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The dynamics and control of charge transfer between optoelectronically interesting and size-tunable halide perovskite quantum dots and other juxtaposed functional electronic materials are important issues for the emergent device interest involving such a family of materials in heterostructure configurations. Herein, we have grown bimetallic Au–Ag thin films on glass by pulsed laser deposition at room temperature, which bear nanoparticulate character, and the corresponding optical absorption spectra reveal the expected surface plasmon resonance signature(s). Subsequently, spin-coated CsPbBr3 nanoparticle films onto the bimetallic Au–Ag films exhibit surface-enhanced Raman scattering as well as strong photoluminescence quenching, the latter reflecting highly efficient transfer of photo-generated carriers across the CsPbBr3/Au–Ag interface. Surprisingly, when an ultrathin MgO (insulating) layer of optimum thickness is introduced between the CsPbBr3 and Au–Ag films, the charge transfer is further facilitated with the average lifetime of carriers becoming even shorter. By changing the thickness of the thin MgO layer, the carrier lifetime can in fact be tuned; with the charge transfer getting fully blocked for thick enough MgO layers, as expected. Our study thus throws light on the charge-carrier dynamics in halide perovskites, which is of importance to emergent optoelectronic applications.

Porphyrin compounds have gained significant attention and proposed technical applications, including gas sensors and optoelectronic systems. One of them is 2,7,12,17-tetra-tert-butyl-5,10,15,20-tetraaza-21H,23H-porphyrin (TTBTP) which is a highly structured organic semiconductor in thin films. Thin TTBTP films have been produced using the vacuum thermal evaporation technique. Testing for X-ray diffraction reveals that TTBTP films are nanostructured, with an average grain size of 56 nm. The conduct against frequency (40 Hz–5 MHz) and temperature (303–373 K) of the complex dielectric constant was investigated. Further, the relationship between the complex electric module and the frequency at different temperature values has been discussed. The relaxation activation energy has been calculated as 0.156 eV, and the relaxation process is defined as non-Debye for TTBTP film. Jonscher's formalism clarified the action of conductivity in the higher frequency range. Within the TTBTP film, the transfer of carrier charge was controlled by the corresponding correlated barrier hopping model. Moreover, the obtained rise of frequency indicates a decrease in the activation energy values of AC conduction.

A bimetallic (Ag/Au) nanoslit film is reported on surface plasmon (SP) generation and refractive index (RI) sensitivity. These were compared to gold devices in transmission surface plasmon resonance (tSPR). The bimetallic films have a primary resonant peak that shifts with periodicity and correlates well with Finite-Difference Time-Domain (FDTD) simulation studies. The SPR of bimetallic nanoslit structures is analyzed via a semi-analytical model. The model enables decomposition and quantitative analysis of SP generation at the aperture under plane-wave illumination. The nanostructured, metallic, thin films provide flexibility to integrate with microfluidics, allowing for simplified instrumentation and alignment. Calculation and experimentation demonstrate that bimetallic films afford an increase in RI sensitivity due to the addition of silver along with the biocompatibility of gold. The Ag/Au films were found to be non-diffusing, long-term stable (over several months), and provided an increase in sensitivity (about 53/RIU) over gold equivalents.

The continuous effort for transitioning pulsed laser deposition (PLD) technique from an experimental tool into an industrial one can be sustained by the use of complex tools for in situ real-time monitoring of the deposition process. Langmuir Probe (LP) and optical emission spectroscopy (OES) measurements were used for plasma monitoring during PLD of silver films under various Ar pressure conditions. The LP measurements revealed a multi-structured distribution of the ions, which was strongly influenced by the increase of Ar pressure. The generation of highly energetic ions with the addition of Ar and the degree of Ar gas ionization was confirmed by OES measurements. A perturbative effect was seen under pressures higher than 10 Pa, where the presence of high electronic charges leads to an unstable behavior of plasma in the vicinity of the LP. The effect of these complex dynamics on the structure and quality of the deposited thin film was investigated revealing a strong correlation between the electronic distribution in plasma and thin film thickness profile.

Many studies on the Photoconductivity of ZnO have been performed with an indication of reliable optical application due to fast photo response. This paper reports study of intensity dependent photoconductivity in ZnO nanostructured thin film with a thickness of 800 nm. ZnO nanostructured thin film on ultra clean glass substrate has been deposited using sol-gel spin coating technique. Conductivity at various illumination intensity has been measured using two probe method and found that photoconductivity increases by increasing illumination intensity. Photoconductivity can be utilized in the devices fabrication which are based on the decrease in the resistance of certain materials when they are exposed visible radiation. Photosensitivity and persistent photo conductivity also found to be increasing with illumination intensity. Photo sensitivity enhancement in Nanostructured ZnO is expected due to its large surface to volume ratio which is fundamentally more suitable for optical devices application. Persistent photoconductivity in the ZnO nanostructure thin film can be utilize in memory device applications.

