Efficient kesterite solar cells with high open-circuit voltage for applications in powering distributed devices
Efficient kesterite solar cells with high open-circuit voltage for applications in powering distributed devices
复制标题
DOI：
10.1038/s41560-017-0028-5
复制
发表时间：
2017-11-01
期刊：
影响因子：
56.7
通讯作者：
Haight, Richard
中科院分区：
文献类型：
--
作者：
Antunez, Priscilla D.;Bishop, Douglas M.;Haight, Richard
同时实现薄膜太阳能电池的高电压和高效率对于实际应用至关重要。虽然由地球上储量丰富的黄锡锌矿吸收剂 Cu2ZnSn(SxSe(1-x))(4) 制成的太阳能电池提供了一种有吸引力的、无毒的能量收集解决方案，但其利用率受到相对较低的开路电压的限制，从而限制了效率。增加硫含量以加宽带隙可以提高电压，但通常会牺牲效率。在这里，我们报告了通过制造高硫含量的太阳能电池在这一基本问题上取得的重要进展，该电池的效率高达 11.89%，开路电压高达 670 mV。在多步骤过程中，功能齐全的太阳能电池与其生长基板分离，随后沉积高功函数背接触。通过这种方法，我们制造了一个串联器件，该器件在 1 个太阳照度下产生 5.7 V 电压，在低于 10(-3) 个太阳照度的低光照条件下产生类似于 2 V 的电压。
Simultaneously achieving high voltage and high efficiency in thin-film solar cells is of paramount importance for real-world applications. While solar cells fabricated from the Earth-abundant kesterite absorber Cu2ZnSn(SxSe(1-x))(4) provide an attractive, non-toxic, energy harvesting solution, their utilization has been constrained by relatively low open-circuit voltages that limit efficiency. Increasing the sulfur content to widen the bandgap boosts the voltage, but usually at the expense of efficiency. Here, we report important progress on this fundamental problem by fabricating solar cells with high sulfur content that exhibit efficiencies up to 11.89% with open-circuit voltages as high as 670 mV. In a multistep process, fully functional solar cells are separated from their growth substrate, and a high-work-function back contact is subsequently deposited. With this approach, we fabricated a series-connected device that produces 5.7 V under 1 Sun illumination and similar to 2 V under low lighting conditions, below 10(-3) Suns.