A good way to maintain the long-term performance stability of perovskites solar cells

• In recent years, perovskite materials are rapidly becoming a popular candidate in the field of solar energy. However, one of its main disadvantages is that it is easily broken down in direct sunlight. The good news is that a research team at UCLA has just introduced a new coating for perovskite photovoltaic panels that improves its stability in sunlight.
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• photo (Source: UCLA / Shaun Tan)
  

• According to the article published in Nature recently, UCLA researchers have found the root cause of the problem and proposed simple application solutions that can be implemented in the manufacturing process.

  
  

  For a long time, silicon based materials have occupied a very high position in the field of solar cells, and few materials can compete with them in terms of efficiency, durability, cost, etc.

  
  

  However, in recent years, with the rise of metal halide research, perovskite is rapidly growing into a strong competitor to it - in addition to being close to silicon based materials in efficiency, it is also more lightweight, flexible, and low-cost.
  

  
  

  However, one of the major problems of perovskite materials is that they are easy to be decomposed under direct sunlight, so the efficiency will decrease with time.

  
  

  Previously, some researchers tried to add macromolecules, old pigments, carbon nano dots made of hair, two-dimensional additives, pepper compounds, and even quantum dot technology to try to save the durability of perovskite solar cells.

  
  

  Fortunately, the UCLA team has found the mechanism behind the decomposition of perovskite materials. Ironically, this phenomenon originated from the surface treatment process aimed at repairing defects and improving their efficiency.

  
  

  It is reported that this process involves coating the surface with a layer of organic ions, but the research team found the disadvantage of doing so - electrons carrying energy will gather on the surface of the perovskite photovoltaic panel.

  
  

  What's worse, this situation will in turn destroy the arrangement of perovskite atoms, and eventually lead to their decomposition over time.

  
  

  In view of this, UCLA team thought of adding positive and negative ion pairs to solve this problem in the surface treatment process.

  
  

  This will not only help to keep the surface neutral and stable, but also will not interfere with the original defect prevention treatment process.