Herein, we reveal for the first time a comprehensive mechanism of poorly investigated electrochemical decomposition of CH3NH3PbI3 using a set of microscopy techniques (optical, AFM, PL) and ToF-SIMS. We demonstrate that applied electric bias induces the oxidation of I– to I2, which remains trapped in the film in the form of polyiodides, and hence, the process can be conceivably reversed by reduction. On the contrary, reduction of organic methylammonium cation produces volatile products, which leave the film and thus make the degradation irreversible. Our results lead to a paradigm change when considering design principles for improving the stability of complex lead halide materials as those featuring organic cations rather than halide anions as the most electric field-sensitive components. Suppressing the electrochemical degradation of complex lead halides represents a crucial challenge, which should be addressed in order to bring the operational stability of perovskite photovoltaics to commercially interesting benchmarks.

We systematically explored the photochemical stability of MAPbI3 interfaces with five different charge transport layers (CTLs): substituted naphthalene (NDI) and perylene (PDI) diimides, fullerene derivatives PC61BM and PC71BM, and spiro-OMeTAD.

A polyfunctional catalyst for hydrorefining of the catalytic naphtha cut with a high olefin content isproposed. This catalyst induces isomerization and hydrogenation of olefins on contact with the feedstock with formation of isoparaffins, isomerization of n-paraffins, hydrotreating to remove sulfur, and other processes. The naphtha obtained satisfies the Euro-4 standard (2005) with respect to quality.The proportion of thermal and catalytic cracking processes is steadily increasing in world oil refining. This is due to the increase in production of heavy crude and the necessity of conserving resources.A high olefin content (40-50%) that reduces the stability and performance indexes is characteristic of thermal and catalytic naphtha cuts. The quality of these cuts can be increased by catalytic hydrorefining, which reduces the olefin and sulfur content.Severe requirements are imposed on the quality of automotive gasolines in the USA, Japan, and EU countries. In Russia and CIS countries, the requirements for the composition of automotive gasolines Catalyst Indexes

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