Self-Organized Small Molecules in Robust MOFs for High-Performance Perovskite Solar Cells with Enhanced Degradation Activation Energy

A brand new strategy to improve the volatility and disordered arrangement of small organic molecule additives within doped perovskite solar cells through the construction of metal-organic frameworks (MOFs) is proposed. The Zn-TTB, self-assembling from Zn2+ and 1-(triazol-1-ly)-4-tetrazol-5-ylmethyl)benzene (TTB), inherits and arranges triazole and tetrazole groups and forms a long-chain structure surrounding metal nodes. The perovskite precursors grow along with the skeleton of Zn-TTB and produce a macromolecular intermediate phase via the MOFs-perovskite interconnection, subsequently forming superior perovskite films with enhanced stability with respect to molecular additives, as evidenced by in situ thermogravimetry-Fourier transform infrared spectroscopy measurements. Thermal analyses suggest MOF-doping increases degradation activation energies by up to >174.01 kJ mol(-1) compared to the reference sample (162.45 kJ mol(-1)). Zn-TTB-modified devices exhibit promising efficiencies (up to 23.14%) and operational stability in unencapsulated state, even under constant solar light illumination.

Automated summary

A brand new strategy of using metal-organic frameworks (MOFs) to improve the volatility and arrangement of small organic molecule additives in perovskite solar cells is proposed. The MOFs help produce superior perovskite films with enhanced stability and efficiency.