Sunlight to fuel: Cambridge’s new breakthrough in clean energy

https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

The Natural Philosopher

2025-02-27 11:24:22 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

--
In theory, there is no difference between theory and practice.
In practice, there is.
-- Yogi Berra

Theo

2025-02-27 12:36:39 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.

Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.

The paper is here:
https://www.nature.com/articles/s41560-025-01714-y

Tim Streater

2025-02-27 12:43:18 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

Yeah, that's what I looked at. It's too turgid for me to read in detail,
however, and just now I'm busy doing nothing so I'll have to put off reading
it carefully for a century or so.

--
"A committee is a cul-de-sac down which ideas are lured and then quietly strangled." - Sir Barnett Cocks (1907-1989)

Jeff Layman

2025-02-27 13:59:46 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).

Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.

Fig.1d has a reaction at the top:
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

Any clarification gratefully received.

--
Jeff

Tim Streater

2025-02-27 16:32:37 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

Well I dunno for sure. But the reaction seems to be taking place over a
substrate of glycolaldehyde (HOCH2−CHO) and other substances. Perhaps with an
input on sunlght (UV?) it catalyses the breakdown of the glycolaldehyde:

HOCH2−CHO -> 2CO + 2H2

but I'm just guessing. Do we have a real chemical engineer on the strength?

--
Tim

Tim Streater

2025-02-27 16:54:52 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

Well I dunno for sure. But the reaction seems to be taking place over a
substrate of glycolaldehyde (HOCH2−CHO) and other substances. Perhaps with an
HOCH2−CHO -> 2CO + 2H2
but I'm just guessing. Do we have a real chemical engineer on the strength?

OK - belay that. The actual substrate seems to be mineral only, no organics.
The glycolaldehyde and the formate appear to be outputs, not inputs.

--
Tim

Jeff Layman

2025-02-27 18:30:50 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

OK - belay that. The actual substrate seems to be mineral only, no organics.
The glycolaldehyde and the formate appear to be outputs, not inputs.

Indeed. Even if the glycolaldehyde was an input, where does it come
from? Its synthesis, according to the wiki, is from glycol and H2O2. And
that just pushes the "hydrogen" question further down the line! There is
the possibility of biosynthesis, and that's mentioned in the wiki.

Paul's reply downthread has an interesting ref at
<https://www.cam.ac.uk/research/news/artificial-leaf-successfully-produces-clean-gas>.
That 2019 report mentions the use of sunlight, carbon dioxide and
*water* (hooray - a source of hydrogen!) to make syngas. The original
paper (in Nature Materials) which is referenced in that report isn't
mentioned in the Nature Energy paper we've been discussing. Shrug...

--
Jeff

Paul

2025-02-28 06:50:55 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

OK - belay that. The actual substrate seems to be mineral only, no organics.
The glycolaldehyde and the formate appear to be outputs, not inputs.

Indeed. Even if the glycolaldehyde was an input, where does it come from? Its synthesis, according to the wiki, is from glycol and H2O2. And that just pushes the "hydrogen" question further down the line! There is the possibility of biosynthesis, and that's mentioned in the wiki.
Paul's reply downthread has an interesting ref at <https://www.cam.ac.uk/research/news/artificial-leaf-successfully-produces-clean-gas>. That 2019 report mentions the use of sunlight, carbon dioxide and *water* (hooray - a source of hydrogen!) to make syngas. The original paper (in Nature Materials) which is referenced in that report isn't mentioned in the Nature Energy paper we've been discussing. Shrug...

I can see the "green-ness" of their electron donor half reaction source
material (basically it is the recycling of PET plastic). They apparently
used other electron donors of lower complexity as well. Having decided to
make a virtue of that feature of their scheme, they should have written
up the two half reactions in standard form, for the layman to enjoy.

If the H is coming from water, show it.

If the H is coming from the PET, show it.

The important part of this paper, is the cat. Not
the part about grinding up used cola bottles to make
PET for recycling.

The PET + ethylene glycol they use as inputs, these
are also materials found in the reaction vessel of
the plant that made the PET in the first place. These
are materials included as part of a reversible reaction
to "unmake" the PET again. That is why those particular
materials are selected. EG is an input into making PET,
and having some leftovers of it when making PET, would be
part of the output mixture. And then this gadget is
reversing the reaction.

Paul

Paul

2025-02-27 23:23:37 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

OK - belay that. The actual substrate seems to be mineral only, no organics.
The glycolaldehyde and the formate appear to be outputs, not inputs.

I can suggest this much.

It's a Redox reaction.

There are two equations, one is a reduction, one is an oxidation.

The PET and Ethylene Glycol is an attempt to clean up an industrial
pollutant, via using it as part of a half reaction. The "value added chemical"
notion, is the outputs are somehow easier to deal with. The glycol aldehyde dimer
is supposed to be a simple sugar.

In normal chemistry notation, one of the reactions
contributes something to the other reaction.

But attempts to get anything to balance, to have a net H2 output
for the Syngas, haven't worked out for me. Normally, you would
need some H2 to make a Syngas, but there is no source of gaseous H2
in the chamber.

