Browsing by Author "Uhuo, Onyinyechi Vivian"

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    Kesterite-amplified aptameric nanobiosensors for interferon gamma Tuberculosis biomarker
    (University of the Western Cape, 2022) Uhuo, Onyinyechi Vivian; Iwuoha, Emmanuel I.
    Tuberculosis (TB) disease has continued to plague the world, infecting and killing thousands of men, women, and children yearly. Developing countries with limited access to power supply, standard laboratory facilities with special biosafety conditions, and trained medical personnel required for the current diagnostic techniques, experience high TB incidence and deaths yearly. The urgent need to eradicate TB globally can be met with improvement in TB diagnosis. Aptasensor approach to TB diagnosis offers a rapid, user-friendly, robust, highly sensitive, and selective means of detecting biomarkers of TB disease.
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    Novel heterojunction superstrate Cu2ZnInS4−x (CZIS) thin film kesterite solar cell with vertical arrays of hexagonal ZnO nanorods window layer
    (Elsevier, 2022-11-24) Yussuf, Sodiq Tolulope; Ramoroka, Morongwa Emmanuel; Mdluli, Siyabonga Beizel; Nwambaekwe, Kelechi Chiemezie; Ekwere, Precious Idinma; Uhuo, Onyinyechi Vivian; Ikpo, Chinwe Oluchi; Iwuoha, Emmanuel Iheanyichukwu
    Quaternary Cu2ZnInS4−x (CZIS) thin films have been prepared by a facile and cheap sol-gel spin coating technique. Low-temperature solution-based methods were used to fabricate a heterojunction solar cell in the superstrate architecture with CZIS thin film as the absorber, vertically aligned ZnO nanorod arrays, and CdS as the window and buffer layers respectively. ZnO nanorod arrays were prepared by hydrothermal technique and nanocrystal layer deposition technique were employed for the deposition of CdS-coated ZnO nanorod arrays. CZIS absorber layer was spin coated on the CdS-coated ZnO nanorod arrays and annealed at different temperatures. The vertically aligned ZnO nanorod arrays, and uniformly distributed CdS shell layer were confirmed from morphological studies. The device had a final configuration of Glass/ITO/ZnO NRs/CdS/ CZIS/Ag. HRSEM revealed a nanoflake-like morphology and a band gap between 1.5 and 1.77 eV for the CZIS thin films. CZIS superstrate solar cell had a power conversion efficiency of ∼ 0.61%, an open circuit voltage of ∼ 0.8 V, a short circuit current of ∼ 0.95 mA cm−2 and a fill factor of ∼ 61.35%. This method demonstrates a novel, facile and eco-friendly technique for synthesizing nanocrystalline CZIS thin films with promising photo response from the fabricated device indicating a proof of principle that this material can find application in solar cells.