Materials Chemistry Commons^™

Effect Of The Electrodeposition Potential Of Platinum On The Catalytic Activity Of A Pt/Gc Catalyst Toward Formic Acid Electro−Oxidation, Islam M. Al-Akraa, Bilquis A. Al-Qodami Ms., Ahmad M. Mohammad Prof

Chemical Engineering

The electrocatalytic activity of platinum (Pt)–modified glassy carbon (GC) (referred as Pt/GC) electrodes toward the formic acid electro−oxidation (FAO) was investigated. The Pt deposition on the GC substrate was carried out by a potentiostatic technique at different potentials (from 0.2 V to −0.2 V vs. Hg/Hg2Cl2/KCl (sat.) reference electrode) and the corresponding influence on the catalytic activity toward FAO was monitored. The electrocatalytic inspection revealed a potential role for the Pt deposition potential in boosting the catalytic efficiency of the catalyst toward FAO and further in mitigating the CO poisoning that eventually deactivate the catalyst. Interestingly, the highest activity toward …

Ni-Au Anodic Nano-Electrocatalyst For Direct Glucose Fuel Cells, Islam M. Al-Akraa, Aya S. Abdulhalim Eng, Yassr M. Asal Mr, Ahmad M. Mohammad Prof

Chemical Engineering

This study aims at the sequential assembling of a nickel oxide (NiOx: cauliflower-like nanostructure, 90 nm) and gold (Au; spherical, 95 nm in an average particle size) onto the GC surface nanocatalyst on a glassy carbon (GC) electrode (will be abbreviated as Ni-Au/GC) for the glucose electro−oxidation (GO); the principal anodic reaction in the direct glucose fuel cells (DGFCs). The charge of the Ni deposition on the GC surface (will be abbreviated as Ni/GC electrode) was initially optimized to obtain the highest catalytic activity toward GO which attained at (339.8 Ag−1) by applying 15 mC in the Ni deposition. Yet, …

Enhanced Glucose Electrooxidation At Ni-Cu Binary Oxide Nanocatalyst, Islam M. Al-Akraa, Mahmoud M. Abouzaid Eng, Yaser M. Asal Mr, Ahmad M. Mohammad Prof

Chemical Engineering

The aim of this study is to fabricate a nickel (NiOx) and copper (CuOx) oxide nanocatalyst on a glassy carbon (GC) electrode (will be abbreviated as Ni-Cu/GC) for glucose oxidation (GO). A sequential electrodepositon mode was applied to assemble NiOx and CuOx in the fabrication scheme. The optimization of Ni loading on the GC surface (will be abbreviated as Ni/GC electrode) was achieved first to attain the maximum catalytic efficiency in terms of the specific current toward GO. This (409 Ag1)was obtained by applying 15 mC/cm2 in the deposition of Ni. However, unfortunately the NiOx/GC could not support a long-term …

A Spin-Coated Tiox/Pt Nanolayered Anodic Catalyst For The Direct Formic Acid Fuel Cells, Islam M. Al-Akraa, Ahmad M. Mohammad Prof

Chemical Engineering

The CO poisoning of the platinum anodic catalyst which typically functions the catalytic deterioration of the direct formic acid fuel cells could be minimized with a simple modification for Pt with titanium oxide. The fabrication scheme involved the spin-coating of a Ti precursor onto a Pt thin layer that was physically sputtered onto a Si substrate. The whole assembly was subjected to a post-annealing processing to produce the TiOx layer (60 nm) in a porous structure (mostly Anatase) atop of the Pt surface. The porous nature of the TiOx layer permitted the participation of Pt in the electrocatalysis of the …

Tuning The Activity And Stability Of Platinum Nanoparticles Toward The Catalysis Of The Formic Acid Electrooxidation, Islam M. Al-Akraa, Bilquis A. Al-Qodami, Santosh Sridhar Mysore Dr, R. Viswanatha Dr, Abdul Kareem Thottoli, Ahmad M. Mohammad

Chemical Engineering

No abstract provided.

Singlet Fission In A Hexacene Dimer: Energetics Dictate Dynamics, Samuel N. Sanders, Elango Kumarasamy, Kealan J. Fallon, Matthew Y. Sfeir, Luis M. Campos

Publications and Research

Singlet fission (SF) is an exciton multiplication process with the potential to raise the efficiency limit of single junction solar cells from 33% to up to 45%. Most chromophores generally undergo SF as solid-state crystals. However, when such molecules are covalently coupled, the dimers can be used as model systems to study fundamental photophysical dynamics where a singlet exciton splits into two triplet excitons within individual molecules. Here we report the synthesis and photophysical characterization of singlet fission of a hexacene dimer. Comparing the hexacene dimer to analogous tetracene and pentacene dimers reveals that excess exoergicity slows down singlet fission, …

Synthesis Of Graphene Using Plasma Etching And Atmospheric Pressure Annealing: Process And Sensor Development, Andrew Robert Graves

Graduate Theses, Dissertations, and Problem Reports (ETD)

Having been theorized in 1947, it was not until 2004 that graphene was first isolated. In the years since its isolation, graphene has been the subject of intense, world-wide study due to its incredibly diverse array of useful properties. Even though many billions of dollars have been spent on its development, graphene has yet to break out of the laboratory and penetrate mainstream industrial applications markets. This is because graphene faces a ‘grand challenge.’ Simply put, there is currently no method of manufacturing high-quality graphene on the industrial scale. This grand challenge looms particularly large for electronic applications where the …

Redox-Active Porous Organic Materials For Electrochemical Energy Storage Applications, K. Shamara Weeraratne

Theses and Dissertations

As the demand for renewable energy technologies grows, so does the need for cheaper, more efficient rechargeable batteries to store the energy. While lithium-ion battery (LIBs) technology is well established, it suffers from limited lithium supplies. Furthermore, the highly toxic transition metals used in the electrodes places a huge burden on the environment. Therefore, replacing lithium with more economical sodium metal in rechargeable batteries (i.e. sodium-ion batteries, SIBs) has garnered considerable attention. Despite the fact that sodium and lithium share similar electrochemical properties, which may cause the transition from lithium to sodium easier, the larger ionic radius of Na^{+ …}

Metal-Oxide Nanostructures Fabricated From Reactive Laser Ablation In Liquid, Mallory G. John

Theses and Dissertations

The development of metal-oxide nanostructures is a growing area due to their applications in diverse fields spanning energy conversion and storage, chemical manufacturing, and en- vironmental technology. This interest in catalytically active nanomaterials has prompted the synthesis and investigation of highly functionalized nanoparticles (NPs), including core- shell, silicate-stabilized, and bi- and multi-metallic nanocomposites. While wet-chemical synthesis methods of metal-oxide nanostructures have led to several morphologies, compositions, and shapes, these syntheses often require high temperatures, toxic solvents or reducing agents, and long reaction times.

Laser synthesis and processing of colloids (LSPC) encompasses both ‘top down’ and ‘bottom up’ approaches to synthesize …