Liu Shaoting, Hao Yang, Sun Mengxue, Ren Jingkun, Li Shiqi, Wu Yukun, Sun Qinjun, Hao Yuying
College of Physics, College of Electronic Information and Optical Engineering, Key Lab of Advanced Transducers and Intelligent Control System, Taiyuan University of Technology, Taiyuan, 030024, China.
Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan, 030000, China.
Small. 2024 Sep;20(38):e2402385. doi: 10.1002/smll.202402385. Epub 2024 May 14.
Non-radiative recombination losses limit the property of perovskite solar cells (PSCs). Here, a synergistic strategy of SnSeQDs doping into SnO and chlorhexidine acetate (CA) coating on the surface of perovskite is proposed. The introduction of 2D SnSeQDs reduces the oxygen vacancy defects and increases the carrier mobility of SnO. The optimized SnO as a buried interface obviously improves the crystallization quality of perovskite. The CA containing abundant active sites of ─NH/─NH─, ─C═N, CO, ─Cl groups passivate the defects on the surface and grain boundary of perovskite. The alkyl chain of CA also improves the hydrophobicity of perovskite. Moreover, the synergism of SnSeQDs and CA releases the residual stress and regulates the energy level arrangement at the top and bottom interface of perovskite. Benefiting from these advantages, the bulk and interface non-radiative recombination loss is greatly suppressed and thereby increases the carrier transport and extraction in devices. As a result, the best power conversion efficiency (PCE) of 23.41% for rigid PSCs and the best PCE of 21.84% for flexible PSCs are reached. The rigid PSC maintains 89% of initial efficiency after storing nitrogen for 3100 h. The flexible PSCs retain 87% of the initial PCE after 5000 bending cycles at a bending radius of 5 mm.
非辐射复合损失限制了钙钛矿太阳能电池（PSC）的性能。在此，提出了一种将SnSe量子点（QDs）掺杂到SnO中并在钙钛矿表面进行醋酸氯己定（CA）包覆的协同策略。二维SnSe量子点的引入减少了氧空位缺陷，提高了SnO的载流子迁移率。优化后的SnO作为埋入界面显著提高了钙钛矿的结晶质量。含有丰富─NH/─NH─、─C═N、CO、─Cl基团活性位点的CA钝化了钙钛矿表面和晶界的缺陷。CA的烷基链还提高了钙钛矿的疏水性。此外，SnSe量子点和CA的协同作用释放了残余应力，调节了钙钛矿顶部和底部界面的能级排列。受益于这些优势，体相和界面的非辐射复合损失得到了极大抑制，从而增加了器件中的载流子传输和提取。结果，刚性PSC的最佳功率转换效率（PCE）达到23.41%，柔性PSC的最佳PCE达到21.84%。刚性PSC在氮气中储存3100小时后保持初始效率的89%。柔性PSC在弯曲半径为5毫米的情况下经过5000次弯曲循环后保留初始PCE的87%。