The next stage after the making of Syngas, might be
something like this. This could make longer chain hydrocarbons
which are easier to store on site. Perhaps in a liquid form.
The industrial version of this, needs energy input. Looking
for a photochemsitry version, is to harvest the energy from the Sun.

"Photo-driven Fischer–Tropsch"

https://pubs.rsc.org/en/content/articlelanding/2020/ta/d0ta09097b

After reading several papers today, my conclusion is that everyone
is sloppy when writing these papers.

Paul

Jeff Layman

2025-02-28 11:02:32 UTC

Post by Paul

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U Unit"
(light red) is shown as containing hydrogen as it has green dots. Where
does that hydrogen come from? In Fig1.a the "CO2U Unit" is not shown as
containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

OK - belay that. The actual substrate seems to be mineral only, no organics.
The glycolaldehyde and the formate appear to be outputs, not inputs.

I can suggest this much.
It's a Redox reaction.
There are two equations, one is a reduction, one is an oxidation.
The PET and Ethylene Glycol is an attempt to clean up an industrial
pollutant, via using it as part of a half reaction. The "value added chemical"
notion, is the outputs are somehow easier to deal with. The glycol aldehyde dimer
is supposed to be a simple sugar.
In normal chemistry notation, one of the reactions
contributes something to the other reaction.
But attempts to get anything to balance, to have a net H2 output
for the Syngas, haven't worked out for me. Normally, you would
need some H2 to make a Syngas, but there is no source of gaseous H2
in the chamber.
The next stage after the making of Syngas, might be
something like this. This could make longer chain hydrocarbons
which are easier to store on site. Perhaps in a liquid form.
The industrial version of this, needs energy input. Looking
for a photochemsitry version, is to harvest the energy from the Sun.
"Photo-driven Fischer–Tropsch"
https://pubs.rsc.org/en/content/articlelanding/2020/ta/d0ta09097b
After reading several papers today, my conclusion is that everyone
is sloppy when writing these papers.

I'm replying to this, your other comments, and Nib's comment. I think
your bottom line above says it all! Is this the sort of quality we can
expect from one of the most prestigious scientific journals these days?

I'd noticed the pet mentioned, but it seemed to be a minor part of
things as the article appeared to be about CO2 capture more than
anything else. Oddly, they refer in the abstract to depolymerised pet's
use in a "counter-reaction", but they haven't previously referred to the
specific "reaction" which it is countering! BICBW and just missed it.
One interesting thing is the method of turning waste PET into a suitable
reducing agent (at the end of the section "Moist-bed gas-phase CO2
photoreduction procedure in flow"). They shred it, mix it with methanol
and THF, add KOH, and stir for 24 hours at 60°C. Or it's dissolved in
ethylene glycol (a by-product of the previous reaction) and reacted with
KOH at 150°C for 4 hours.

According to that section the efficiency is 60%, and the methanol and
THF are recovered by vacuum distillation, as is the ethylene glycol. But
that's still a lot of energy required. And I wonder what the efficiency
would be on an industrial scale. It's amazing how things don't scale up
or down the way they do in the lab!

--
Jeff

Tim Streater

2025-02-28 16:32:30 UTC

Post by Jeff Layman
According to that section the efficiency is 60%, and the methanol and
THF are recovered by vacuum distillation, as is the ethylene glycol. But
that's still a lot of energy required. And I wonder what the efficiency
would be on an industrial scale. It's amazing how things don't scale up
or down the way they do in the lab!

This, of course, is the $64 trillion question.

--
Tim

Tim+

2025-02-28 17:25:34 UTC

Is this the new “cold fusion”, its main function being to separate gullible
investors from their money?

Tim

--
Please don't feed the trolls

Paul

2025-02-28 20:01:22 UTC

Post by Tim+

Is this the new “cold fusion”, its main function being to separate gullible
investors from their money?
Tim

Personal opinion, if this was a game of poker, they're overplaying their hand.

I think the paper makes perfect sense, if they had placed a "dummy" counter-reaction
in the picture, and had something innocuous used there. This would not distract
from the value of the paper, which is the catalyst design. Other scientists
using their materials, or citing them, will be citing them for the catalyst.

They could have put a couple lines in their "for future work" section,
a thing about PET recycling being a possible counter reaction, assuming
ways and means are available to prepare the substance at low cost. Leaving
it as a challenge to other scientists to think up a digestive method.
Playing out their own digestive method, in the middle of a paper with
a limited page count, that's cheeky. I realize you get extra points
for making "an entire black box" as a solution, but that's not how
we beat CO2. CO2 is a collaborative effort. It will require the
best bits and pieces from a number of publications (because of course
there would be resistance to any large scale deployment, and every
amateur scientist alive would have rude things to say about the details).
when it is deployed in multiple countries, some of the starting materials
may not be available, and so substitute donor reactions may be needed.

We've already seen some tiny "test installs" for CO2 handling, and
already there is a lot of laughter. There is much more to this
than just lab work, there is public perception to deal with.

