In this video we show how to make a dye sensitized solar cell based on titanium dioxide and anthocyanin found in raspberries. First get some titanium dioxide (anatase structure), about 0.5g will do. Then mix it with drops of vinegar until it has the consistency of thin paint or liquid corrector fluid. Add a drop of dishwashing detergent. This is to make it stick to the glass. Now get a piece of indium tin oxide glass. The indium tin oxide glass was purchased from delta technologies http://www.delta-technologies.com/ using a multimeter set to measure resistance, find the conductive side by measuring the resistance of the glass. The side that's conductive will have a much lower resistance than the non-conductive side. Tape the glass on three sides onto a flat surface, conductive side up. there should be able 5mm of tape on each edge. The tape will serve as a spacer guide for the titanium dioxide. Now using a glass rod, apply the titanium dioxide paint to the conductive of the indium tin oxide glass. Slide the rod across the tape so that it smears the paint evenly and smoothly across the glass. If the paint leaves streaks, you need to add more vinegar and try again. It should go on with a smooth coat. Now let the slide dry on air. Then carefully peel off the tape and get the slide. Use a damp cloth to clean off any excess titanium dioxide that might have oozed around behind the slide or off the edges. Place the slide, conductive side up, on a hot-plate and heat to 200+ celsius (preferably 550 celsius). The detergent and the vinegar will burn away and bake together the particles of titanium dioxide so that they stick to the glass. At first it will turn yellow and then turn light again as this happens. The whole process takes about 20 minutes. As that happens, get some fresh raspberries (juice made from artificial flavoring cannot be used) and crush them. Now get the cooled titanium dioxide slide and pour a few drops of the raspberry juice onto it. Be careful not to damage the titanium dioxide. Let it sit for a few minutes so the anthocyanin dyes absorb into the titanium dioxide. Then carefully pour water and alcohol over the slide to wash away raspberry bits and other chemicals we don't need. Let the slide dry. Take another indium tin oxide glass slide and pass the conductive side through a candle flame several times. This will build up a layer of soot that we need to catalyze the redox shuttle. Carefully wipe away the excess soot from the edges so that they match with the titanium dioxide from the slide. Now we make the redox shuttle and electrolyte by mixing 127mg of iodine crystals with 830mg of potassium iodide and 10mL ethylene glycol. Mix thoroughly until completely dissolved. Place a few drops of the redox shuttle and electrolyte onto the titanium dioxide and place over it the soot covered slide. The coated sides must be facing each other. Be sure to offset the slides so that you can access the conductive sides of both. Bind the slides together using binder clips. And that's done. the positive side is the soot covered slide, while the negative side is the titanium dioxide slide. Use alligator clips to contact the exposed sides. The titanium dioxide (anatase type) and potassium iodide and iodine were purchased from Alfa Aesar. http://www.alfa.com
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Acid-Compatible Halide Perovskite Photocathodes Utilizing Atomic Layer Deposited TiO2 for Solar-Driven Hydrogen Evolution. In Soo Kim et al (2018), ACS Energy Letters https://doi.org/10.1021/acsenergylett.8b01661 Although solution-processable halide perovskite semiconductors exhibit optoelectronic performance comparable to the best photoabsorbers for solar fuel production, halide perovskites rapidly decompose in the presence of water or even humid air. We show that a hybrid electron transport layer, a PC61BM + TiO2 film (18–40 nm thickness) grown over the sensitive absorber by atomic layer deposition, enables photoassisted proton reduction without further encapsulation. These semitransparent photocathodes, when paired with a Pt catalyst, display continuous reduction of H+ to H2 for hours under illumination, even while in direct contact with a strongly acidic aqueous electrolyte (0.5 M H2SO4). Under 0.5 Sun illumination, a photocurrent density of ~10 mA cm–2 is observed, and a photovoltage of 0.68 V assists proton reduction, consistent with a structurally related photovoltaic (PV) device. Submersible halide perovskite photoelectrodes point the way to more efficient photoassisted overall water splitting and other solar fuel generation using solution-processed semiconductors with tunable band gaps.
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Download Now: http://tinyurl.com/thesolarproject Without a solar panel you are losing a lot of money but no more after you've downloaded this video. Today meet Michael Harvey who saved $14,400 by building his own solar panel to power his whole household from scratch. If you love to enjoy freedom from paying huge bills then this solar project is your only shot at getting your true freedom. 8 videos with step by step guides are available for download right away. Get videos: http://tinyurl.com/thesolarproject Step by step video on how to build your own solar panel was found here: https://www.youtube.com/watch?v=mv5AqYKTPfU
Views: 297 Samuel Oppong
Provost's Faculty Lecture Series: Building Intellectual Community February 10, 2016 Professor Nitin P. Padture, Ph. D Director, Institute for Molecular & Nanoscale Innovation Professor Padture presents exciting research on a new type of solar cell (photovoltaic) based on ‘perovskite’ materials offering hope for the efficient and inexpensive generation of solar power, together with a discussion of challenges and opportunities.
