A new way to produce clean hydrogen fuel from water using sunlight

A new way to produce clean hydrogen fuel from water using sunlight
Transmittance electron microscopic image of the composite photocatalyst with two components, black phosphorous (BP) and graphitic carbon nitride (g-C3N4). Credit: Osaka University

Osaka University-led researchers develop new metal-free photocatalyst and show visible and near infrared light-driven production of hydrogen from water.

Osaka – Hydrogen is the most abundant element in the universe, and is considered by many to be a potential clean fuel of the future. Water and fossil fuels contain large amounts of hydrogen, but unlocking molecular dihydrogen fuel from these sources takes a great deal of energy, casting doubt over any future hydrogen economy. Turning water into hydrogen using solar energy could lead the way to cheap and clean hydrogen fuel. However, this process currently relies on photocatalysts containing expensive precious metals, limiting its capacity.

Now, researchers centered at Osaka University have developed a new kind of photocatalyst for producing hydrogen from water, which is not only free of expensive metals but also absorbs a wider range of sunlight than ever before. The group recently reported their findings in the Journal of the American Chemical Society.

"We were pleased to find a good amount of hydrogen produced from water using our new composite photocatalyst with graphitic and black phosphorous," lead author Tetsuro Majima says. "But what we didn't expect to find was that even when using low-energy light, in the near infrared, the photocatalyst continued to produce hydrogen."

Like graphite, graphitic carbon nitride forms in large sheets, but carbon nitride sheets also have holes that can interact with . In the past, photocatalysts based on carbon nitride have needed help from precious metals to produce hydrogen from water. The researchers found the metal could be replaced by a kind of phosphorus, which is a widely abundant and inexpensive element.

They showed that their photocatalyst was effective for producing hydrogen from water using energy from different kinds of light. Most unusually, even near infrared light with low energy could drive the .

Studies of the working photocatalyst in the picosecond time scale revealed that strong interactions between the nitride and black phosphorous in the composite promoted hydrogen production. When the two materials were tested separately, energy from the sunlight was rapidly dissipated and little or no hydrogen was produced.

Lead author Tetsuro Majima says, "The hydrogen economy faces a great many challenges, but our work demonstrates the potential for efficiently and cheaply producing hydrogen from with a based on widely abundant elements. This is an important step toward making other -based technologies economically and environmentally viable."


Explore further

Solar material for producing clean hydrogen fuel

More information: Mingshan Zhu et al. Metal-Free Photocatalyst for H2 Evolution in Visible to Near-Infrared Region: Black Phosphorus/Graphitic Carbon Nitride, Journal of the American Chemical Society (2017). DOI: 10.1021/jacs.7b08416
Provided by Osaka University
Citation: A new way to produce clean hydrogen fuel from water using sunlight (2017, October 4) retrieved 25 June 2019 from https://phys.org/news/2017-10-hydrogen-fuel-sunlight.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
43 shares

Feedback to editors

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more