Paint these days is becoming much more than it used to be. Already researchers have developed photovoltaic paint, which can be used to make “paint-on solar cells” that capture the sun’s energy and turn it into electricity. Now in a new study, researchers have created thermoelectric paint, which captures the waste heat from hot painted surfaces and converts it into electrical energy.
Plant life also helps to reduce humanity’s carbon footprint, sucking up about 25 percent of our carbon emissions to produce fuel for itself during photosynthesis. The only problem is, nature’s system for doing this is pretty slow and inefficient, but what if it could be boosted?
That’s the thinking behind a new study from German researchers, who have developed a synthetic system to incorporate CO2 into organic compounds – called carbon fixation – which is both dramatically faster than nature’s method and more energy efficient.
When plants absorb carbon during what’s known as the Calvin cycle – the second stage of photosynthesis – an enzyme called RuBisCO helps catalyse the reaction that turns CO2 into glucose, which plants use as an energy source.
The drawback with this system, according to lead researcher Tobias Erb from the Max Planck Institute for Terrestrial Microbiology, is that RuBisCO itself isn’t exactly quick, which holds the whole process up.
“RuBisCO is slow,” he told William Herkewitz at Popular Mechanics, adding that it’s also error-prone.
“[I]t backfires often, meaning about every fifth attempt RuBisCO will mix up CO2 with oxygen gas,” he explains, which further slows carbon absorption.
To see if they could engineer a better artificial system, Erb’s team sifted through a library of some 40,000 known enzymes from all walks of life.
“Some enzymes are found in the human body, and gut bacteria,” he says, while others were sourced “from plants, and microbes that live in the oceans and on the surface of plants”.
From this massive catalogue, the researchers ended up identifying 17 different enzymes from 9 different organisms, and engineered them into a new 11-step system that effectively recreates the Calvin cycle – but with superior results.
These enzymes, which belong to a group called ECRs, could pave the way for a new kind of organic carbon capture system that’s potentially way more effective than the shrub on your window sill.
“ECRs are supercharged enzymes that are capable of fixing CO2 at the rate of nearly 20 times faster than the most widely prevalent CO2-fixing enzyme in nature, RuBisCo, which carries out the heavy lifting involved in photosynthesis,” Erb said in a press release.
Given that the process has only been trialled in a test tube so far, it’s too early to say how much faster the system could be at capturing atmospheric carbon in the real world.
Superconductors are materials that conduct electricity with no resistance. The phenomenon was first discovered by Dutch physicist Heike Kamerlingh Onnes, who in 1911 saw mercury’s resistance drop to zero at 4.2 degrees above absolute zero. Other materials were found to be superconducting at slightly higher temperatures, but the need for extreme refrigeration limited the usefulness of the phenomenon.
Until 1986, that is. That was when we discovered the high temperature superconductors, which abruptly stop resisting below roughly 100 kelvin (which is -170 °C: the term “high temperature” is a relative one). Suddenly, creating room temperature superconductors didn’t seem so far-fetched.
That second great leap forward hasn’t happened – yet. So far we have not bettered what we found 30 years ago, says Paul Attfield of the University of Edinburgh, UK. Materials have been discovered that superconduct at somewhat higher temperatures, but only when under extremely high pressures.
For now, superconductors remain entirely impractical for the killer applications that would allow them to change the world: transport and electrical power transmission.