Graphene could soon be facing some competition for the unofficial title of “World’s Most Useful New Substance.” Led by Associate Professor Darren Sun, a team of scientists at Singapore’s Nanyang Technological University have spent the past five years developing a material known as Multi-use Titanium Dioxide. Their research indicates that it can be used to produce hydrogen and clean water from wastewater, double the lifespan of batteries, create antibacterial wound dressings ... and more.
Sun first got the idea for Multi-use Titanium Dioxide when he was trying to develop antibacterial water filters that resisted biofouling. The material is made by converting inexpensive titanium dioxide crystals into nanofibers, which are then incorporated into flexible filter membranes. Depending on the intended use of the material, those membranes can also include a mixture of carbon, copper, zinc and/or tin.
When used to treat wastewater, the substance does two main things. First, it serves as an efficient, anti-fouling, low-cost filtration membrane, allowing water molecules to flow through easily while blocking the passage of contaminants – when used as a forward osmosis filter, it also keeps salt from passing through, allowing it to be used in desalination plants.
Secondly, when exposed to sunlight, it separates hydrogen from the wastewater for subsequent use in fuel cells or power plants. It’s able to generate 1.53 milliliters of hydrogen from one liter of wastewater per hour, which is reportedly three times better than what’s currently possible using the traditional costly catalyst, platinum.
The scientists have also created a black version of the material in which the titanium dioxide is in crystalline form. This was used in a functioning flexible solar cell, and may find use in next-generation lithium-ion batteries. In a previous study, it was found that li-ion batteries with anodes made from carbon-modified titanium dioxide nanoparticles had twice the capacity of their conventional counterparts.
Additionally, Multi-use Titanium Dioxide’s anti-microbial qualities could allow the membranes to be used in breathable, bacteria-killing wound dressings.
Sun and his team are now in the process of forming a spinoff company to develop the technology further, and are seeking partners to help commercialize the material.
Source: Nanyang Technological University
You apply forward osmosis, so that your feed (seawater) flows into a reusable brine solution (salt) that is concentrated by osmostic pressure. In a second step, you apply reverse osmosis which requires energy and you get purified water. The advantage of doing this is that forward osmosis filters are more resistance to fouling than reverse osmosis filters are.
If it separates hydrogen from waste water what would be left behind? Hydrogen peroxide ? If I remember my chemistry correctly platinum catalyst based hydrogen generators give you both, hydrogen and oxygen at the 2 electrodes.