TiO2 films on SiO2 pre-coated glass substrate were prepared by sol–gel dip-coating method. The effects of solvent type in the sol on crystalline structure, microstructure, optical properties, photocatalytic activity and hydrophilicity of the films were investigated. X-ray diffraction, scanning electron microscopy, atomic force microscopy, UV–Vis spectrophotometer and contact angle measurement were used for investigation of film properties. Isopropanol (i-PrOH), ethanol (EtOH) and methanol (MtOH) were used as the solvents. It was shown that the type of solvent affects TiO2 thin film properties. The layers of TiO2 on SiO2 pre-coated substrate after heat treatment were transparent in color and uniform in thickness and color. All TiO2 films prepared in this work were of the anatase phase and were orientated along the (101) plane. It was found that methanol had best effects on the photocatalytic and super-hydrophilic properties of TiO2 films. It might be due to smaller particle size of the crystallites in the sample derived from sol containing methanol.

This paper describes the selective electrochemical determination of paracetamol (PA) in the presence of important interferent, ascorbic acid (AA) using an ultrathin electropolymerized film of 5-amino-1,3,4-thiadiazole-2-thiol (p-ATT) modified glassy carbon (GC) electrode in 0.20 M phosphate buffer solution (pH 7.20). Bare GC electrode failed to resolve the voltammetric signals of AA and PA in a mixture. On the other hand, the p-ATT modified electrode not only separated the voltammetric signals of AA and PA but also enhanced their peak currents. We achieved the lowest detection lit-nit of 0.34 nM (S/N=3) for PA at p-ATT modified electrode.

ZnO nanostructured film is synthesized by solution combustion technique. X-ray diffraction (XRD) studies show that preferred orientation is along (101) confirming the hexagonal wurtzite phase and no secondary phase is observed. The rietveld refinement of the XRD data was used to calculate different lattice parameters. I-V characterization of ZnO film shows non linear behavior. These ZnO films are photosensitive, may be due to defect states. This property of these films can be utilized in optoelectronic applications.

A sol–gel method was employed to prepare TiO2 particles in the powder form and on a flat quartz (SiO2) support. Calcination at progressively higher temperatures caused morphological and structural changes, which were followed by XRD, UV-Vis spectroscopy, AFM, and SEM microscopy. In particular, it was found that annealing at 500 °C leads to the formation of the anatase phase for both TiO2 on SiO2 and TiO2 in the powder form (self-supported). However, after annealing at 800 °C the TiO2 particles on SiO2 remained in the anatase form, whereas the anatase phase of self-supported TiO2 particles was easily converted into the rutile form. TiO2 particles on SiO2 remained as individual crystallites even at 800 °C despite the growth of their size, whereas annealing TiO2 powders at 500 and 800 °C led to bigger crystallites with their eventual sintering to very big particles of micrometer size. Examination of the photocatalytic activity of TiO2 on SiO2 and TiO2 in the powder form in the reaction of acetaldehyde oxidation demonstrated the TiO2 on SiO2 superiority with quantum yields significantly higher than that of TiO2 powder.

We have developed the separated pulsed laser deposition (SPLD) technique to prepare high quality ZnO based films exhibiting uniform and droplet-free properties. This SPLD consists of an ablation chamber and a deposition chamber which can be independently evacuated under different ambient gases. The gas species and the pressures in both chambers can be arbitrarily chosen for the specific deposition such as nanostructured films and nanoparticles. The ablation chamber is a stainless steel globe and the deposition chamber is a quartz tube connected to a metallic conic wall with an orifice. We used a KrF excimer laser with λ = 248 nm and 25 ns pulse duration. The different gas conditions in two chambers allow us to realize optimal control of the plasma plume, the gas phase reaction and the film growth by applying the bias voltage between the conic wall and the substrate under the magnetic field. We can expect that at appropriate pressures the electric and magnetic field motion ( E × B azimuthal drift velocity) gives significant influences on film growth. We have deposited ZnO thin films at various pressures of ablation chamber (Pab) and deposition chamber (Pd). The deposition conditions used here were laser fluence of 3 J/cm 2 , laser shot number of 30,000, Pab of 0.67–2.67 Pa (O 2 or Ar), Pd of 0.399–2.67 Pa (O 2 ), and substrate temperature of 400 °C. Particle-free and uniform ZnO films were obtained at Pab of 0.67 Pa (Ar) and Pd of 1.33 Pa (O 2 ). The ZnO film showed high preferential orientation of (002) plane, optical band gap of 2.7 eV, grain size of 42 nm and surface roughness of 1.2 nm.

