The presence of a defective layer composed of nanocrystals and amorphous regions at the surface of perovskite films has been shown to initialize the degradation of perovskites and cause nonradiative recombination. Here, we report the discovery that these defective surface layers are mechanically softer than the crystalline regions. The defective surface layer has a weaker bonding with the crystalline layer underneath it, which enables a facile approach to mechanically peel-off these defective layers using adhesive tapes. The chosen low-cost tape has an appropriate bonding force with perovskites, so the peeling does not damage the crystalline region and embedded interfaces underneath. The tape-treated devices retained 97.1% of the initial efficiency after operation at the near maximum power point under one sun illumination for 1,440 h at 65°C. This method is universally effective in enhancing the stability of various commonly used perovskite compositions and is compatible with the scaling up of perovskite solar modules.

已经显示在钙钛矿膜的表面上存在由纳米晶体和非晶区域组成的缺陷层会引发钙钛矿的降解并引起非辐射复合。在这里，我们报告发现这些缺陷表面层在机械上比晶体区域软。有缺陷的表面层与其下面的结晶层之间的结合力较弱，这使得使用胶带将这些有缺陷的层机械剥离的方法变得容易。所选的低成本胶带与钙钛矿具有适当的粘结力，因此剥离不会损坏结晶区域和下方的嵌入界面。经胶带处理的器件在接近最大功率点，在65°C的太阳光照下1,440 h下运行后，仍保持97.1％的初始效率。