Xue Yang, Lin Changqing, Zhong Jiancheng, Huang Dan, Persson Clas
Guangxi Novel Battery Materials Research Center of Engineering Technology, State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, School of Physical Science and Technology, Guangxi University, Nanning 530004, China.
Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China.
Phys Chem Chem Phys. 2024 Mar 6;26(10):8380-8389. doi: 10.1039/d3cp05824g.
The quest for high-performance solar cell absorbers has garnered significant attention in the field of photovoltaic research in recent years. To overcome the Shockley-Queisser (SQ) limit of ∼31% for single junction solar cell and realize higher power conversion efficiency, the concept of an intermediate band solar cell (IBSC) has been proposed. This involves the incorporation of an intermediate band (IB) to assist the three band-edge absorptions within the single absorber layer. BaSnS has an appropriate width of its forbidden gap in order to host an IB. In this work, doping of BaSnS was studied based on hybrid functional calculations. The results demonstrated that isolated and half-filled IBs were generated with suitable energy states in the band gap region after group-IIIA element (, Al, Ga, and In) doping at Sn site. The theoretical efficiencies under one sun illumination of 39.0%, 44.3%, and 39.7% were obtained for 25% doping concentration of Al, Ga, and In, respectively; thus, larger than the single-junction SQ-limit. Furthermore, the dopants have lower formation energies when substituting the Sn site compare to occupying the Ba and S sites, and that helps realizing a proper IB with three band-edge absorptions. Therefore, group-IIIA element doped BaSnS is proposed as a high-efficiency absorber for IBSC.
近年来，对高性能太阳能电池吸收体的探索在光伏研究领域引起了广泛关注。为了克服单结太阳能电池约31%的肖克利-奎塞尔（SQ）极限并实现更高的功率转换效率，人们提出了中间带太阳能电池（IBSC）的概念。这涉及引入一个中间带（IB）来辅助单吸收层内的三个带边吸收。BaSnS具有合适的禁带宽度以容纳一个IB。在这项工作中，基于杂化泛函计算研究了BaSnS的掺杂情况。结果表明，在Sn位点进行IIIA族元素（B、Al、Ga和In）掺杂后，在带隙区域产生了具有合适能态的孤立且半填充的IB。对于25%的Al、Ga和In掺杂浓度，在一个太阳光照下的理论效率分别为39.0%、44.3%和39.7%；因此，高于单结SQ极限。此外，与占据Ba和S位点相比，掺杂剂在替代Sn位点时具有更低的形成能，这有助于实现具有三个带边吸收的合适IB。因此，提出IIIA族元素掺杂的BaSnS作为IBSC的高效吸收体。
