research & development
research & development
Perovskite solar cells hit new world efficiency record
They ’ re flexible , cheap to produce and simple to make – which is why perovskites are the hottest new material in solar cell design . And now , engineers at Australia ’ s University of New South Wales in Sydney have smashed the trendy new compound ’ s world efficiency record .
S peaking at the Asia-Pacific Solar Research Conference in Canberra on Friday 2 December , Anita Ho-Baillie , a senior research fellow at the Australian Centre for Advanced Photovoltaics ( ACAP ), announced that her team at UNSW has achieved the highest efficiency rating with the largest perovskite solar cells to date . The 12.1 per cent efficiency rating was for a 16 cm2 perovskite solar cell , the largest single perovskite photovoltaic cell certified with the highest energy conversion efficiency , and was independently confirmed by the international testing centre Newport Corp , in Bozeman , Montana . The new cell is at least 10 times bigger than the current certified high-efficiency perovskite solar cells on record .
Her team has also achieved an 18 per cent efficiency rating on a 1.2 cm2 single perovskite cell , and an 11.5 per cent for a 16 cm2 four-cell perovskite mini-module , both independently certified by Newport . “ This is a very hot area of research , with many teams competing to advance photovoltaic design ,” said Ho-Baillie . “ Perovskites came out of nowhere in 2009 , with an efficiency rating of 3.8 per cent , and have since grown in leaps and bounds . These results place UNSW amongst the best groups in the world producing state-of-the-art high-performance perovskite solar cells . And I think we can get to 24 per cent within a year or so .” Perovskite is a structured compound , where a hybrid organic-inorganic lead or tin halide-based material acts as the light-harvesting active layer . They are the fastest-advancing solar technology to date , and are attractive because the compound is cheap to produce and simple to manufacture , and can even be sprayed onto surfaces .
“ The versatility of solution deposition of perovskite makes it possible to spray-coat , print or paint on solar cells ,” said Ho-Baillie . “ The diversity of chemical compositions also allows cells be transparent , or made of different colours . Imagine being able to cover every surface of buildings , devices and cars with solar cells .”
Most of the world ’ s commercial solar cells are made from a refined , highly purified silicon crystal and , like the most efficient commercial silicon cells ( known as PERC cells and invented at UNSW ), need to be baked above 800 ° C in multiple high-temperature steps . Perovskites , on the other hand , are made at low temperatures and 200 times thinner than silicon cells .
But although perovskites hold much promise for cost-effecti`ve solar energy , they are currently prone to fluctuating temperatures and moisture , making them last only a few months without protection . Along with every other team in the world , Ho-Baillie ’ s is trying to extend its durability . Thanks to what engineers learned from more than 40 years of work with layered silicon , they ’ re are confident they can extend this . Nevertheless , there are many existing applications where even disposable low-cost , high-efficiency solar cells could be attractive , such as use in disaster response , device charging and lighting in electricity-poor regions of the world . Perovskite solar cells also have the highest power to weight ratio amongst viable photovoltaic technologies .
“ We will capitalise on the advantages of perovskites and continue to tackle issues important for commercialisation , like scaling to larger areas and improving cell durability ,” said Martin Green , Director of the ACAP and Ho- Baillie ’ s mentor
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EQ December 2016 www . EQMagPro . com