•A key phase transition intermediate (8H phase) was isolated and identified•Complete evolution of FAPbX3 by the 8H single crystal is provided•Effects doping anions cations on stabilization are revealed•Rational design for fabrication highly efficient stable PSCs suggested The stability formamidinium lead halide (FAPbX3) perovskites crucial to long-term perovskite solar cells, while a molecular-...

Mercury is present in the world in very small amounts, but it has played a very important role in the development of alchemy, extraction of gold and silver, in the chloro-alkali industry, batteries, construction of scientific instruments, treatment of illnesses, and pest control. Increasing environmental concerns are leading to a significant reduction in annual production and to its substitutio...