Grain size tuning of nanostructured Cu2O films through vapour phase supersaturation control and their characterization for practical applications

Abstract

A strategy for creating nanostructured films is the alignment of nanoparticles into ordered superstructures as living organisms synthesize biomaterials with superior physical properties using nanoparticle building blocks. We synthesized nanostructured films of Cu2O of variable grain size by establishing the condition of supersaturation for creation of nanoparticles of copper which deposited as nanograined films and which was then oxidized. This technique has the advantage of being compatible with conventional vacuum processes for electronic device fabrication. The Cu2O film samples consisted of a secondary structure of spherical particles of almost uniform size, each particle being an agglomerate of primary nanocrystals. Fractal analysis of the AFM images of the samples is carried out for studying the aggregation mechanism. Grain size tuning of the nanostructured Cu2O films has been studied using XRD, and micro-Raman and photoluminescence spectroscopy.

CuO–ZnO nanocomposite films with efficient interfacial charge transfer characteristics for optoelectronic applications

“…All the film samples exhibited fractal dimensions greater than 2 representing motion of particles along straight trajectories until they encounter the growing aggregates and stick to their surface which is termed ballistic aggregation mechanism [36] (Table 1). The formation of nanocrystals may be through CCA, while their deposition on the substrate may be through BA [4,19,36]. The increase in the fractal dimension of the films with the increase in the Zn concentration (Table I) may be interpreted as an indication of packing of the particles with stronger interparticle contacts aiding easy charge transfer between the particles.…”

“…Copper oxide-zinc oxide (CuO-ZnO) nanocomposite films were prepared by oxidation of Cu-Zn nanocomposite films deposited on glass substrates by thermal co-evaporation of metallic Cu and Zn using a vacuum coating unit. Glass substrates were cleaned by a standard procedure [4,21,34]. Thermal co-evaporation of Cu and Zn was carried out at a pressure of 2 × 10 −4 mbar of nitrogen in the vacuum chamber.…”

“…Abraham et al [1] reported band gap tuning of visible-light active heterojunction CuO/ZnO nanocomposites for dye-sensitized solar cell applications. In the present work, copper oxide-zinc oxide (CuO-ZnO) nanocomposite films were synthesized from p-type CuO and n-type ZnO semiconductors through the oxidation of Cu-Zn nanocomposite films deposited on glass substrates for four different atom % of Zn by vacuum deposition technique at a relatively high pressure of an inert gas [4,21,34]. The nanocomposite film samples were analyzed using X-ray diffraction, atomic force microscopy, UV-vis absorption spectroscopy and micro-Raman spectroscopy.…”

A Flash‐Induced Robust Cu Electrode on Glass Substrates and Its Application for Thin‐Film μLEDs

“…[62,63] For the Cu-removed sample (red line), prominent peaks of copper (I) oxide (Cu 2 O), and glass were exhibited, indicating that a Cu 2 O layer was formed at the Cu/glass interface. [64][65][66][67] This Cu 2 O layer could be induced via re-oxidation of the Cu conductor due to the interfacial photothermal heating, [59,[68][69][70] alleviating the atomic mismatch between flash-induced Cu and glass for highly robust Cu electrode. [71][72][73][74] Figure 1d presents the cross-sectional image of flash-activated Cu on a glass substrate, as analyzed by STEM and energy dispersive X-ray spectroscopy (EDS) mapping.…”

Charge transport in grain size tuned CuO nanocrystal films

“…Nanostructured films of different semiconductors were synthesized using a variety of techniques such as thermal evaporation [23], DC and RF sputtering [24,25], pulsed laser evaporation [26], plasma evaporation [27], molecular beam epitaxy [28], chemical vapour deposition [29], sol-gel technique [30] and electrodeposition [31], and these film samples were characterized for applications such as gas sensing [32], photovoltaics [33], antireflection layers [34], photoelectrochemical water splitting and biosensors [35]. Anu and Khadar [36] synthesised nanostructured Cu 2 O films of different grain sizes by oxidizing nanostructured films of Cu deposited by controlling the supersaturation of copper vapors in the deposition chamber.The present work deals with the synthesis nanostructured films of CuO of different grain sizes, their characterization and study of electrical properties. The films were characterized using X-ray diffraction (GIXRD), high resolution electron microscopy (HRTEM), atomic forcemicroscopy (AFM), and UV-Vis spectroscopy.…”