The performance of multi-bed pressure swing adsorption (PSA) process for producing high purity hydrogen from synthesis gas was studied experimentally and theoretically using layered beds of activated carbon and zeolite 5A. Nonisothermal and nonadiabatic models, considering linear driving force model and Dual-site Langmuir adsorption isotherm model, were used. The effects of the following PSA variables on separation process were investigated: linear velocity of feed, adsorption time and purge gas quantity. As a result, we recovered a high purity H 2 product (99.999%) with a recovery of 66% from synthesis gas when the pressure was cycled between 1 and 8 atm at ambient temperature.

Hydrogen storage in the form of a liquid chemical is an important issue that can bridge the gap between sustainable hydrogen production and utilization with a fuel cell, which is one of the essential sectors in the hydrogen economy. Herein, the application of a potential liquid organic hydrogen carrier, consisting of biphenyl and diphenylmethane, is demonstrated as a safe and economical hydrogen storage material. The presented material is capable of a reversible storage and release of molecular hydrogen with 6.9 wt % and 60 g-H2 L–1 of gravimetric and volumetric hydrogen storage capacities, respectively, presenting superior properties as a hydrogen carrier. Equilibrium conversion and the required enthalpies of dehydrogenation are calculated using a density functional theory. Experimentally, dehydrogenation conversion of greater than 99% is achieved, producing molecular hydrogen with greater than 99.9% purity, with negligible side reactions; this is further confirmed by nuclear magnetic resonance spectroscopy. Less than 1% of the material is lost after cyclic tests of hydrogenation and dehydrogenation were conducted consecutively nine times. Finally, a dehydrogenation system is designed and operated in conjunction with a polymer electrolyte membrane fuel cell that can generate greater than 0.5 kW of electrical power in a continuous manner, proving its capability as a promising liquid organic hydrogen carrier.

In-Ga-Zn-O (IGZO) films deposited by sputtering process generally require thermal annealing above 300°C to achieve satisfactory semiconductor properties. In this work, microwave and e-beam radiation are adopted at room temperature as alternative activation methods. Thin film transistors (TFTs) based on IGZO semiconductors that have been subjected to microwave and e-beam processes exhibit electrical properties similar to those of thermally annealed devices. However spectroscopic ellipsometry analyses indicate that e-beam radiation may have caused structural damage in IGZO, thus compromising the device stability under bias stress.

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Zinc oxynitride (ZnON) has the potential to overcome the performance and stability limitations of current amorphous oxide semiconductors because ZnON-based thin-film transistors (TFTs) have a high field-effect mobility of 50 cm2/Vs and exceptional stability under bias and light illumination. However, due to the weak zinc–nitrogen interaction, ZnON is chemically unstableN is rapidly volatilized in air. As a result, recent research on ZnON TFTs has focused on improving air stability. We demonstrate through experimental and first-principles studies that the ZnF2/ZnON bilayer structure provides a facile way to achieve air stability with carrier controllability. This increase in air stability (e.g., nitrogen non-volatilization) occurs because the ZnF2 layer effectively protects the atomic mixing between ZnON and air, and the decrease in the ZnON carrier concentration is caused by a shallow-to-deep electronic transition of nitrogen deficiency diffused from ZnON into the interface. Further, the TFT based on the ZnF2/ZnON bilayer structure enables long-term air stability while retaining an optimal switching property of high field-effect mobility (∼100 cm2/Vs) even at a relatively low post-annealing temperature. The ZnF2/ZnON-bilayer TFT device exhibits fast switching behavior between 1 kHz and 0.1 MHz while maintaining a stable and clear switching response, paving the way for next-generation high-speed electronic applications.