An approach to directly make controlled nanostructured films in situ with physical vapor thin film deposition is presented. Co films were formed into lines with 3.2±0.8 nm thickness and were regularly spaced 550±20 nm apart on a Si(100) surface. The line pattern results during pulsed laser deposition of Co simultaneous with two-beam laser interference irradiation of the Si surface. Preliminary results indicate that preferential evaporation is not the primary mechanism. This patterning is likely due to anisotropic diffusion modified growth of Co under thermal gradients. This one step patterning process, without need of any pre- or post-patterning of the substrate or film, is promising as an economical and simple nanostructured film fabrication approach.

ZnO nanostructured films were deposited at room temperature on glass substrates and cotton fabrics by activated reactive evaporation in a single step without using metal catalyst or templates. Morphological observation has shown that the nanostructured film contains seaurchin-like structures, and this seaurchin containing large number of randomly grown ZnO nanoneedles. Microstructural analysis revealed the single crystalline nature of the grown nanoneedles and their growth direction was indentified to be along [0002]. PL spectrum of nanostructured films has shown a relatively weak near-band-edge emission peak at 380 nm, and a significant broad peak at 557 nm due to the oxygen vacancy-related emission. ZnO nanostructured films grown on glass substrates and cotton fabrics have shown good photocatalytic activity against rhodamine B.

The chevronic silver film with thickness 230±5 nm is fabricated using bideposition technique. The real part of the equivalent refractive index and the equivalent permeability of the film are negative at the wavelength 639 nm.

We report the growth and low-temperature photoluminescent characteristics of well-aligned Ni-doped ZnO nanoneedles and V-doped ZnO nanostructured thin film grown by a modified pulsed laser deposition technique. Low-temperature photoluminescence spectra of the as-grown films show the presence of free excitonic as well as bound excitonic transitions, whose relative intensity changes with increasing temperature. Ni-doped ZnO films show a characteristic fine structure in the visible range (2.6?2.9?meV) attributed to either exciton?polariton longitudinal?transverse splitting or the splitting caused by electron?hole exchange interaction. The excitonic and visible region emission can be clearly seen as can the phonon replicas produced from longitudinal optical phonons. Different possible attributions of the various peaks in the emission band at low temperature have been discussed. The as-grown nanostructures of Ni- and V-doped ZnO thin films also clearly show the effect of doping on the microstructure of ZnO.

Substitution of a polyelectrolyte for silica during formation of surfactant-templated films produces similar nano- and macroscale structures confirming that silica acts as a polyelectrolyte during thin film self-assembly.

The immobilization of albumin and lysozyme by spontaneous adsorption on ZnO films, deposited by metal-organic chemical vapour deposition (MOCVD), has been investigated. Quartz crystal microbalance with dissipation monitoring and X-ray photoelectron spectroscopy analyses show that, at physiological pH, the two proteins exhibit different adsorption behaviours, namely albumin irreversibly adsorbs up to coverage of a half of monolayer, while lysozyme does not. Indeed, the high isoelectric point (IEP) of ZnO favors immobilization of biomolecules with lower IEP, assisted by electrostatic attraction in the proper pH range. This selective protein adsorption behaviour results very promising for ZnO nanoplatforms, consisting of hexagonally patterned ZnO nanoring arrays and SiO2 areas, obtained by colloidal template-catalyst assisted MOCVD.

About 3 μm thick tungsten trioxide film electrodes consisting of partly sintered, 40-80 nm in diameter, particles deposited on conducting glass substrates exhibit high photon-to-current conversion efficiencies for the photooxidation of water, exceeding 70% at 400 nm. This is facilitated by a ca. 40% film porosity resulting in high contact area with the electrolyte. It is shown that the activity of the WO 3 electrodes towards photooxidation of water is enhanced by addition of even small amounts of halide (Cl - , Br - ) ions to the acidic electrolyte. Photoelectrolysis experiments performed either in acidic electrolytes containing chloride or bromide anions or in a 0.5 M NaCl solution, under simulated 1.5 AM solar illumination, demonstrated long term stability of the photocurrents. Oxygen remains the main product of the photoanodic reaction even in a 0.5 M NaCl solution, a composition close to the sea water, with chlorine accounting for ca. 20% of current efficiency.

