Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


From Stench to Resource


Production of sulfur and hydrogen: splitting hydrogen sulfide with solar energy

No one who has cracked open a rotten egg will forget its infernal stench. Biofuel plants, sewage treatment plants, and petroleum refineries can generate substantial amounts of foul-smelling hydrogen sulfide gas, which is highly toxic at higher concentrations.

In the journal Angewandte Chemie, a team of Australian and Chinese researchers has now introduced an innovative photoelectrochemical process in which solar energy is used to split this undesirable by-product into sulfur and hydrogen, converting it to a source of raw materials.

A variety of techniques have been used to remove hydrogen sulfide (H2S) from polluted exhaust gases and occasionally put it to further use. While sulfur can be extracted in some processes, the hydrogen cannot. This is unfortunate because hydrogen is actually an important energy source for future fuel-cell technology.

... more about:
»Hydrogen »electrons »protons »redox »sulfide »sulfur »sunlight

Unfortunately, it isn’t possible to split H2S to gain hydrogen and sulfur simultaneously. Approaches using photochemical splitting seem particularly attractive because solar energy could be used to meet the high energy demand of this reaction.

However, no ecologically and economically feasible process has been found to date. This could now change thanks to a new approach developed by a team headed by Lianzhou Wang (University of Queensland, Australia) and Can Li (Chinese Academy of Sciences and Dalian Laboratory for Clean Energy, China).

Their success lies in a photochemical–chemical loop whose reactions are coupled through a redox pair. A redox pair is a combination of the reduced and oxidized form of the same element that can easily be interconverted. For their process, the researchers used either divalent and trivalent iron ions (Fe2+/Fe3+) or the iodide/triiodide (I/I3) system.

The hydrogen sulfide gas is introduced into the electrolyte of the anodic compartment of an electrochemical cell. Here, a chemical reaction causes it to be bound to the oxidized form of the redox pair (which is thus reduced) and converted to sulfur, which precipitates out as a yellow solid, and hydrogen cations (protons).

The protons can pass through the semipermeable membrane that separates the anodic and cathodic compartments. The second reaction is photoelectrochemical: as protons are reduced at the cathode by taking up electrons, the reduced form of the redox pair is returned to its oxidized state by giving up electrons at the anode. The driving force for this is sunlight, which generates “electron–hole pairs” at the photoanode. These holes can then be filled by the absorbed electrons.

The redox pairs continuously cycle between the oxidized and reduced forms so that the overall reaction is the splitting of hydrogen sulfide into sulfur and hydrogen by sunlight.

About the Author

Dr. Lianzhou Wang is a Professor at the School of Chemical Engineering and Research Director of Nanomaterials Centre, the University of Queensland (UQ), Australia. His main research interests include the design and development of semiconducting nanomaterials for applications in renewable energy conversion/storage systems, including photocatalysis, new-generation solar cells, and rechargeable batteries.

Author: Lianzhou Wang, University of Queensland (Australia),

Title: An Integrated Photoelectrochemical–Chemical Loop for Solar-Driven Overall Splitting of Hydrogen Sulfide

Angewandte Chemie International Edition, Permalink to the article:

Lianzhou Wang | Angewandte Chemie International Edition

Further reports about: Hydrogen electrons protons redox sulfide sulfur sunlight

More articles from Life Sciences:

nachricht ‘Farming’ bacteria to boost growth in the oceans
24.10.2016 | Max-Planck-Institut für marine Mikrobiologie

nachricht Calcium Induces Chronic Lung Infections
24.10.2016 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Oasis of life in the ice-covered central Arctic

24.10.2016 | Earth Sciences

‘Farming’ bacteria to boost growth in the oceans

24.10.2016 | Life Sciences

Light-driven atomic rotations excite magnetic waves

24.10.2016 | Physics and Astronomy

More VideoLinks >>>