NiO-based inverted perovskite solar cells (PSCs) have presented great potential toward low-cost, highly efficient and stable next-generation photovoltaics. However, the presence of energy-level mismatch and contact-interface defects between hole-selective contacts (HSCs) and perovskite-active layer (PAL) still limits device efficiency improvement. Here, we report a graded configuration based on both interface-cascaded structures and p-type molecule-doped composites with two-/three-dimensional formamidinium-based triple-halide perovskites.
View Article and Find Full Text PDFAdv Colloid Interface Sci
September 2020
Development of two-dimensional high-quality graphene monolayers has recently received great concern owing to their enormous applications in diverging fields including electronics, photonics, composite materials, paints and coatings, energy harvesting and storage, sensors and metrology, and biotechnology. As a result, various groups have successfully developed graphene layers on different substrates by using the chemical vapor deposition method and explored their physical properties. In this direction, we have focused on the state-of-the-art developments in the growth of graphene layers, and their functional applications in biotechnology.
View Article and Find Full Text PDFHigh concentration of dissolved phosphate ions is the main responsible factor for eutrophication of natural water bodies. Therefore, detection of phosphate ions is essential for evaluating water eutrophication. There is a need at large-scale production of real-time monitoring technology to detect phosphorus accurately.
View Article and Find Full Text PDFTo enhance the light harvesting capability of perovskite solar cells (PSCs), TiO₂ nanoparticles/nanotubes (TNNs) were incorporated into the active layer of PSCs. The TNN-containing cells showed a substantial increase in photocurrent density (), from 23.9 mA/cm² without nanotubes to 25.
View Article and Find Full Text PDFThe seed layer plays a crucial role in achieving high electrical conductivity and ensuring higher performance of devices. In this study, we report fabrication of a solution-gated field-effect transistor (FET) sensor based on zinc oxide nanorods (ZnO NRs) modified iron oxide nanoparticles (α-FeO NPs) grown on a highly conductive sandwich-like seed layer (ZnO seed layer/Ag nanowires/ZnO seed layer). The sandwich-like seed layer and ZnO NRs modification with α-FeO NPs provide excellent conductivity and prevent possible ZnO NRs surface damage from low pH enzyme immobilization, respectively.
View Article and Find Full Text PDFThere are considerable interests to detect and monitor the abnormal level of minerals in water for avoiding/preventing any toxic effects after consumption. Herein, we report the fabrication of solution-gated field-effect-transistor (FET) based potassium sensor using iron oxide nanoparticles (FeO NPs) modified directly grown zinc oxide nanorods (ZnO NRs). The FeO NPs modification of ZnO NRs provided stability to nanorods surface and improved surface area for valinomycin immobilization.
View Article and Find Full Text PDFThere are increasing demands of more sensitive sensors for monitoring potential hazards in real water that may cause serious problems to human health. Herein, we report the development of a non-enzymatic nitrite sensor using nanocomposite of reduced graphene oxide decorated with silver nanoparticle (Ag-rGO). First, Ag-rGO nanocomposite was synthesized using a facile and cost-effective microwave-assisted approach.
View Article and Find Full Text PDFJ Colloid Interface Sci
April 2018
Potassium is an important body mineral that control the cellular and electrical functions in the body. The potassium ion concentration change in human serum causes the risk of acute cardiac arrhythmia. Hence, it is important to monitor the potassium level in drinking water/food to control the intake and prevent its effect.
View Article and Find Full Text PDFJ Colloid Interface Sci
February 2018
The progress in developing the electrochemical sensors for biomolecule detection requires a facile device fabrication method. Herein, we report printing of silver (Ag) precursor and copper oxide nanoparticles (CuO NPs) inks by nozzle-jet technique to fabricate non-enzymatic glucose biosensor on flexible polyethylene terephthalate (PET) substrate. The fully printed CuO NPs/Ag/PET electrodes were characterized using electrochemical techniques for non-enzymatic biosensing of glucose.
View Article and Find Full Text PDFHerein, we fabricated nonenzymatic flexible field-effect transistor (f-FET) based glucose sensor using nickel oxide quantum dots (NiO QDs) modified zinc oxide nanorods (ZnO NRs). The ZnO NRs surfaces were coated with NiO QDs using radio frequency (RF) magnetron sputtering to enhance the electrocatalytic feature and the surface area of ZnO NRs. Under physiological conditions (pH 7.
View Article and Find Full Text PDFNanowires (NWs)-based field-effect transistors (FETs) have attracted considerable interest to develop innovative biosensors using NWs of different materials (i.e. semiconductors, polymers, etc.
View Article and Find Full Text PDFJ Colloid Interface Sci
November 2017
Printable electronics is a subject of great interest for low-cost, facile and environmentally-friendly large scale device production. But, it still remains challenging for printable biosensor development. Herein, we present the fabrication of nozzle-jet printed flexible field-effect transistor (FET) glucose biosensor.
View Article and Find Full Text PDFThere is a major challenge to attach nanostructures on to the electrode surface while retaining their engineered morphology, high surface area, physiochemical features for promising sensing applications. In this study, we have grown vertically-aligned ZnO nanorods (NRs) on fluorine doped tin oxide (FTO) electrodes and decorated with CuO to achieve high-performance non-enzymatic glucose sensor. This unique CuO-ZnO NRs hybrid provides large surface area and an easy substrate penetrable structure facilitating enhanced electrochemical features towards glucose oxidation.
