#rccrawler Little bit of evening moss Crawlin to end the weekend.
Peter Solarz
KIROKAZE
tumblr dot com

@theartofmadeline


blake kathryn
Xuebing Du
cherry valley forever
Mike Driver
RMH

PR's Tumblrdome
Alisa U Zemlji Chuda
Sade Olutola

pixel skylines
Lint Roller? I Barely Know Her
wallacepolsom

Product Placement
hello vonnie
trying on a metaphor
Misplaced Lens Cap

seen from United States
seen from Greece

seen from Malaysia

seen from China
seen from Lithuania

seen from United States
seen from United States

seen from United States
seen from Finland

seen from Ukraine

seen from Singapore
seen from United States
seen from Japan

seen from Türkiye

seen from United States
seen from Malaysia
seen from United States
seen from United States
seen from United States

seen from Türkiye
@ondray-c
#rccrawler Little bit of evening moss Crawlin to end the weekend.

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch • No registration required • HD streaming
Practicing the all important skill of kitten filming.
Also we tumblin again.
Spiro gets hot during combat. That battery temp was ok, but the smaller battery got too hot (70'C) so I didn't use it again.
Pretty colors on the underside of this Huntsman in Strickland State Forest.

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch • No registration required • HD streaming
This guy was roaming around Glenrock last night :-) the more I learn about trap doors and funnel webs the less confident I am in identifing them.
The news story in the Oxford Photovoltaics post is misleading, especially the caption describing the materials as "non-toxic". This is wrong; the cells are made with lead as well as the organic components. Lead-free perovskite solar isn't good yet. Of course, Oxford PV goes very far out of their way to downplay the lead content of their products; on their page they refer to lead iodide only as "yellow precursor salt" to confuse the public. Wikipedia has some useful info on perovskite solar.
I’ll admit that I was unaware of the fact that perovskike solar cells typically contain lead – 5 seconds on Google shows this to be true. However, Oxford Photovoltaics put out a press release in 2014 on lead-free perovskites, so they’ve clearly been working on this for some time.
Quoting:
“This is a hugely important breakthrough which could have a significant impact on the speed with which we can bring this important technology to market […] the elimination of lead will certainly reduce customer concerns over recyclability over the life of the product.”
– Kevin Arthur, Chief Executive
Still, I was curious. So I did some digging…
Oxford Photovoltaics apparently base their technology on the work of Henry Snaith, a professor at the University of Oxford. A quick check of his recent publications finds that he has indeed worked on lead halide perovskites. Unsurprisingly, given their prevalence in the field.
Though Snaith has also done a lot of work on substituting metals in the perovskite compounds (Klug et al, 2016), as well as on lead-free perovskites (Volonakis et al, 2016). Of particular interest, Sakai et al (2017) report a study on Cesium Bromopalladate (Cs₂PdBr₆), a non-toxic alternative. Given this compound is solution processable, which links with the fact that Oxford Photovoltaics’ solar glass is described as “printed”, I suspect this may be the compound which they’re employing.
Additionally, as I’m guessing you probably know, lead halide perovskites are killed pretty easily by water, so a window pane made from them wouldn’t last long – especially somewhere as damp as the UK! Cesium bromopalladate reportedly fixes this, as the compound is water resistant.
In my experience, what gets published by any given lab is typically a few years behind their current capability, especially where industry contracts are involved (proprietary periods can last a long time). The headline in my post was sourced from the Guardian (actually 4 years ago) and, quite frankly, making a false claim that something is non-toxic when it isn’t in front of an international audience like that would be tantamount to career suicide, as well as setting the whole industry back years. This all leads me to the logical conclusion that they aren’t using lead in their products.
Admittedly though, confirmation would need to come from Oxford Photovoltaics themselves. Perhaps I should send them an e-mail to ask…
Incidentally, while looking I found another article by Hoye et al (2017), on bismuth oxyiodide as a replacement for lead, which you might find interesting. Apparently, these bismuth-based photovoltaics are even more efficient than lead based ones.
That all turned into quite a rabbit hole, but it was very informative, so thanks for your comment!
@firebendinglemur
Ps: Putting the fun in density functional theory? Nice. 😉
I’m doing a PhD on Perovskite Solar Cells and was looking to see if there was any talk of them on Tumblr, there’s not much so I'll add to it. Most, (guessing 95%) of PSC work is using lead based blends. I’m working with lead based cells. Even the Oxford group, who I visited last Sep for a conference they hosted. They do some lead free work, but it’s not their focus. All the highest performing cells are using lead-halide blends. The lead in these cells does pose a risk, I believe it’s a manageable one. I’d never call them non-toxic though :) I don’t want to downplay it either - there’s a popular downplaying that the lead content of these cells (approx 2g per square m) is less than in the top 1cm of soil. Which is true in most city/suburban areas. But the lead in these cells is far more bio-available due to the presence of the organic cation. I will say I’ve been working with these cells for 2 years and my blood lead level has gone down - probably because I’m not working with greasy industrial equipment anymore. We get tested every 6 months to make sure we haven’t contaminated ourselves, and my levels are very low. What the lead content means it we definitely won’t see this technology in rooftop applications. Maybe not even in large solar fields, simply because silicon is cheap now and long lasting. Where we will see them is in areas where we want maximum power density, like electric car roofs or satellites. Perovskites have a very tunable adsorption spectrum, so they can pick up the UV and blue light and let through the red and infra-red to a silicon cell underneath - improving the overall efficiency, called a tandem cell. In these applications the lead content may be deemed worth the risk, where we don’t need the power density it won’t be worth the risk. The Bismuth Oxyiodide paper carefully avoided putting an efficiency in their abstract, their cells have about 1/4 the performance of a lead based one. I am still excited and hopeful for the lead free cells, even the 6% solar to electric efficiency they achieved is very usable if the cost of production is low. I do think we will see commercial lead based ones first though. In the thin film solar field there is an expectation for external certification of device performance so published efficiencies are pretty representative of what a lab is putting out. Efficiencies of large devices using industrially applicable methods are still low, but it’s improving rapidly! Hopefully I’ll get my first paper out in this area soon, if you’re interested I can let you know.
Bio-luminescent Mushrooms on the Minyon Falls walking track near Mullumbimby. I saw these on Boxing day (well boxing night) only a couple of days after the rain, so they were really tiny. Took my Mum and little sister :)
Friend: “What did you look at while you were in London?” Me: “Squirrels”
Big harvestman (I think) in the Beech forest at Gloucester tops. What a dickhead.

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch • No registration required • HD streaming
What did the necromancer say when he accidentally raised the wrong person? I’ve made a grave mistake.
I managed to find some bio-luminescent mushrooms before it got too cold :) This was out in the ancient Beech forest at Gloucester Tops. Excellent reward for the driving and crawling in mud :) They weren’t glowing real bright to the eye as it was a very moonlit night, but the camera was able to get their glow and some moonlit sheen.
Fluoro mushrooms in Watagan State forest.
Angle Headed Dragon (I think) in Chichester State forest NSW...If I didn’t stop to get the leaches off me I would have ran straight into it.
More fluoro millipedes!

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch • No registration required • HD streaming
A real big water huntsman (I think) in the Watagans.
An overlay of my multiple attempts at photographing fireflies in the Watagans.