SYDNEY, Jan. 20 (Xinhua) -- Researchers in Australia have set a world record for the efficiency of a new type of solar cell, marking a key step toward cheaper, more efficient and more durable solar technology.
The research team at Australia's University of New South Wales (UNSW) has improved the performance of solar cells made from antimony chalcogenide, an emerging photovoltaic material regarded as a strong candidate for next-generation solar technology, said a UNSW statement on Tuesday.
Their work, published in Nature Energy, has achieved a certified power conversion efficiency of 10.7 percent, the highest independently verified performance for this material to date, it said, adding the breakthrough has earned antimony chalcogenide its first entry in the international Solar Cell Efficiency Tables, which track record-setting results worldwide.
Next-generation solar panels use tandem cells, stacking two or more layers where each absorbs different sunlight parts for more electricity, said Scientia Professor Hao Xiaojing from UNSW's School of Photovoltaic and Renewable Energy Engineering (SPREE), who led the research.
Researchers seek optimal top-cell materials to pair with silicon, and antimony chalcogenide, made from abundant, stable and low-cost elements, shows strong promise due to its properties, with emerging applications such as transparent solar windows and indoor energy-harvesting devices, the statement said.
The UNSW researchers identified that the uneven distribution of sulfur and selenium in earlier cells created an "energy barrier" hindering the electrical charge generated by the sunlight to move through the solar cell.
"When the distribution of the elements inside the cell is more even, then the charge can move more easily through the absorber rather than being trapped before they are collected, which means more sunlight is converted into electricity," said the study's first author Chen Qian, a SPREE postdoctoral fellow.
By introducing a small amount of sodium sulfide during production, they stabilized the chemical reactions that form the solar-absorbing layer, and boosted efficiency beyond previous limits, the researchers said. ■