optical band gap is increased with fluence. The relative PL intensity of films in the ultraviolet region increases exponentially, and the intensity of implanted sample at 1 x 10(16) ions/cm(2) is more than doubled that of the pristine sample. An increase in the carrier lifetime is evident after ion implan-tation, and a maximum of similar to 12 ns is achieved for films implanted at 1 x 10(15) ions/cm(2), and the relative contribution of the slow decay component is increased after implantation. Therefore, the physical properties of KNN thin films can be tuned systematically using Li-ion implantation and the results imply the possible use of KNN for optoelectronic applications.

Nickel implanted silicon substrate shows potential applications for the fabrication of infrared detectors, solar cells, spintronic devices as well as for the synthesis of an embedded nickel silicide layer inside Si substrates. Emerging applications of the transition metal implanted silicon structures for the fabrication of intermediate band materials motivated us to study the in-depth distribution profile of Ni ions as well as the structural changes that occur at the top of silicon substrate surface before and after annealing process. In the present work, we have carried out detailed study on the crystalline silicon substrates, implanted with Ni- ions comprising ion dose value of 5 x 1016 ions/cm2 at 100 keV implantation energy followed with the post implantation annealing at 800 & DEG;C temperature for a time duration of 2 h. The distribution profile of nickel ions inside the silicon substrate was estimated using the non-destructive simultaneous XRR-GIXRF measurements and were also compared with re-sults obtained from the RBS and SIMS measurements. The in-depth concentration profile of Ni ions inside Si substrate derived from XRR-GIXRF measurements was found to be in close agreement with that of obtained from the RBS measurements. Furthermore, our investigations clearly showed that the annealing process causes the inward and outward diffusion of the Ni atoms inside the Si substrate, thus significantly changing the in-depth concentration profile of Ni ions in the Si matrix. The XANES and EXAFS results also demonstrate the forma-tion of NiSi2 phase around Ni atoms in the implanted region of Si (100) substrate.

In the present work, the effects of ion implantation on structural, surface, optical, and photoluminescence behavior of MgTiO3 thin films have been investigated. Cobalt ions were implanted into crystalline films by varying the fluence from 3 × 1014 to 1 × 1016 ions/cm2. An intensity reduction and shift of the peak position upon implantation are attributed to amorphization and generation of strain, respectively. The root-mean-square roughness is reduced from 8.2 (pristine) to 6.4 nm upon implantation at 3 × 1014 ions/cm2 fluence and increases to 7.9 nm with a further upsurge in fluence. A non-monotonous variation in transmittance with implantation fluence is observed. The bandgap of pristine sample is ~ 4.22 eV, and the implanted samples exhibit a bandgap in the range of 4.03–3.88 eV. The surface chemical states of pristine and implanted films were analyzed using X-ray photoelectron spectroscopy. An enhancement in defects upon implantation of Co ions results in the variation of luminescence properties. A broad photoluminescence (PL) emission band extending from near UV to visible region is observed for the pristine film. The PL emission intensity is quenched upon implantation. Average decay lifetime of pristine film is observed to be 17.9 ns, which is slightly increased to 19.1 ns at 3 × 1014 ions/cm2 implantation fluence. Afterward, with a subsequent rise in implantation fluence from 1 × 1015 to 1 × 1016 ions/cm2, the average decay lifetime varied within the range of 17.2–18.9 ns. Factors responsible for different luminescent centers, structure, and morphology evolution as a consequence of Co ion implantation are reported.

Gold implanted silicon substrates are widely used for the fabrication of microelectronic devices, such as detectors for infrared imaging applications, optoelectronic devices as well as for synthesis of implanted nano-particles. The continuous down scaling of physical size of these devices motivated us to develop methodologies for the reliable depth profile studies of various implanted ion species using sensitive and non-destructive methods. In this article, we present depth profile studies for gold ions implanted in silicon substrates using simultaneous X-ray reflectivity and grazing incidence X-ray fluorescence measurements. Results obtained using the XRR-GIXRF studies were found to be fairly consistent with the experimental measurements of secondary ion mass spectrometry. Furthermore, it was noticed that energetic gold ions cause substantial amorphization of crystalline Si material in the vicinity of implanted region, which was confirmed using the GIXRD measurements. Ion implantation also induces large surface modifications and roughness effects on the top of the silicon substrate, as revealed from atomic force microscope measurements.

