РОССИЙСКАЯ АКАДЕМИЯ НАУК

УРАЛЬСКОЕ ОТДЕЛЕНИЕ

ИНСТИТУТ ХИМИИ TBEPДОГО ТЕЛА
   
| | | | |
| | | |
 18.01.2011   Карта сайта     Language По-русски По-английски
Новые материалы
Экология
Электротехника и обработка материалов
Медицина
Статистика публикаци


18.01.2011



Size matters in piezoelectric materials



14 January 2011



Nanowires that produce current when bent and deformed can show huge improvements in efficiency as their diameters are shrunk. The findings will help advance research to power technology at the nanoscale.


Ravi Agrawal and Horacio Espinosa of Northwestern University in Illinois, US, have been investigating the properties of nanowires for several years: 'Nanowires are potential building blocks of future devices,' Espinosa explains. 'However, before the construction of devices that use millions of nanowires takes over, the fundamental properties of an individual nanowire must be fully understood.'


Recently scientists have shown that at the nanoscale, conversion of mechanical energy to electrical energy (so-called piezoelectricity) is much higher than in bulk materials. However, Espinosa noticed that those who had measured this property in nanowires reported widely differing results, so he decided to use a computational approach to find out what was actually being generated.



"Before the construction of devices that use millions of nanowires takes over, the fundamental properties of an individual nanowire must be fully understood"
- Horacio Espinosa of Northwestern University


Modelling gallium nitride and zinc oxide nanowires (known to be piezoelectric), Espinosa and Agrawal calculated that the piezoelectric coefficient of the wires can be improved two-fold if their diameter is reduced to less than 1nm, rather than 10s or 100s of nanometres that have been investigated in the past.  


For ZnO wires, the improvement in piezoelectric properties was limited to wires under 1.5nm in diameter, but GaN wires showed enhancement at diameters up to and over 2.5nm. 'We certainly expected a change, but maybe not that large,' says Espinosa. 


'This is an important result in guiding the research in nanogenerators and piezotronics' says Zhong Lin Wang of Georgia Institute of Technology, US, who first showed that zinc oxide nanowires could act as generators of electricity. He sees envisages future in which nanogenerators are used to power everything from implanted biosensors to mp3 players. 


'The results suggest that there is an advantage in reducing the size of the piezoelectric elements used in an energy harvester since the extracted electrical energy will be greater,' says Espinosa. Both Espinosa and Wang hope that the work will inspire the design of new devices using these materials and their properties. For Espinosa though, he will continue to focus on discovering new phenomena in nanowires and nanostructures. 


Laura Howes 



References


R Agrawal and H D Espinosa, Nano Lett.,  2011, DOI: 10.1021/nl104004



Дизайн и программирование N-Studio 
А Б В Г Д Е Ё Ж З И Й К Л М Н О П Р С Т У Ф Х Ц Ч Ш Щ Ъ Ы Ь Э Ю Я
  • Chen Wev .  honorary member of ISSC science council

  • Harton Vladislav Vadim  honorary member of ISSC science council

  • Lichtenstain Alexandr Iosif  honorary member of ISSC science council

  • Novikov Dimirtii Leonid  honorary member of ISSC science council

  • Yakushev Mikhail Vasilii  honorary member of ISSC science council

  • © 2004-2019 ИХТТ УрО РАН
    беременность, мода, красота, здоровье, диеты, женский журнал, здоровье детей, здоровье ребенка, красота и здоровье, жизнь и здоровье, секреты красоты, воспитание ребенка рождение ребенка,пол ребенка,воспитание ребенка,ребенок дошкольного возраста, дети дошкольного возраста,грудной ребенок,обучение ребенка,родить ребенка,загадки для детей,здоровье ребенка,зачатие ребенка,второй ребенок,определение пола ребенка,будущий ребенок медицина, клиники и больницы, болезни, врач, лечение, доктор, наркология, спид, вич, алкоголизм православные знакомства, православный сайт творчeства, православные рассказы, плохие мысли, православные психологи рождение ребенка,пол ребенка,воспитание ребенка,ребенок дошкольного возраста, дети дошкольного возраста,грудной ребенок,обучение ребенка,родить ребенка,загадки для детей,здоровье ребенка,зачатие ребенка,второй ребенок,определение пола ребенка,будущий ребенок