Tiny 'skyscrapers' help bacteria convert sunlight into electricity


Date:
March 7, 2022
Source:
University of Cambridge
Summary:
Researchers have made tiny 'skyscrapers' for communities of
bacteria, helping them to generate electricity from just sunlight
and water.



FULL STORY ========================================================================== Researchers have made tiny 'skyscrapers' for communities of bacteria,
helping them to generate electricity from just sunlight and water.


==========================================================================
The researchers, from the University of Cambridge, used 3D printing to
create grids of high-rise 'nano-housing' where sun-loving bacteria can
grow quickly.

The researchers were then able to extract the bacteria's waste electrons,
left over from photosynthesis, which could be used to power small
electronics.

Other research teams have extracted energy from photosynthetic bacteria,
but the Cambridge researchers have found that providing them with the
right kind of home increases the amount of energy they can extract
by over an order of magnitude. The approach is competitive against
traditional methods of renewable bioenergy generation and has already
reached solar conversion efficiencies that can outcompete many current
methods of biofuel generation.

Their results, reported in the journal Nature Materials, open new avenues
in bioenergy generation and suggest that 'biohybrid' sources of solar
energy could be an important component in the zero-carbon energy mix.

Current renewable technologies, such as silicon-based solar cells and
biofuels, are far superior to fossil fuels in terms of carbon emissions,
but they also have limitations, such as a reliance on mining, challenges
in recycling, and a reliance on farming and land use, which results in biodiversity loss.

"Our approach is a step towards making even more sustainable renewable
energy devices for the future," said Dr Jenny Zhang from the Yusuf Hamied Department of Chemistry, who led the research.



========================================================================== Zhang and her colleagues from the Department of Biochemistry and the
Department of Materials Science and Metallurgy are working to rethink
bioenergy into something that is sustainable and scalable.

Photosynthetic bacteria, or cyanobacteria, are the most abundant life
from on Earth. For several years, researchers have been attempting to
're-wire' the photosynthesis mechanisms of cyanobacteria in order to
extract energy from them.

"There's been a bottleneck in terms of how much energy you can actually
extract from photosynthetic systems, but no one understood where the
bottleneck was," said Zhang. "Most scientists assumed that the bottleneck
was on the biological side, in the bacteria, but we've found that a
substantial bottleneck is actually on the material side." In order to
grow, cyanobacteria need lots of sunlight -- like the surface of a lake
in summertime. And in order to extract the energy they produce through photosynthesis, the bacteria need to be attached to electrodes.

The Cambridge team 3D-printed custom electrodes out of metal oxide nanoparticles that are tailored to work with the cyanobacteria as they
perform photosynthesis. The electrodes were printed as highly branched,
densely packed pillar structures, like a tiny city.



========================================================================== Zhang's team developed a printing technique that allows control over
multiple length scales, making the structures highly customisable,
which could benefit a wide range of fields.

"The electrodes have excellent light-handling properties, like a high-rise apartment with lots of windows," said Zhang. "Cyanobacteria need something
they can attach to and form a community with their neighbours. Our
electrodes allow for a balance between lots of surface area and lots of
light -- like a glass skyscraper." Once the self-assembling cyanobacteria
were in their new 'wired' home, the researchers found that they were more efficient than other current bioenergy technologies, such as biofuels. The technique increased the amount of energy extracted by over an order of magnitude over other methods for producing bioenergy from photosynthesis.

"I was surprised we were able to achieve the numbers we did --
similar numbers have been predicted for many years, but this is the
first time that these numbers have been shown experimentally," said
Zhang. "Cyanobacteria are versatile chemical factories. Our approach
allows us to tap into their energy conversion pathway at an early point,
which helps us understand how they carry out energy conversion so we can
use their natural pathways for renewable fuel or chemical generation."
The research was supported in part by the Biotechnology and Biological
Sciences Research Council, the Cambridge Trust, the Isaac Newton Trust
and the European Research Council. Jenny Zhang is BBSRC David Phillips
Fellow in the Department of Chemistry, and a Fellow of Corpus Christi
College, Cambridge.

========================================================================== Story Source: Materials provided by University_of_Cambridge. The original
text of this story is licensed under a Creative_Commons_License. Note:
Content may be edited for style and length.


========================================================================== Related Multimedia:
* 3D-printed_custom_electrodes ========================================================================== Journal Reference:
1. Xiaolong Chen, Joshua M. Lawrence, Laura T. Wey, Lukas Schertel,
Qingshen
Jing, Silvia Vignolini, Christopher J. Howe, Sohini Kar-Narayan,
Jenny Z.

Zhang. 3D-printed hierarchical pillar array electrodes for high-
performance semi-artificial photosynthesis. Nature Materials,
2022; DOI: 10.1038/s41563-022-01205-5 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2022/03/220307113020.htm

--- up 1 week, 10 hours, 51 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)