Safe and inexpensive hydrogen production as a future energy source

December 20, 2016

Osaka, Japan - Hydrogen gas is a promising alternative energy source to overcome our reliance on carbon-based fuels, and has the benefit of producing only water when it is reacted with oxygen. However, hydrogen is highly reactive and flammable, so it requires careful handling and storage. Typical hydrogen storage materials are limited by factors like water sensitivity, risk of explosion, difficulty of control of hydrogen-generation. Hydrogen gas can be produced efficiently from organosilanes, some of which are suitably air-stable, non-toxic, and cheap. Catalysts that can efficiently produce hydrogen from organosilanes are therefore desired with the ultimate goal of realizing safe, inexpensive hydrogen production in high yield. Ideally, the catalyst should also operate at room temperature under aerobic conditions without the need for additional energy input.

A research team led by Kiyotomi Kaneda and Takato Mitsudome at Osaka University have now developed a catalyst that realizes efficient environmentally friendly hydrogen production from organosilanes. The catalyst is composed of gold nanoparticles with a diameter of around 2 nm supported on hydroxyapatite. The catalyst was synthesized from chloroauric acid using glutathione as a capping agent to prevent nanoparticle aggregation, resulting the formation of small size of gold nanoparticles. Glutathione-capped gold nanoparticles were then adsorbed on hydroxyapatite and glutathione was removed by subsequent calcination.

The team then added the nanoparticle catalyst to solutions of different organosilanes to measure its ability to induce hydrogen production. The nanoparticle catalyst displayed the highest turnover frequency and number attained to date for hydrogen production catalysts from organosilanes. For example, the nanoparticle catalyst converted 99% of dimethylphenylsilane to the corresponding silanol in just 9 min at room temperature, releasing an equimolar amount of hydrogen gas at the same time. Importantly, the catalyst was recyclable without loss of activity. On/off switching of hydrogen production was achieved using the nanoparticle catalyst because it could be easily separated from its organosilane substrate by filtration. The activity of the catalyst increased as the nanoparticle size decreased.

A prototype portable hydrogen fuel cell containing the nanoparticle catalyst and an organosilane substrate was fabricated. The fuel cell generated power in air at room temperature and could be switched on and off as desired. Images of the catalyst after use in the fuel cell resembled those of the unused catalyst, indicating that the hydroxyapatite-supported nanoparticle catalyst readily resisted aggregation.

Generation of hydrogen from inexpensive organosilane substrates under ambient conditions without additional energy input represents an exciting advance towards the goal of using hydrogen as a green energy source.
The article "On-demand Hydrogen Production from Organosilanes at Ambient Temperature Using Heterogeneous Gold Catalysts" was published in Scientific Reports (DOI: 10.1038/srep37682).

Osaka University

Related Hydrogen Articles from Brightsurf:

Solar hydrogen: let's consider the stability of photoelectrodes
As part of an international collaboration, a team at the HZB has examined the corrosion processes of high-quality BiVO4 photoelectrodes using different state-of-the-art characterisation methods.

Hydrogen vehicles might soon become the global norm
Roughly one billion cars and trucks zoom about the world's roadways.

Hydrogen economy with mass production of high-purity hydrogen from ammonia
The Korea Institute of Science and Technology (KIST) has made an announcement about the technology to extract high-purity hydrogen from ammonia and generate electric power in conjunction with a fuel cell developed by a team led by Young Suk Jo and Chang Won Yoon from the Center for Hydrogen and Fuel Cell Research.

Superconductivity: It's hydrogen's fault
Last summer, it was discovered that there are promising superconductors in a special class of materials, the so-called nickelates.

Hydrogen energy at the root of life
A team of international researchers in Germany, France and Japan is making progress on answering the question of the origin of life.

Hydrogen alarm for remote hydrogen leak detection
Tomsk Polytechnic University jointly with the University of Chemistry and Technology of Prague proposed new sensors based on widely available optical fiber to ensure accurate detection of hydrogen molecules in the air.

Preparing for the hydrogen economy
In a world first, University of Sydney researchers have found evidence of how hydrogen causes embrittlement of steels.

Hydrogen boride nanosheets: A promising material for hydrogen carrier
Researchers at Tokyo Institute of Technology, University of Tsukuba, and colleagues in Japan report a promising hydrogen carrier in the form of hydrogen boride nanosheets.

World's fastest hydrogen sensor could pave the way for clean hydrogen energy
Hydrogen is a clean and renewable energy carrier that can power vehicles, with water as the only emission.

Chemical hydrogen storage system
Hydrogen is a highly attractive, but also highly explosive energy carrier, which requires safe, lightweight and cheap storage as well as transportation systems.

Read More: Hydrogen News and Hydrogen Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to