A three-dimensional flower-like ZnO nanostructured film decorated with the thin porous ‘petals’ is synthesized using an inexpensive sol–gel drop-casting method, and the NO2 detection characteristics of the nanostructured film are studied. The gas-sensing study shows higher sensitivity with selectivity toward NO2 gas, exhibiting good reproducibility and stability. The as-synthesized nanostructured 3D flower-like ZnO film shows excellent NO2 sensing performance, with a maximum gas response of 23.3 for 100 ppm NO2 gas at an operating temperature of 180 °C. A detailed gas-sensing study reveals that the enormous porous petals with various inter-connected pores fused on the flower-like ZnO nanostructure improve the adsorption of gas molecules; consequently, the synthesized ZnO nanostructure exhibits a superior level of NO2 gas-sensing activity. This study provides a promising path towards the development of a highly sensitive NO2 gas sensor and an easy way to fabricate the 3D morphology decorated with exceedingly porous ‘petals’.

Hafnium dioxide (HfO2) is attracting attention for bio-related applications due to its good cytocompatibility, high density, and resistance to corrosion and mechanical damage. Here we synthesize two types of hafnium-oxide thin films on substrates via self-organized electrochemical anodization: (1) an array of hierarchically structured nanorods anchored to a thin oxide layer and (2) a microscopically flat oxide film. The nanostructured film is composed of a unique mixture of HfO2, suboxide Hf2O3, and oxide-hydroxide compound HfO2·nH2O whereas the flat film is mainly HfO2. In vitro interaction of the two films with MG-63 osteoblast-like cells and Gram-negative E. coli bacteria is studied for the first time to assess the potential of the films for biomedical application. Both films reveal good cytocompatibility and affinity for proteins, represented by fibronectin and especially albumin, which is absorbed in a nine times larger amount. The morphology and specific surface chemistry of the nanostructured film cause a two-fold enhanced antibacterial effect, better cell attachment, significantly improved proliferation of cells, five-fold rise in the cellular Young's modulus, slightly stronger production of reactive oxygen species, and formation of cell clusters. Compared with the flat film, the nanostructured one features the weakening of AFM-measured adhesion force at the cell/surface interface, probably caused by partially lifting the nanorods from the substrate due to the strong contact with cells. The present findings deepen the understanding of biological processes at the living cell/metal-oxide interface, underlying the role of surface chemistry and the impact of nanostructuring at the nanoscale.

Nanostructured CuO thin film was deposited on glass substrate using a radio-frequency magnetron sputtering technique. The topological measurements performed by AFM showed the polycrystalline structure of deposited film and the size of CuO nanocrystallites was analyzed. The linear optical absorption of the CuO nanostructured film was studied by UV-Vis spectroscopy and the band-gap energies of indirect and direct transitions were obtained. By performing Z-scan measurements using a picosecond laser the nonlinear absorption coefficient and imaginary parts of the third-order nonlinear susceptibility of the CuO nanostructured film were determined. Nanostructured CuO film exhibited large optical nonlinearity due to saturable absorption caused by electrons filling of excited bands and/or depletion of ground band.

We present a form of hematite (α-Fe 2 O 3 ) nanostructured architecture suitable for photoelectrochemical water oxidation that is easily synthesized by a pulsed laser deposition (PLD) method. The architecture is a column-like porous nanostructure consisting of nanoparticles 30–50 nm in size with open channels of pores between the columns. This nanostructured film is generated by controlling the kinetic energy of the ablated species during the pulsed laser deposition process. In a comparison with the nanostructured film, hematite thin film was also synthesized by PLD. All of the developed films were successfully doped with 1.0 at% of titanium. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and UV–visible spectroscopy were used to characterize the films. To fabricate the photoelectrochemical (PEC) cell, Ti-doped hematite films were used as the working electrode, Ag/AgCl as the reference electrode, platinum wire as the counter electrode and an aqueous solution of 1 M NaOH as the electrolyte. The photovoltaic characteristics of all cells were investigated under AM 1.5G sunlight illumination of 100 mW/cm 2 . The photocurrent density was enhanced by approximately 220% using nanostructured film at 0.7 V versus Ag/AgCl compared to hematite thin film, and the highest photocurrent density of 2.1 mA/cm 2 at 0.7 V/Ag/AgCl was obtained from the 1.0 at% Ti-doped hematite nanostructured film. The enhanced photocurrent density is attributed to its effective charge collection due to its unique column-like architecture with a large surface area.

