单原子层二维材料是有潜力的太阳能光伏电池材料。研究基于二维材料的具有简单平面结构的太阳能吸收器的吸收率能否达到100%。提出二维材料/透明材料/金属基底结构，引入透明材料厚度和入射角度2个可调参数，因而能满足增强平面薄膜结构吸收率的2个维度的相位匹配条件。以MoS2和石墨烯为例，研究表明一定存在一对透明材料厚度值和入射角度值，使结构吸收率达到100%。平面结构加工简单，利于推广二维材料在光伏转换中的应用。
Monolayer two-dimensional (2D) materials hold promise for solar photovoltaics. This work investigated whether the 100% absorption could be achieved by 2D material solar absorbers with simple planar structure. The absorber was designed to consist of a 2D material film on top of a transparent layer coated on metallic substrate. The two-dimensional condition for perfect absorption can be satisfied by adjusting the transparent layer thickness and the incident angle. The results for the MoS2 and graphene absorbers show that there always exist a pair of transparent layer thickness value and incident angle value at which these absorbers achieve the 100% absorption. In addition, these absorbers can be easily fabricated, and thus they pave the way to efficient 2D material photovoltaic devices.
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