View Article and Find Full Text PDFThis study demonstrates a highly stable, selective and sensitive uric acid (UA) biosensor based on high aspect ratio zinc oxide nanorods (ZNRs) vertical grown on electrode surface via a simple one-step low temperature solution route. Uricase enzyme was immobilized on the ZNRs followed by Nafion covering to fabricate UA sensing electrodes (Nafion/Uricase-ZNRs/Ag). The fabricated electrodes showed enhanced performance with attractive analytical response, such as a high sensitivity of 239.
View Article and Find Full Text PDFJ Colloid Interface Sci
July 2017
A promising field-effect transistor (FET) biosensor has been fabricated based on pyruvate oxidase (PyO) functionalized ZnO nanorods (ZnO NRs) array grown on seeded SiO/Si substrate. The direct and vertically grown ZnO NRs on the seeded SiO/Si substrate offers high surface area for enhanced PyO immobilization, which further helps to detect phosphate with higher specificity. Under optimum conditions, the fabricated FET biosensor provided a convenient method for phosphate detection with high sensitivity (80.
View Article and Find Full Text PDFHerein, pre-seeded fluorine doped tin oxide (FTO) glass substrates were used as an electrode for zinc oxide nanorods (ZnO NRs) growth by a low-temperature solution route in order to fabricate binder-free high-sensitive chemical sensor. The vertically-grown ZnO NRs exhibited a more favorable active morphology and improved sensing properties for p-nitroaniline (pNA) detection. On investigation with different concentrations of pNA, the ZnO NRs/FTO electrode showed an excellent sensitivity (10.
View Article and Find Full Text PDFHerein, we report a binder-free, stable, and high-performance hydrazine chemical sensor based on vertically aligned zinc oxide nanorods (ZnO NRs), grown on silver (Ag) electrode via low-temperature solution route. The morphological characterizations showed that the NRs were grown vertically in high density and possess good crystallinity. The as-fabricated hydrazine chemical sensors showed an excellent sensitivity of 105.
View Article and Find Full Text PDFJ Photochem Photobiol B
August 2016
Porous zinc oxide (ZnO) spheres were synthesized by facile low temperature solution route. The as-synthesized porous ZnO spheres were characterized in detail in terms of their morphological, structural, optical and photocatalytic properties using field-emission scanning electron microscopy (FESEM, equipped with energy dispersive spectroscopy (EDS)), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffractometer (XRD), UV-visible spectroscopy and Raman-scattering measurements. Nitrogen adsorption-desorption analysis was performed to determine pore size distribution from the adsorption isotherm curves using the Barrett-Joyner-Halenda (BJH) method.
View Article and Find Full Text PDFACS Appl Mater Interfaces
June 2016
Intelligently designed surface nanoarchitecture provides defined control over the behavior of cells and biomolecules at the solid-liquid interface. In this study, CuO quantum dots (quanta-CuO; ∼3-5 nm) were synthesized by a simple, low-temperature solution process and further formulated as paint to construct quanta-CuO thin film on glass. Surface morphological characterizations of the as-coated glass surface reveal a uniform film thickness (∼120 ± 10 nm) with homogeneous distribution of quanta-CuO.
View Article and Find Full Text PDFWe report a novel straightforward approach for simultaneous and highly-selective detection of multi-analytes (i.e. glucose, cholesterol and urea) using an integrated field-effect transistor (i-FET) array biosensor without any interference in each sensor response.
View Article and Find Full Text PDFHerein, we demonstrate the fabrication of a robust enzymeless glucose sensor based on CuO nanoseeds (CNSs) synthesized at low-temperature. The as-fabricated sensor exhibited excellent electrocatalytic ability in a wide-linear range and was further employed for the glucose concentration determined in freshly drawn mice whole blood and serum samples.
View Article and Find Full Text PDFThe development of stimuli-responsive nanocarriers is becoming important in chemotherapy. Liposomes, with an appropriate triggering mechanism, can efficiently deliver their encapsulated cargo in a controlled manner. We explored the use of acid-sensitive zinc oxide nanoparticles (ZNPs) as modulators of the responsive properties of liposomes.
View Article and Find Full Text PDFWe report the growth of high-quality GaN layer on single-walled carbon nanotubes (SWCNTs) and graphene hybrid structure (CGH) as intermediate layer between GaN and sapphire substrate by metal-organic chemical vapor deposition (MOCVD) and fabrication of light emitting diodes (LEDs) using them. The SWCNTs on graphene act as nucleation seeds, resulting in the formation of kink bonds along SWCNTs with the basal plane of the substrate. In the x-ray diffraction, Raman and photoluminescence spectra, high crystalline quality of GaN layer grown on CGH/sapphire was observed due to the reduced threading dislocation and efficient relaxation of residual compressive strain caused by lateral overgrowth process.
View Article and Find Full Text PDFZnO platforms were evaluated for designing a high-performance anticancer drug (daunorubicin) carrier. Hollow structured ZnO, compared with nanorods, acts as a multi-purpose entity by serving as smart carriers and exhibiting synergetic photodynamic cytotoxic effects, which are ascribed to their high-specific surface area, hollow interior, pH-responsiveness and inherent photodynamism.
View Article and Find Full Text PDFLateral growth of one-dimensional nanostructures is crucial for high performance field-effect transistors (FETs) which can drive a high on-current that is proportional to the number of nanorods (NRs) aligned between electrodes. Hence, it is strongly required to laterally and directly grow a large number of NRs between electrodes. For the first time, we propose a polyhedral-type FET (PH-FET) based on laterally-grown ZnO NRs, which includes circle, square and triangle configurations.
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