Paul

The Natural Philosopher

2025-03-01 03:23:21 UTC

Post by Tim+

Is this the new “cold fusion”, its main function being to separate gullible
investors from their money?
Tim

All 'green initiatives' are that...
Many years ago I attended a conference hosted by some financial people
to make investors aware of the opportunities.
We had hydrogen, renewable energy, battery technology, carbon capture,
biofuels - the lot.

I asked a few questions but wasn't overly impressed. I was there as a
technical representative of some financial people.

Juts as I was getting to guzzle the sandwiches, I was approached by two
German bankers.
"You seem to understand this: I haf one question. Is any of this
profitable without the government money ja?"
I thought about each presentation.
"No. It isn't"
"Ach then to London we go back. Ve haf been here before, the government
gives, so ve give, then ve make profit and the government stops giving,
and we lose money."

To be honest that is the best description of EcoBollox and GreenCrap I
ever heard.

--
“Those who can make you believe absurdities, can make you commit
atrocities.”

― Voltaire, Questions sur les Miracles à M. Claparede, Professeur de
Théologie à Genève, par un Proposant: Ou Extrait de Diverses Lettres de
M. de Voltaire

nib

2025-02-27 19:38:40 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-
new-
breakthrough-in-clean-energy/

Why not use plants instead?

Plants take a lot of effort and inputs (land, fertiliser, water) to grow.
Then you need to process them into something useful.
Being able to skip those steps has a lot of advantages. At the end of the
day it's all about efficiency numbers - remains to be seen how far this
could go in efficiency terms, and whether there are cases where it would
make sense where you don't have those inputs.
https://www.nature.com/articles/s41560-025-01714-y

I seem to be misunderstanding something in that article. Syngas is a
mixture of carbon monoxide and hydrogen. Where does the hydrogen come
from? Fig.1a shows just air entering the reaction chamber. There is no
mention of hydrogen at all (no green dots).
Fig1.b shows Air/N2 entering the reaction chamber. The "CO2U
Unit" (light red) is shown as containing hydrogen as it has green dots.
Where does that hydrogen come from? In Fig1.a the "CO2U Unit" is not
shown as containing any hydrogen.
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?
Any clarification gratefully received.

I does seem to mention the use of waste PET as one input. That will have
hydrogen in it?

nib

The Natural Philosopher

2025-02-28 09:30:33 UTC

Post by Jeff Layman
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?
Any clarification gratefully received.

It's Ecobollox. It's done by Magic.

--
"I am inclined to tell the truth and dislike people who lie consistently.
This makes me unfit for the company of people of a Left persuasion, and
all women"

Andy Burns

2025-02-28 13:43:50 UTC

Post by Jeff Layman
CO2 + 2H+ --> CO + H2 (H2O)
What does the 2H+ signify on the LHS of the equation? What does the H2O
in brackets mean?

H+ is a hydrogen ion, an atom that's lost an electron.

That chemical equation doesn't seem balanced

CO2 + 2H+ ==> CO + H2 (H2O)

1C 2O 2H+ ==> 1C 1O 2H 2H 1O

1C 2O 2H+ ==> 1C 2O 4H

Two hydrogens and two electrons have come from "somewhere", possibly UV
from the sunlight is knocking electrons off the titanium dioxide, but
it's still unbalanced.

Tim Streater

2025-02-27 12:41:15 UTC

On 27 Feb 2025 at 11:24:22 GMT, "The Natural Philosopher"

<https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-breakthrough-in-clean-energy/>

Why not use plants instead?

Maybe it's easier to capture the product. But following the link to their
report in Nature, it looks like they are using some exotic substrates for the
reaction (seems syngas is some mixture of hydrogen and carbon monoxide) but it
might be a way to use waste plastic.

--
Tim

SteveW

2025-02-27 13:01:54 UTC

Post by Tim Streater
On 27 Feb 2025 at 11:24:22 GMT, "The Natural Philosopher"

<https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-breakthrough-in-clean-energy/>

Why not use plants instead?

When I came across syngas, it was to be the product of burning municipal
waste in a plasma arc. The syngas first went to a heat exchanger to boil
water and drive a steam turbine, then through a second heat exchanger to
drive a lower pressure steam turbine, before being burnt for two gas
turbines and those waste gases passed through another heat exchanger to
pre-heat water for the other systems. All the turbines were to generate
electricity, some of which was to be used to power conveyors, a
shredder, pumps, the arc and the control system, with the rest exported
to the grid. I left before build started, so I don't know how it went.

alan_m

2025-02-27 12:25:32 UTC

Post by Jethro_uk
https://eastangliabylines.co.uk/science/sunlight-to-fuel-cambridges-new-
breakthrough-in-clean-energy/

Quote
"Carbon Capture and Storage (CCS) has been touted as a possible solution
to the climate crisis, and has recently received £22bn in funding from
the UK government."
/Quote

Stop this £22bn funding nonsense and the government can reverse all
those measures in the last budget that are predicted to add
significantly to the cost of our food, and other, bills.

Or is this just some more journalistic bullshit?

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

Paul

2025-02-27 17:49:14 UTC