The effect of substrate-induced strain in polycrystalline ZnO thin films on different substrate, e.g., GaN epilayer, sapphire (0001), quartz glass, Si(111)∕SiO2, and glass deposited by sol-gel process, has been investigated x-ray diffraction, scanning electron microscope, electrical resistivity, photoluminescence measurements. A strong dependence orientation, crystallite size, resistivity upon the along c axis found. results structural morphological studies indicate that relatively larger...

Graphene quantum dots (GQDs) synthesized by a direct chemical method have been used in combination with ZnO nanowires (NWs) to demonstrate their potential as solar harvesting material photovoltaic cells exhibiting an open circuit voltage of 0.8 V. The excited state interaction between the photoexcited GQDs and NWs has verified from charge-transfer process both emission spectroscopy measurements. This work implications for less expensive efficient next generation solid-state cells.

Photocapacitance spectra in undoped, metal-organic vapor-phase-epitaxy-grown GaN layers, a range of photon energies from 0.6 to 3.5 eV, reveal two main persistent features: broad increase the capacitance 2.0 2.5 and steep decrease at 1 only observed after previous light exposure above eV. A deep trap (${\mathrm{E}}_{\mathrm{v}}$ +1 eV) that captures photoelectrons valence band, being emptied with photons is proposed as origin these features. Optical-current deep-level transient spectroscopy...

A n-ZnO∕p-Si thin film heterojunction has been fabricated by a low cost sol-gel technique. The wavelength dependent photoresponse properties of the is investigated in detail studying effect light illumination on current-voltage (I-V) characteristics, photocurrent, and photocapacitance spectra at room temperature. It shows good diode characteristics with IF∕IR=3.4×103 4V reverse leakage current density 7.6×10−5Acm−2 −5V. From photocurrent spectra, it observed that visible photons are absorbed...

The anomalous photocurrent decay in aqueous solution grown ZnO nanowires (NWs) under steady ultraviolet light illumination have been investigated. growth-decay measurements using the above-band and subband gap excitation energies as-grown annealed NWs show that while a VZn-related defect complex is formed by surface adsorbed H2O molecules, faster carrier trapping O2 molecules slower recombination at defect, Zni cause supported results of spectra photoluminescence measurements. predicted...

p - Zn O ∕ n Si heterojunction is achieved by depositing Al–N codoped p-type ZnO film on n-Si low-cost sol-gel technique. The junction shows good diode characteristics with rectification ratio (IF∕IR)∼10 at 4V in the dark. photoresponse of investigated studying current-voltage under ultraviolet (370nm) and visible light (450nm) illuminations. By fitting experimental data, we have proposed current transport mechanism to be dominated recombination tunneling lower space-charge limited higher...

The authors report on the electrical and ultraviolet (UV) photoresponse properties of quasialigned ZnO nanowires (NWs)∕p-Si heterojunction grown by a low-temperature solvothermal technique. current-voltage characteristic single NW∕p-Si junction measured scanning tunneling microscope shows rectifying behavior with rectification ratio IF∕IR 33 at 5V. current transport is dominated recombination-tunneling mechanism for 0.4V<V<1.5V while space-charge-limited conduction beyond 1.5V....

ZnO nanowires (NWs) with a ZnS coating are synthesized in order to modify the surface without changing diameter of NWs. They have wurtzite at core and cubic outer layer. The NWs show sharp ultraviolet broad visible emission photoluminescence spectra. Surface modification has led change position maxima ZnO−ZnS photocarrier relaxation under steady UV illumination occurs NW arrays but is absent arrays. dark current value for both type similar, whereas photocurrent much higher surface-modified...

For halide perovskite solar cells (PSCs) to fulfill their vast potential for combining low-cost, high efficiency, and throughput production they must be scaled using a truly transformative method, such as roll-to-roll processing. Bringing this reality closer fruition, the present work demonstrates flexible with 18.1% power conversion efficiency on Willow Glass substrates. We highlight importance of transparent conductive oxide (TCO) layers device performance by studying various TCOs. While...

