Source: riken.jp
Hita-hrinkanleg tækni þróuð af allri-RIKEN teymi gæti gert kleift að festa sólarsellur og snertiskynjara við hluti sem gera þá krefjandi í lagskiptum1.
Recent studies have indicated that curved solar-cell panels capture sunlight more efficiently than flat ones on cloudy days. One way to produce curved electronics is with rubber-like substrates, but solar cells on such substrates usually have much lower performance. In contrast, solar cells fabricated on flexible sheets have high efficiency, but can be difficult to attach to curved surfaces —a fact that anyone who has tried to gift wrap a soccer ball can attest to.
Vísindamenn undir forystu Takao Someya frá RIKEN Center for Emergent Matter Science komust að því að hægt væri að vinna bug á þessu vandamáli með því að nota hita-minnkandi filmur, sem eru almennt notaðar til að umlykja vörur eins og-yfir{{2} } gegn lyfjum. Þó að flest raftæki séu of stíf eða viðkvæm til að vera fest við skreppafilmu, sérhæfir teymið sig í að framleiða ofurþunn tæki með einstaka eiginleika.
"When a material becomes thinner, it becomes more flexible—that's why we can crumple aluminum foil by hand, but can also use aluminum to make bicycles," explains postdoctoral researcher Steven Rich. "Although we use rigid materials such as metals and plastics, they are three times thinner than a grocery bag and can bend very sharply without breaking."
Rich and three RIKEN colleagues attached a non-stretchable but flexible polymer sheet to a shrink film, then used microscopy to observe the layered structure during various exposures to heat. These tests revealed that, as the device's area shrank by up to 70 percent , the ultrathin sheets relieved the strain of compression by forming tiny wrinkles and folds.
By controlling the size of these wrinkles and choosing materials capable of surviving both heat and severe wrinkling, the RIKEN team found they could shrink prefabricated organic photovoltaic modules onto round objects (Fig. 1) as well as ones with sharp angles and irregular curvatures, including plastic rocks and traditional Japanese Daruma dolls.
Þrátt fyrir að vísindamenn hafi gert ráð fyrir því að samdráttur gæti skemmt ljósaflsíhluti og dregið úr afköstum tækisins, þá gerðist hið gagnstæða. Tilraunir gáfu til kynna að ljóseiginleikar skreppa-framkalla hrukkubyggingar bættu ljósgleypni, aukið skilvirkni aflskipta um allt að 17 prósent miðað við slétt tæki.
The team also used shrink wrapping to laminate the handle of a teacup with an electronic touch sensor—a delicate feat that serves as an example of how this technology could be widely applied. "We could incorporate sensors along with displays, power-generation systems, and transistors to create interactive interfaces," Rich says.
