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Adsorption effect of NO2 on ZnO (100 nm) nanowires, leading towards reduced reverse leakage current and voltage enhancement

Mansoor Ahmad

Abstract

Here, we report the adsorption effect of NO2 on ZnO (100 nm) nanowires. We have studied the effect of adsorbed NO2 molecules on ZnO nanowire-based energy harvester for an exposure time of 1, 2, 3, 4, 5 and 6 h in a sealed chamber at 50 ppm which yielded piezoelectric voltage of 543.6 mV, 834.6 mV, 1.071 V, 1.78 V, 1.969 V and 2.835 V, respectively. We have thoroughly investigated the behaviour of ZnO nanowires in the presence of NO2 and observed a maximum output piezoelectric voltage of 2.835 V with a power density 158.2 mW cm-2. This is the first time that ZnObased piezoelectric energy harvester is being used for the voltage enhancement in the presence of NO2. We have used vertically integrated nanowire generator (VING) structure. X-ray diffraction pattern revealed the growth orientation of ZnO nanowires were along the c-axis from the substrate. ZnO nanowires were grown on indium tin oxide-coated polyethylene terephthalate substrates via a hydrothermal route. Surface morphology has be.....

Article Published 2020 921 hits Available

Adsorption effect of oxygen on ZnO Nanowires (100 nm) leading towards pronounced edge effects and voltage enhancement

Mansoor Ahmada

Abstract

Here, we report high output piezoelectric voltage generation from oxidized ZnO nanowires (100nm). Periodic high output voltage peaks were observed during series of oxygen exposure experiments. Gradual rise in piezoelectric potential from oxidized ZnO nanowires is being evidenced for the very first time. Sharp voltagepeaks 464mV, 803mV, 1.354 V, 1.795V and 2.44V are observed for an exposure of oxygen for 1h, 2h, 3h, 4h and 5h respectively in a sealed chamber at 50ppm. Ithas been observed maximum output value has been saturated after 5h of O exposure. Enhanced piezoelectric potential appearing at output stages is due to the adsorption of oxygen molecules on long ZnO nanowires, giving rise to “Edge Effects” and consequently reducing reverse leakage current through nanowires and enhancing output voltage. SEM images revealed the surface morphology ZnO nanowires, diameter range was found around 100nm. XRD pattern verified vertical growth orientation of ZnO nanowires on ITO (indium Tin o.....

Article Published 2020 951 hits Available

Chemisorbed CO2 molecules on ZnO nanowires (100 nm) surface leading towards enhanced piezoelectric voltage

Mansoor Ahmad

Abstract

Absract Here, we have studied the behavior of ZnO based piezoelectric mechanical transducer in the presence of CO2. We have analyzed reduction-oxidation mechanism of CO2 gas on ZnO nanowire surface and studied its behavior for the enhancement piezoelectric output voltage. Rise in piezoelectric potential for various CO2 exposures time intervals from 30min to 3 h has been observed. Chemiresistive behavior of CO2 modified ZnO nanowires, is being explained by the generation of high piezoelectric voltage. ZnO nanowires based nanogenerator has been exposed to 30 min, 60 min, 90 min, 120 min and 3 h in a sealed chamber at 20 ppm, corresponding output piezoelectric voltages of 503.9 mV, 1.15 mV, 1.559 V and 1.795 V have been recorded respectively by using Picoscope 5204. It has also been observed that output voltage value has been saturated after 2 h of CO2 exposure. ZnO nanowire based VING (vertically integrated nanowire generator) structure is being used for the study under minute external f.....

Article Published 2020 865 hits Available

Temperature dependant high output voltage generation via mechanical transducer by using surface modified (O2, CO2, NO2) ZnO nanowires

Mansoor Ahmad

Abstract

Here, we report high output piezoelectric voltage generation using ZnO nanowires oxidized at high temperature. The study has been carried out to observe behavior of ZnO nanowires in the presence of strong oxidizing gases (O, CO2, and NO2) at elevated temperature. The focus of the research was to generate high piezoelectric voltage by using surface modified ZnO nanowires. VING (vertically integrated nanowire generator) has been exposed to oxidizing gases. ZnO nanowires oxidized with O2 have shown maximum high output voltage of 3.36 V at 200o C, showing net rise of 0.762 V as compared to voltage generated at room temperature. Similarly, ZnO nanowires modified with CO2 molecules have generated piezoelectric voltage of 2.589 V at 200o C, exhibiting a rise of 0.778 V as compared to the values recorded at room temperature and ZnO nanowires modified with NO2 have generated maximum output voltage of 3.307 V at 150o C, indicating net rise of 0.59 V to the voltage values achieved at room tempera.....

Article Published 2021 799 hits Available

The Effectivenes of artfical intelligence in making smart decisions in the UAE public sektor

Al Nuaimi, Mansoor Abdulla

Abstract

This_ research_ aims_ to_ examine_ the_ impact_ of_ AI_ on_ organizational_ operations_ and_ efficiency, analyze its influence on expenditures, and scrutinize its effects on intelligent_ decision-making in UAE organizations. Supported by institutional theory, it employs a_ qualitative_ research_ design_ using_ a_ convenience_ sample_ of_ 38_ semi-structured_ interviews_ with_ high-ranking_ individuals_ in_ various_ public_ sector_ organizations_ conducted_ from_ April_ to_ October_ 2022._ The_ data_ were_ analyzed_ using NVIVO_ 12_ software_ through_ thematic_ analysis._ Results_ revealed_ that_ participants_ widely_ acknowledged AI's positive role in decision-making, highlighting its ability to automate_ tasks, save time, and allow human workers to focus on professional development and_ creativity._ Key_ themes_ identified_ include_ AI's_ transformative_ impact_ on_ customer_ services, reputation, and operational efficiency. Implementing AI reduced operational_ costs,_ improved_ maint.....

Thesis Published 2024 280 hits Available

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