In the present work, ZnO nanostructured thin films were grown on glass substrates by a simple successive ionic layer absorption and reaction method (SILAR) process at relatively low temperature for its self cleaning application. X-ray diffraction, scanning electron microscopy and Photoluminescence (PL) spectra were used to characterize the prepared ZnO nanostructured film. XRD pattern clearly reviles that the grown ZnO nanostructure film reflect (002) orientation with c-direction. SEM image clearly shows the surface morphology with cluster of spindle and flower-like nanostructured with diameter various around 350 nm. Photoluminescence (PL) spectra of ZnO nanostructures film exhibit a UV emission around 385nm and visible emission in the range around 420–500 nm. Good water repellent behavior were observed for ZnO nanostructured film without any surface modification.

Nanometer-scale thin film of Ni supported on glassy carbon (nm-Ni/GC) was prepared by electrochemical deposition through cyclic voltammetry (CV). The properties of nm-Ni/GC were studied by electrochemicalin situ FTIR reflection spectroscopy using CO adsorption as probe reaction. It has revealed that the nm-Ni/GC exhibits abnormal infrared effects (AIREs). The study has extended the investigation of the AIREs that we have discovered initially on nanostructured film materials of platinum group metals and alloys to nanostructured film materials of iron group metals.

Air pollution is a big concern as it causes harm to human health as well as environment. NO2 can cause several respiratory diseases even in low concentration and therefore an efficient sensor for detecting NO2 at room temperature has become one of the priorities of the scientific community. Although two dimensional (2D) materials (MoS2 etc.) have shown potential for NO2 sensing at lower temperatures, but these have poor desorption kinetics. However, these limitations posed by slow desorption can be overcome, if a material in the form of a p-n junction can be suitably employed. In this work, ~150 nm thick SnSe2 thin film has been deposited by thermally evaporating in-house made SnSe2 powder. The film has been studied for its morphological, structural and gas sensing applications. The morphology of the film showed that the film consists of interconnected nanostructures. Detailed Raman studies further revealed that SnSe2 film had 31% SnSe. The SnSe-SnSe2 nanostructured sensor showed a response of ~112% towards 5 ppm NO2 at room temperature (30 °C). The response and recovery times were ~15 seconds and 10 seconds, respectively. Limit of detection for NO2 was in sub-parts per million (sub-ppm) range. The device demonstrated a better response towards NO2 compared to NH3, CH4, and H2. The mechanism of room temperature fast response, recovery and selective detection of NO2 independent of humidity conditions has been discussed based on physisorption, charge transfer, and formation of SnSe-SnSe2 (p-n) nano-junctions. Depositing a nanostructured film consisting of nano-junctions using an industrially viable thermal evaporation technique for sensing a very low concentration of NO2 is the novelty of this work.

In the thin-film formation process, it is generally accepted that thin film growth occurs via a reaction between the surface and atoms and/or molecules in the gas phase. The theory of charged clusters proposes instead that a thin film is a self-assembly of charged clusters that nucleate in the gas phase. It was demonstrated that similar-sized anatase clusters have quite different deposition behaviors depending on the RF power in the reaction chamber. At 180 W a highly crystalline nanostructured film was produced. However, at 90 W, a nanopowder was deposited instead. This can be explained by the theory of charged clusters, in that the clusters become charged at higher RF power, i.e. the charging efficiency of clusters increases with increasing RF power. Lower power (90 W) did not efficiently charge the anatase clusters. Cluster charging at 180 W resulted in Coulombic repulsion, which prevented the agglomeration observed at 90 W. The self-assembly characteristics of charged clusters is highlighted by the formation of a nanostructured film.

