Hydrogen

Over the past decade, hydrogen gas generation has been a critical component toward clean energy due to its high specific energy content. Generating hydrogen gas from water is crucial for future applications, including space transportation. Recent studies show promising results using silicon nanoparticles (SiNPs) for spontaneous hydrogen generation, but most methods require external energy like high temperature or pressure. In this work, we investigated hydrogen production from SiNPs without external energy by leveraging high pH water using sodium hydroxide and optimizing the process with a microfluidic approach. When comparing the physical dispersion methods using the 0.1 mg/mL case, ultrasonic bath produced more hydrogen than magnetic stirrer. In this thesis, 0.01% dextran with pure SiNPs at concentrations of 0.1 mg/mL, 0.2 mg/mL, and 0.3 mg/mL was analyzed. The highest concentration with dextran generated at least 40% less hydrogen than silicon alone, thus dextran did not increase hydrogen gas.

Time-resolved absolute intensity measurements have been made
on the Balmer series lines of a residual hydrogen impurity in a hollowcathode
helium afterglow plasma. From these measurements, the excited
state populations were calculated and revealed the existence of population
inversions in the excited states of hydrogen. In the hydrogen
afterglow the maximum average state population shifted upwards from
n = 3 at the beginning of the afterglow to progressively higher states
until in the late afterglow the maximum population was at n = 6. The
effects of the helium metastables, both atomic and molecular, were
shown to offer no detectable contribution to the observed inversions.
Comparison with a theoretical model for a recombining pulsed hydrogen
plasma for which inversions had been predicted are favorable and
recomb ~nation processes are assumed responsible for the inversions in
the lower discrete levels in the hydrogen impurity.