Generation of Hydrogen through the Reaction between Plasma‐Modified Aluminum and Water. Issue 12 (10th October 2017)

• Record Type: Journal Article
• Authors: Urbonavicius, Marius; Varnagiris, Sarunas; Milcius, Darius
• Is Part Of: Energy technology. Volume 5:Issue 12(2017:Dec.)
• Page Start: 2300
• Page End: 2308
• Publication Date: 2017-10-10
• Subjects: aluminum -- hydrogen -- plasma chemistry -- surface analysis -- water splitting; Energy development -- Periodicals; Power resources -- Periodicals; 333.79
• DOI: 10.1002/ente.201700344
• Languages: English
• ISSNs: 2194-4288

Abstract

Abstract: One of the main challenges related to hydrogen energy technologies is hydrogen storage in a safe and economically reasonable way. A promising solution could be related to the use of aluminum or its alloys to reduce water to form hydrogen when needed. The aluminum–water reaction is thermodynamically favorable, but does not proceed due to the passivation of the aluminum surface by the protective aluminum oxide layer, which prevents water molecules from coming into direct contact with metal particles. Herein, the surface of aluminum particles was modified by using a low‐temperature plasma‐activation approach. Such a modification induces a hydrophilicity effect and the modified aluminum powder sinks instantly in water, whereas unmodified powder floats on the top of the water. The plasma‐based activation technology is also discussed in detail. The structure and morphology of the samples were characterized by using SEM, energy‐dispersive X‐ray spectroscopy, and XRD. BET surface area analyses were also performed. The elemental composition on the nanoscale level and formation of polar groups were experimentally investigated by using X‐ray photoelectron spectroscopy. Amounts of oxygen/hydrogen were measured by using the inert‐gas fusion method. Tests show that hydrogen production starts after 1 min of aluminum powder immersion into slightly alkaline water and continues for up to 20 min. The reaction by‐product is environmentally friendly and could be used for the production of aluminum oxide. Abstract : Plasma‐induced polar groups : Aluminum powder is activated by treatment with a low‐temperature glow discharge plasma. Plasma induces a decrease in aluminum hydroxyl groups and the formation of polar groups at the uppermost surface of the activated aluminum powder. This leads to transformation into a hydrophilic surface and efficient reaction with water.