Transistor Made of Wood | Hacker News Reader

Transistor Made of Wood

pnas.org

97 pointstlubinski22 comments

Transistor made of *electron-ion conducting polymer* mixed with wood:

"The CW is prepared using a two-step strategy of wood delignification followed by wood amalgamation with a mixed electron-ion conducting polymer, poly(3,4-ethylenedioxythiophene)–polystyrene sulfonate (PEDOT:PSS)."

Similar to the "transparent wood!" story that made rounds a while back, where they took the wood out of the wood and replaced it with transparent plastic. Incredibly dishonest.

Here's a YouTube link to anyone curious about transparent wood: https://youtu.be/uUU3jW7Y9Ak

I don't know if I agree with it being "incredibly dishonest" - I think it's a bit misleading (like most popular science), but it comes from a place of wanting to get clicks/ be more mass-appeal, rather than to actually deceive.

Honesty is about honestly broadcasting the extent of your beliefs as much as it is expressing your true beliefs. If you fake a naivete and then lean into that to get clicks, you're still being dishonest.

Right. Once you take the lignite out of wood, you have a porous structure into which you can put other liquids. There are other variations on this theme - super strong wood, conductive wood, etc.[1] Some of those tricks work on cellulose agricultural waste.

Probably the most useful idea in this direction is oriented-strand board from bagasse, the long strands left after sugar is remove from sugar cane. Layers oriented in different directions are glued together, like plywood, to make something like particleboard, but with better tensile strength. It's a low-end composite material.

[1] https://www.scientificamerican.com/article/stronger-than-ste...

Is that product commercially available at low prices? Regular OSB took a while for me to understand but now that I do it's used in all sorts of stuff I build. It's cheap and much more dimensional than lumber, which often has a slight warp to it.

It used to be sold on a large scale by Cellotex. That company also sold asbestos board and went bankrupt due to liabilities from the asbestos business. Some company called Knight LLC ended up with the board business, but they seem to have gone bankrupt in 2010.

You certainly meant to write „lignin“ there. (Lignite is a type of coal).

Right. Having seen both materials in large quantities, I know.

So if the ship's planks were replaced by carbon fibre and the ropes by composites, is it not the same ship?

It’s the same ship except it’s not a wooden vessel anymore.

Would you read a paper on "wood coated transistors" ? :-)

I completely agree that the phrasing of the topic is misleading at best. However, the paper does add to the growing body of work on "organic" electronics. The journey of organic LEDs from concept to product is, to me, an interesting corollary. How much "metal" can you remove from electronics? How many of the elements that make electronics "toxic"? How many of the properties of the underlying organic base can you retain while still having a signal carrying capacity?

As an example;

E-"paper", made from cellulose hosted transistors, that are configured not to "switch" but to change the chemical composition of a "pixel" that changes is light absorption characteristics (and thus its "color" with respect to non-activated pixels.

Clearly a sci-fi "dream" or construction at this point, but understanding how to make cellulose a conductor while retaining the ability to make it into paper is a step toward possible realization of such an idea.

The bottom line for me is that "organic" electronics is one of those black swan type ideas that could really change a lot of things. So I collect papers like this one to track what people with time to research the questions find out. :-)

> wood coated transistors

Definitely a market for those with the audiophool crowd.

> Wood delignification

For those of you who are not up to speed on your Latin, the Saxon version of this word would be "unwooding".

So is this like taking a chunk of wood out of the piece of wood by cutting a hole in it so you get a window (which is both wooden and, technically, transparent, well, mostly), or like taking a piece of wood and then running it through a chain of chemical reactions ending up with some transparent substance which, in its chemical structure, may not even resemble wood at all?

There was an avenue of organ cloning being researched a few years ago. The idea was to treat all available organs as substandard (in that if it's not yours, you're buying time while you fight organ rejection for the rest of your days).

I bring it up here because it was a lot like delignification. Printing organs doesn't really work, but what if we took a random liver, removed all of the organic matter except the collagen, and then introduced a small sample of your cells into that collagen. Can we get it to grow into a functioning organ that is completely genetically compatible with you? The answer was 'maybe'.

Or perhaps a little less fanciful, delignification is kind of a bit like organic aerogel. Aerogel is a foam of two substances and we remove one. We are limited in the structures that can be produced. Pore size and variability and such.

Meanwhile we can an inferior carbon aerogel out of wood that has enough surface to volume ratio to work as a capacitor. And if we make them out of bamboo, they work even better. Do other plants have a better structure? Can we use nature or nurture to tune that? (eg, consistent water/nutrients, or cyclical?).

The best wine comes from mature grapes suffering through a dry spell.

Yeah, anytime someone applies "delignification" to wood, you're left with rayon (synthetic cotton). Then they added polymers back. So it's like they mixed some plastic and some cotton together and called it wood.

Supercapacitors are made of charcoal, and it looks like charcoal is mainly lignin, so the exact opposite.

I was suddenly picturing a sleek gamer desktop with unsubtle RGB lighting and acrylic panels highlighting sumptuous walnut veneers on the motherboard, cabling insulated with the smoothest silk, and a delicate aroma of apple pipe tobacco emanating from the heat sink.

This is interesting; maybe the "organic semiconductors" that Jan Hendrik Schön was working on were plausible.

The FTIR data is far from convincing (wrt the wood-PEDOT:PSS interaction), but cool demo.

Bra jobbat, Isak!

Very nice. Looks to be more of a FET.

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