A p-CuO/n-ZnO thin film heterojunction is fabricated on a glass substrate by the sol–gel technique. The crystallinity of junction materials and microstructure top p-layer are examined an x-ray diffractometer (XRD) scanning electron microscope (SEM). current–voltage (I–V) characteristics p–n its temperature dependence have been investigated in air H2 ambient. Although possesses linear I–V from room (RT) to 150 °C air, at higher temperatures (200 300 °C), it shows nonlinear rectifying...

A series of Al doped ZnO (ZnO : Al) films with different concentrations have been deposited on glass substrates using the sol–gel spin coating technique and effect structural, electrical, optical photoresponse properties investigated. The XRD results show presence peaks due to reflections planes from a wurtzite type structure. surface morphology shows that grains become non-uniform smaller in size as doping level increases. For 1–2% doping, film attains highest carrier concentration about...

We have investigated the carrier relaxation process during photoconduction in quasi-one-dimensional (Q1D) ZnO nanowires (NWs) of diameters 29–36nm on different substrates using photocurrent transient measurements. Ultraviolet (UV) sensitive NWs show around three to four orders change photo-to-dark current ratio. Under steady UV illumination, photocarrier occurs through two-electron process—carrier loss due trapping by surface states and recombination at deep defect states. The results...

Single layer ZnO/polyaniline (PANI) inorganic/organic hybrid structure fabricated on glass substrate by depositing polyaniline film the sol-gel ZnO thin shows a rectifying behavior indicating formation of diode. The current transport mechanism is modeled through an energy band diagram. heterojunction sensitive to UV illumination. photo-to-dark ratio junction about 46 for −5V bias. photoresponse parameters diode are found be better than those only similar thickness. results indicate that...

Core–shell TiO2@ZnO nanorods (NRs) have been fabricated by a simple two step method: growth of ZnO NRs' array an aqueous chemical technique and then coating the NRs with solution titanium isopropoxide [Ti(OC3H7)4] followed heating to form shell. The core–shell nanocomposites are composed single-crystalline NRs, coated thin TiO2 shell layer obtained varying number coatings (one, three five times). ultraviolet (UV) emission intensity nanocomposite is largely quenched due efficient...

The effect of surface capping with poly(vinyl alcohol) (PVA) on the photocarrier relaxation aqueous chemically grown ZnO nanowires (NWs) has been investigated. decay in photocurrent during steady ultraviolet illumination due to reduced capped NWs, as evidenced from a decrease only by 12% its maximum value under for 15 min and 49% same interval time as-grown NWs. modification is confirmed FESEM, HRTEM, FTIR results. photoluminescence spectrum shows an enhanced emission defect-related NWs...

Synthesis of various nanostructured semiconductor materials and processing them for different device fabrications has been at the forefront research last two decades. In comparison to spherical nanoparticles, anisotropic e.g. nanorods, nanowires, nanodisks have widely explored obtain a better performance devices. addition, it is also well-known that nanomaterials, on doping with suitable impurities, can enhance sensitivity speed. Combining both, we report here synthesis micrometer long In2S3...

A simple route for the synthesis of a novel mesoporous zinc oxide material having wurtzite like nanocrystalline pore walls by using Schiff-base amine as template is reported, which shows very high BET surface area (456 m2 g−1) and remarkably enhanced photoconductivity photoluminescence at room temperature under visible light irradiation vis-à-vis bulk ZnO material.

Organic-inorganic hybrid diodes are very promising for solution processing, low cost, high performance optoelectronic devices. Here, we report a quality p-n heterojunction diode composed of n-type inorganic Sb2S3 and p-type organic 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) with rectification ratio ∼102 at an applied bias 1 V. On illumination visible light (470 nm, 1.82 mW/cm2), the current value in our device becomes 8 × 102 times that its dark even...

On the face of impending energy crisis, developing low-energy or even zero-energy photoelectronic devices is extremely important. A multispectral photosensitivity feature a self-powered device provides an additional powerful tool. We have developed unprecedented high performance dual wavelength ZnO@CdS/PEDOT:PSS core–shell nanorods array photodetector through simple aqueous chemical method wherein suitable band alignment between intelligent material pair, i.e. ZnO and CdS, has been utilized....