One step electrodeposition method has been used to realize highly porous ZnO pin hole (ZP) and ZnO rosette sheets (ZS) nanostructure based photo-anodes for efficient photoelectrochemical (PEC) splitting of water. Electrodeposited ZP and ZS based photo-anodes exhibit enhanced photocurrent density of 0.62 mA/cm2 and 0.76 mA/cm2 respectively (at a bias of 0.75 V). Further on hydrothermal amination (A), these electrodeposited ZP and ZS (A-ZP and A-ZS) nanostructure based photo-anodes had shown enhanced photocurrent density of 1.02 mA/cm2 and 1.27 mA/cm2, respectively. Surface morphology, evolution and elemental study were done using FESEM and EDX. Raman spectra of aminated photo-anodes have peaks at ∼270 cm−1 and ∼511 cm−1 related to stretching vibration mode between Zn N and Zn O. The peaks at wave number ∼558 cm−1 and ∼571 cm−1 is due to formation of Zn C bonds and because of complex defects respectively. ZnO exhibits low PEC activity, but on nano-structuring in the form of ZP and ZS improves its light absorption capacity. Hydrothermal amination red shifts (∼25 nm) the absorption band at ∼ 425 nm. The N and C act as electron reservoirs in A-ZP and A-ZS photo-anodes and efficiently separate the photo-generated electron/hole pairs and restrain charge recombination to generate photo-reactive sites. Electrochemical impedance spectroscopy (EIS) revealed that A-ZP and A-ZS had low charge transfer resistance compared to their bare counterparts. This lead to considerably improved PEC performance. An unprecedented increase in IPCE values in A-ZP and A-ZS can be assigned to the decrease in band gap and thereby significant enhancement in photocurrent density. These result in to proper charge segregation and improved charge transportation. The maximum value of IPCE is 9.6% for A-ZS sample and it is also clear that ZP and ZS nanostructured film have higher IPCE values at ∼400 nm than traditional ZnO thin film. A-ZP and A-ZS based photo-anodes have exhibited enhanced PEC performance as evident from IPCE measurements and thus can be a prospective candidate for PEC and optoelectronic applications.

Fabrication of metal nanoclusters via gas phase synthesis method and their deposition on a solid surface has numerous importances as far as the application is concerned. The size of the deposited nanostructure can influence various properties of a thin film which led us to carry out the study of morphological aspects of the films that have been prepared by the mass- or size-selected silver nanoclusters on Si substrates. The Ag-nanoclusters films are produced by using a gas aggregation type magnetron-based nanocluster source and the size-selection is done by a Quadrupole Mass Filter (QMF) attached with the cluster source. The film deposition is carried out at varied cluster beam current for constant deposition time for the cluster size of about 4 nm diameter. The morphology of the films is investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). From the observations, it is found that initially the nanostructured film is mono-dispersed for a lower cluster ion current while for higher ion current mound-like structures appear. The effects of surface diffusion and agglomerations of deposited clusters are discussed for the formation of mound-like structures. Structural and composition studies show the elemental purity of the films under investigation.

Thin films and Surface Enhanced Raman spectroscopy have a strong bonding towards development of Sensors. From last 4 decades SERS has been used as effective tool for detection of toxic dyes, in food industry and agriculture world. To minimize the cost and fabrication over large surface is the most challenging task in substrate fabrication. In the present work an attempt has been made towards dual coatings, which could act as an effective SERS Substrates. An effective and facile approach of low cost bi-metallic Nanostructured film has been fabricated using thermal evaporation. Using the standard characterization techniques such as FE-SEM and XRD, the obtained films were Rhodamine 6G was used as an analyte for the SERS studies. The detection of R6G was up to 10− 10mol l− 1solution.The present bi-metallic coating can be serves as an excellent SERS active surface and provides a versatile pathway to fabricate anisotropic nanostructure on a glass film.

The control of the spontaneous formation of nanostructures at the surface of thin films is of strong interest in many different fields, from catalysts to microelectronics, because surface and interfacial properties may be substantially enhanced. Here, we analyze the formation of nickel oxide nanocuboids on top of La2Ni1−xMn1+xO6 double perovskite ferromagnetic thin films, epitaxially grown on SrTiO3 (001) substrates by radio-frequency (RF) magnetron sputtering. We show that, by annealing the films at high temperature under high oxygen partial pressure, the spontaneous segregation of nanocuboids is enhanced. The evolution of the structural and magnetic properties of the films is studied as a function of the annealing treatments at different temperatures. It is shown that the formation of NiOx nanocuboids leads to a nanostructured film surface with regions of locally different electrical transport characteristics., We acknowledge financial support from the Spanish Ministry of Science, Innovation and Universities through Severo Ochoa Program (CEX2019-000917-S) and RTI2018-099960-B-I00 (SPINCURIOX) and funding from the European Union’s Horizon 2020 research and innovation program under the Marie-Sklodowska-Curie grant agreement No. 645658 (DAFNEOX Project) and FEDER Program. Z.K. acknowledge the support of the Serbian Ministry of Education, Science and Technological Development (III45018). This work has been performed in the framework of the PhD program of the Universitat Autonoma de Barcelona (UAB).