With the ultimate goal of commercialization, dye sensitized solar cells (DSSCs) with characteristics like low cost, high stability, fast charge transport and enhanced light harvesting are highly desirable. In order to address all these properties simultaneously; in the present work, Ag ions were doped at fluence of 10(13)-10(16) ions cm(-2) with low energy of 120 keV into TiO2 nanoparticle-nanofibers composite based photoanodes in accordance with DFT based simulations. From the XPS measurements it was confirmed that low Ag fluence resulted in substitutional Ag doping whereas interstitial doping starting to overcome in higher fluences. The substitutional Ag implanted TiO2 based photoanodes were found to exhibit higher light absorption and lower number of recombinations of photogenerated charge carriers as compared to photoanode containing interstitial Ag doped TiO2. Finally, DSSCs fabricated with substitutional Ag implanted photoanodes with fluence of 1014 ions cm(-2) showed an enhancement of 21.82% against DSSC with unimplanted photoanodes. Herein, a plausible mechanism has been proposed on the basis of DFT and experimental investigations to understand observed enhancement in photovoltaic performance.

Various optical and electrical properties of noble metal doped TiO2 nanomaterials are found to vary remarkably with change in concentration and nature of doping. In the present work, ion implantation technique has been employed for generating substitutional and interstitial Au doping in TiO2 nanoparticle-nanofiber (NP-NF) composites. Experimentally, the presence of Au at substitutional and interstitial sites of TiO2 was detected through X-ray photoelectron spectroscopy. Depth profiling of implanted Au ions confirmed the presence of Au upto 70 nm. From the theoretical simulations, it was realized that substitutional Au doping results in higher strain and lower band gap contrary to pristine TiO2 and interstitial Au doped TiO2. Finally, the Dye sensitized solar cell (DSSC) prepared with substitutional doping was found to be 23.9% more efficient than interstitial Au based DSSC owing to enhanced light harvesting, higher fermi level and minimal recombinations as corroborated from current density-voltage and electrochemical impedance spectroscopy studies.

The structural and electrical transport properties of Ge ion-implanted CoSb3 thin films were investigated. These thin films were deposited by pulsed laser deposition on the quartz substrates and 100 keV Ge ions were implanted with the ion fluences ranging from 5 × 1014, 1 × 1015 to 5 × 1015 ions/cm2. Scanning electron microscopy shows an enlargement in grains with the increase of ion fluence which is attributed to the contribution from local annealing and the creation of ion-induced defects. The electrical resistivity (ρ) measurements indicate that Ge implantation strongly influences the temperature-dependent resistivity and hence affect the charge carriers. The decrease in mobility and an increase in carrier concentration with the ion fluences lead to a decrease in electrical resistivity. The conduction mechanism study reveals that this system exhibits Mott type variable range hopping characteristics (ln ρ  $$\propto$$ 1/T1/4) in the low-temperature regime for all the samples and follow the small polaron hopping conduction mechanism, ln (ρ/T) $$\propto$$ 1/T, at high temperature up to 400 K. The room temperature Hall effect measurement and the temperature-dependent Seebeck effect reveal that these films are of n-type.

SnO2 thin films have been deposited on Si substrates using RF-magnetron sputtering and implanted by 200 keV Cu- ions with ion fluence of 2.79 x 10(16) ion/cm(2) and 4 x 10(16) ion/cm(2). Post annealing is done on the pristine and Cu- ion-implanted SnO2 thin films. Samples were characterized using the grazing-incidence X-ray diffraction (GIXRD), field-emission scanning electron microscopy (FESEM) and near-edge X-ray absorption fine structure (NEXAFS). After the annealing, amorphous to crystalline phase transition and growth of particles are seen. It is also evidenced that Cu ions do not make metallic/oxide phases up to the implantation dose of 2.79 x 10(16) ion/cm(2). Cu L-edge NEXAFS has confirmed the Cu2+ ions in the samples. The O K-edge NEXAFS spectra of annealed films have shown diminished peak intensity of O 2p to Sn 5s hybridized orbitals which signify the O vacancy formation. A pre-edge peak in the O K-edge NEXAFS of Cu implanted films has evolved and confirms the additional hybridization of unoccupied Cu d orbitals with O 2p orbitals. The improved intensity of Sn M-5,M-4-edge features is due to the enhanced crystallinity in annealed samples. Ion-solid interaction induced structural and electronic structure amendments are briefly discussed in the light of energy-loss mechanism.

