Physics Commons^™

One-Step Laser-Induced Hydrogen Generation From Coal Powders In Water, Dovletgeldi Seyitliyev

Masters Theses & Specialist Projects

This study presents a simple way of obtaining hydrogen gas (H2) from various ranks of coal, coke, and graphite using nanosecond laser pulses. Powder samples of coal and graphite with and without water were irradiated with 1064 nm and 532 nm pulses from an Nd: YAG laser for 45 minutes under air and argon atmospheres. It was observed that 532 nm laser pulses were more effective than 1064 nm pulses in gas generation and both were nonlinearly correlated with respect to the laser energy density. Mainly hydrogen (H2) and carbon monoxide (CO) were observed. The H2 to CO ratio shows …

Graphene-Based ‘Hybrids’ As High-Performance Electrodes With Tailored Interfaces For Alternative Energy Applications: Synthesis, Structure And Electrochemical Properties, Mayme Marie Van Meveren

Masters Theses & Specialist Projects

Technological progress is determined to a great extent by developments of novel materials from new combinations of known substances with different dimensionality and functionality. We investigate the development of 3D ‘hybrid’ nanomaterials by utilizing graphene based systems coupled with transition metal oxides (e.g. manganese oxides MnO2 and Mn3O4). This lays the groundwork for high performance electrochemical electrodes for alternative energy owing to their higher specific capacitance, wide operational window and stability through charge-discharge cycling, environmental benignity, cost effective, easily processed, and reproducible in a larger scale.

Thus far, very few people have investigated the potential of combining carbon sheets that …

Synthesis, Characterization, And Properties Of Graphene-Based Hybrids With Cobalt Oxides For Electrochemical Energy Storage And Electrocatalytic Glucose Sensing, Sara C. Botero Carrizosa

Masters Theses & Specialist Projects

A library of graphene-based hybrid materials was synthesized as novel hybrid electrochemical electrodes for electrochemical energy conversion and storage devices and electrocatalytical sensing namely enzymeless glucose sensing. The materials used were supercapacitive graphene-family nanomaterials (multilayer graphene-MLG; graphene oxide-GO, chemically reduced GO-rGO and electrochemical reduced GOErGO) and pseudocapacitive nanostructured transition metal oxides including cobalt oxide polymorphs (CoO and Co3O4) and cobalt nanoparticles (CoNP). These were combined through physisorption, electrodeposition, and hydrothermal syntheses approaches. This project was carried out to enhance electrochemical performance and to develop electrocatalytic platforms by tailoring structural properties and desired interfaces. Particularly, electrodeposition and hydrothermal synthesis facilitate chemically-bridged …