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Fabrication and Electrocatalytic Properties of Metal Oxide – Metal Oxide Hybrids

Thesis Info

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Author

Mujtaba, Ayesha

Supervisor

Naveed Kausar Janjua

Program

PhD

Institute

Quaid-I-Azam University

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2016

Thesis Completion Status

Completed

Subject

Chemistry

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/2910/1/Ayesha%20Mujtaba%20Thesis.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726187210

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The primary objective of the present study was to exploit unusual and potentially unique properties of metal oxide coated metal oxide nanomaterials which were synthesized in two stages by adopting simple route. Five metal oxides: MgO, Al 2 O 3 , Fe 2 O 3 and CeO 2 were selected as substrate materials and prepared by simple precipitation method (except TiO 2 ). CuO was chosen as an active component and was loaded onto each substrate by impregnation technique. Five loads of CuO in 5, 10, 15, 20, 25 wt% compositions onto various substrates were prepared. The prepared nanomaterials were characterized by Fourier transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD), scanning electron microscopy (SEM) along with EDX analysis, transmission electron microscopy (TEM), particle size distribution (PSD) and BET-analysis. Glassy carbon electrode (A = 0.07 cm 2 ) was modified with each catalyst by drop-casting and used for investigating electrochemical behaviour in neutral (KCl), basic (KOH), acidic (H 2 SO 4 ) and PBS buffer solutions. Electrochemical studies on the prepared electrodes were done through electrochemical impedance spectroscopy (EIS) which revealed the conductive properties of synthesized hybrid nanomaterials and thus the electrocatalytically active ratio of CuO on respective substrates was assessed. 15CuO@MgO, 20CuO@Al 2 O 3 , 5CuO@TiO 2 , 10CuO@Fe 2 O 3 and 10CuO@CeO 2 presented better conductive properties in their respective series. Cyclic voltammetry (CV) was carried out to elucidate the redox behavior of these electroactive materials in H 2 SO 4 . Peak current-voltage (CV) responses of the modified electrodes in each hybrid catalyst series were in linearity with the CuO composition. Quantification of CuO in the respective catalysts was thus also made possible by using CV data in this technique. In order to explore the diverse role and investigate applications as potential electrocatalysts; electroxidation of two model analytes was carried out on all of the electrodes modified with the active hybrid materials. All the electrodes showed the potential to electrocatalyze glucose and methanol in alkaline media, however as predicted vis EIS studies; one optimal composition projected enhanced performance in each series; 20CuO@Al 2 O 3 , 5CuO@TiO 2 , ii10CuO@Fe 2 O 3 and 10CuO@CeO 2 . In CuO coated MgO series, 15CuO@MgO presented better electrocatalytic responses for ascorbic acid sensing in phosphate buffer solution at pH 7.4. This study scheme can be promoted for the electrochemical sensing of the biologically important analytes using the hybrid nanomaterials and also for the electrocatalysis applications. The synthesized nanomaterials possess potentiality for the future sensing and electrocatalysis smart technologies.
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ڈاکٹر سر راس مسعود

سرراس مسعود
افسوس ہے کہ ۳۰؍ جولائی ۱۹۳۷؁ء کی دوپہر کو ڈاکٹر سرراس مسعود کا بھوپال میں بعارضہ تپ میعادی انتقال ہوگیا، باہر والوں کو ان کی بیماری کی کوئی خبر نہ تھی، یکایک پہلی اگست کے اخباروں سے ان کی وفات کی اطلاع ملی، مسلمانوں کے لئے عموماً ور ان کے دوستوں کے لئے خصوصاً یہ سانحہ ہی المناک ہے، وہ ہماری قوم میں تعلیمی مسائل کے بڑے ماہر سمجھے جاتے تھے، سرسید کے پوتے اور جسٹس سید محمود کے بیٹے تھے، تعلیم سے فارغ ہوکر وہ پہلے پٹنہ میں ہیڈماسٹر ہوئے، وہاں سے کٹک پروفیسر ہوکر گئے، پھر حیدرآباد میں ناظم تعلیمات اور اس کے بعد مسلم یونیورسٹی کے وائس چانسلر اور آخر میں ریاست بھوپال میں وزیر تعلیم ہوئے، ۱۸۸۹؁ء میں پیدا ہوئے تھے، ۴۸ برس کی عمر پائی، جاپان کا تعلیمی نظم و نسق اور انتخاب زریں (اردو اشعار کا انتخاب) وغیرہ بعض رسالہ اور مضامین ان کی علمی اور ادبی یادگار ہیں، مرحوم نے دو جوان لڑکے پہلی بیوی سے چھوڑے ہیں، بڑا لڑکا تعلیم سے فارغ ہوکر اب یورپ سے واپس آگیا ہے۔
مرحوم بڑے وجیہہ، کشیدہ قامت، سرخ و سفید، ہنس مکھ اور ملنسار تھے، جس مجلس میں ہوتے سب پرچھا جاتے، باتوں کے دھنی اور زبان کے میٹھے تھے، ہر شخص سے جھک کر ملتے تھے، ایک ذاتی واقعہ ہے، مگر بیان کے قابل ہے، بارہ تیرہ برس ہوئے جب وہ حیدرآباد میں ناظم تعلیمات تھے، تو میرا حیدرآباد جانا اور ایک دوست کے ہاں ٹھہرنے کا اتفاق ہوا، جن سے پہلے گو ان سے بہت میل ملاپ تھا، مگر یکایک بیچ میں ایسی شکرنجی ہوگئی تھی کہ ملنا جلنا اور بات چیت تک بند ہوگئی تھی، میں جب ان سے جاکر ملا تو انہوں نے پوچھا کہاں ٹھہرے ہو، میں نے جگہ بتائی تو وہ چپ سے...

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