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21st-century materials science is now making possible a world where buildings harvest their own energy, bridges repair themselves, clothes increase life expectancy by monitoring health. But many alternative realities are possible, each driven by different cultural and economic forces. We could find ourselves dealing with seas full of plastic, declining life expectancy, and energy black-outs. Which future will we choose? In this lecture, Professor Mark Miodownik argues that only a deeper understanding of materials science will allow us to navigate the future successfully. Professor Miodownik is a best-selling author, broadcaster, and innovative thinker who has been bringing new ideas in materials science to the general public for decades. His many awards and honors include the Communication Awards of the National Academics of Sciences, Engineering, and Medicine.
Views: 297 MIT Materials Science and Engineering (DMSE)
Titanium dioxide, also known as titanium(IV) oxide or titania, is the naturally occurring oxide of titanium, chemical formula TiO 2. When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. Generally it is sourced from ilmenite, rutile and anatase. It has a wide range of applications, from paint to sunscreen to food colouring. When used as a food colouring, it has E number E171. This video is targeted to blind users. Attribution: Article text available under CC-BY-SA Creative Commons image source in video
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Investor Systems Managing Director Carl Capolingua appears on Sky Business Your Money Your Call on 25th November 2015. In the show he discusses the ASX market outlook for remainder of 2015 (1:16), Federal Reserve activity into 2016 (5:05), Nick Scali (NCK) (8:20), Flexigroup (FXL) (12:45), Programmed Maintenance Services (PRG) (14:00), IT sector top picks (E-Merchants (EML), HUB24 (HUB), Vocus Communications (VOC) & agricultural sector top pick (Ridley Corporation (RIC)) (16:45), Transurban Group (TCL) (20:58), Santos (STO) and explanation of technical term "Dead Cat Bounce" (27:34), Macquarie Atlas Roads (MQA) (29:50), Tox Free (TOX) (32.40), Slater & Gordon (SGH) (37:15), infant formula stocks (A2 Milk (A2M), Bellamy's (BAL), Bega Cheese (BGA)) (42:05), Rent.com (RNT) (49:40), Yowie Group (YOW) (53:50), aged care stocks (Estia Health (EHE), Ramsay Healthcare (RHC), Japara Healthcare (JHC), Cochlear (COH), alternatives to AMP (Magellan Flagship Fund (MFF)) (57:50), Woodside Petroleum (WPL), Medibank Private (MPL) and yield plays (1:02:15), Netcomm Wireless (NTC) & Mobile Embrace (MBE) (1:05:05), BHP (1:08:48).
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This is an audio version of the Wikipedia Article: Selenium 00:01:54 1 Characteristics 00:02:03 1.1 Physical properties 00:04:22 1.2 Optical properties 00:04:43 1.3 Isotopes 00:05:03 2 Chemical compounds 00:05:21 2.1 Chalcogen compounds 00:07:49 2.2 Halogen compounds 00:08:59 2.3 Selenides 00:10:07 2.4 Other compounds 00:10:42 2.5 Organoselenium compounds 00:11:48 3 History 00:14:46 4 Occurrence 00:16:19 5 Production 00:18:40 6 Applications 00:18:49 6.1 Manganese electrolysis 00:19:17 6.2 Glass production 00:19:53 6.3 Alloys 00:20:31 6.4 Lithium–selenium batteries 00:20:55 6.5 Solar cells 00:21:09 6.6 Photoconductors 00:21:34 6.7 Rectifiers 00:21:51 6.8 Other uses 00:23:52 7 Biological role 00:26:29 7.1 Evolution in biology 00:29:31 7.2 Nutritional sources of selenium 00:30:34 7.3 Indicator plant species 00:31:05 7.4 Detection in biological fluids 00:31:53 7.5 Toxicity 00:36:04 7.6 Deficiency 00:36:31 7.7 Controversial health effects 00:37:37 8 See also Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago. Learning by listening is a great way to: - increases imagination and understanding - improves your listening skills - improves your own spoken accent - learn while on the move - reduce eye strain Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone. You can find other Wikipedia audio articles too at: https://www.youtube.com/channel/UCuKfABj2eGyjH3ntPxp4YeQ You can upload your own Wikipedia articles through: https://github.com/nodef/wikipedia-tts "The only true wisdom is in knowing you know nothing." - Socrates SUMMARY ======= Selenium is a chemical element with symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium (from Ancient Greek σελήνη (selḗnē) "Moon") was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in metal sulfide ores, where it partially replaces the sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during production. Minerals that are pure selenide or selenate compounds are known but rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been mostly replaced with silicon semiconductor devices. Selenium is still used in a few types of DC power surge protectors and one type of fluorescent quantum dot. Selenium salts are toxic in large amounts, but trace amounts are necessary for cellular function in many organisms, including all animals. Selenium is an ingredient in many multivitamins and other dietary supplements, including infant formula. It is a component of the antioxidant enzymes glutathione peroxidase and thioredoxin reductase (which indirectly reduce certain oxidized molecules in animals and some plants). It is also found in three deiodinase enzymes, which convert one thyroid hormone to another. Selenium requirements in plants differ by species, with some plants requiring relatively large amounts and others apparently requiring none.
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Views: 39 Amy Shang