Can the efficiencies of simplified perovskite solar cells go higher?

In recent years, metal halide perovskites have emerged as star semiconducting materials in the field of optoelectronic devices owing to their fascinating optoelectronic properties. Of particular interest are perovskite solar cells (PSCs), which have witnessed skyrocketing power conversion efficiencies (PCEs) within a short period of time, and were recently certified to reach 25.5%, which is already higher than other thin film photovoltaic technologies[1]. Nevertheless, multiple layers are still needed for state-of-theart PSCs to achieve high PCEs over 21%.

Amines modulation and passivation yields record perovskite optoelectronic devices

Perovskite-based optoelectronic devices using organic–inorganic, metal halide, hybrid thin films have revolutionized the pathway towards constructing more efficient and stable photovoltaics and light-emitting electronics [1,2]. Nevertheless, solutionprocessed polycrystalline perovskite films inevitably contain a high density of crystallographic or ionic defects.

Intermarriage between amorphous and polycrystalline materials in perovskite solar cells:positive or not?

In recent few years,the research field of perovskite solar cells(PSCs)has witnessed an unprecedentedly rapid advancement in terms of skyrocketed power conversion efficiencies(PCEs)owing to the appealing optoelectronic properties of magic metal halide perovskite(MHP)materials,such as high absorption coefficient.

Stabilizing black-phase CsPbI_(3) under over 70% humidity

Recently,all-inorganic perovskites have attracted attention due to good thermal stability[1−12].Among them,CsPbI3 has the most desirable optical bandgap(~1.7 eV)for applications in optoelectronic devices[13−16].In general,making black-phase CsPbI3 film requires a high-temperature annealing up to 320℃[17,18],which inevitably raises energy consumption.Though being made at high temperature,the resulting black-phase(αorβphase)CsPbI3 film still suffers from an un-desirable phase transition under ambient conditions[19,20].Sev-eral strategies have been developed to lower the annealing temperature(90-100℃)[20−26],it is still challenging to stabilize black-phase CsPbI3 under ambient condition with high humidity and without a tedious annealing process.Herein,we developed a simple crystal redissolution(CR)strategy to make stable black-phase CsPbI3 film in ambient air with high humidity and without post-annealing.4-N,N-dimethylamino-4ʹ-Nʹ-methyl-stilbazolium tosylate(DAST)can chemically interact with CsPbI3 to reduce the formation energy of black-phase and inhibit CsPbI3 to undergo black-to-yellow phase transition.