Investigations on the extrinsic defects induced alteration in B-O6 octahedra, energy band-structure amendments and physical assets of ABO(3) perovskites are technologically important and require modest approaches for the defect creation and their investigations. In this study, Cu defects have been assimilated in SrVO3 films using 150 KeV Cu ion-implantation with two different ion fluences; 1.63 x 10(15) ion/cm(2) and 8.15 x 10(15) ion/cm(2). The implanted Cu ions do not make metallic/oxide clusters in SrVO3 films, as confirmed by XRD studies, but have facilitated the lattice parameter enlargement and energy band-gap narrowing by creating their defect states and V-O6 octahedra distortion. NEXAFS spectra at Cu L-edge have confirmed the Cu2+ ions in low/high Cu doses implanted SrVO3 films. Cu defects induced V-O6 octahedra distortion has manifested a diverse ligand field interaction between V 3 d and O 2p orbitals and has narrowed the; (i) energy gap of V 2p(3/2) and V 2p(1/2) transitions and (ii) energy gap between t(2g)/e(g) and the O 2p and metal (n+1)sp hybridized orbitals, leading to the band-structure alteration of SrVO3 films. Mechanistic understanding of band-structure perturbation is discussed in the light of ion-solid interaction induced defect formation in SrVO3 thin films.

One of the common complications diagnosed in Diabetes Mellitus (DM) patients is Diabetic Foot Ulcers (DFUs). It is a condition wherein the deep tissues located in the lower limb undergo inflammation and infection due to neurological abnormalities (neuropathy) and various degrees of vascular diseases (angiopathy). The concentration of L-tyrosine (Tyr) rises abruptly in DFUs, and therefore may be used as an indicator for early monitoring of the patient's condition during the onset of diabetic foot disease. Herein, we report the electrochemical enzymatic detection of Tyr using low energy ion beam modified titania nanotube (TiNT) thin films with nitrogen (N+) and gold (Au-) ions. Electrochemical Impedance Spectroscopy (EIS) analysis was performed to investigate the levels of Tyr using ion beam modified TiNT thin film electrodes. The modified electrodes exhibited excellent sensor performances with Au-TiNT and N-TiNT within the Tyr concentration range of 100 fM - 500 mu M with limit of detection (LoD)1.76 nM and 1.25 nM respectively and response time similar to 1 min. The results indicate that low energy ion beam modified TiNT/enzyme bio-electrodes can potentially be employed as a highly sensitive and portable sensor for real-time detection of L-tyrosine in wound fluids for the development of a smart bandage.

Materials with tunable optical and photoelectric properties are prerequisite for the development of highly stable, economical and efficient dye sensitized solar cells (DSSCs). In this direction, improved plasmonic DSSCs with comparatively higher light harvesting ability and reduced recombination of photo-generated charge carriers have been fabricated using low energy (120 KeV) Ag ion implanted TiO2 photoanodes at variable fluence. Herein, the origin of improved photovoltaic performance of Ag implanted DSSCs against conventional DSSC has been explained using UV-visible, photoluminescence and kelvin probe measurements. Further, the efficient interfacial charge transportation within Ag implanted DSSCs has been demonstrated through EIS measurements.

Plasmonic dye-sensitized solar cells containing metal nanoparticles suffer from stability issues due to their miscibility with liquid iodine-based electrolytes. To resolve the stability issue, herein, an ion implantation technique was explored to implant metal nanoparticles inside TiO2, which protected these nanoparticles with a thin coverage of TiO2 melt and maintained the localized surface plasmon resonance oscillations of the metal nanoparticles to efficiently enhance their light absorption and make them corrosion resistant. Herein, Au nanoparticles were implanted into the TiO2 matrix up to the penetration depth of 22 nm, and their influence on the structural and optical properties of TiO2 was studied. Moreover, plasmonic dye-sensitized solar cells were fabricated using N719 dye-loaded Au-implanted TiO2 photoanodes, and their power conversion efficiency was found to be 44.7% higher than that of the unimplanted TiO2-based dye-sensitized solar cells due to the enhanced light absorption of the dye molecules in the vicinity of the localized surface plasmon resonance of Au as well as the efficient electron charge transport at the TiO2@Au@N719/electrolyte interface.