The Perovskite-Info newsletter (August 10, 2021)

Researchers from Kanazawa University in Japan have found that the addition of cesium iodide can improve the stability and efficiency of certain perovskite solar cells. Added to MAPbI₃ cells by alternately depositing thin layers of MAPbI₃ and CsI, atoms from Cs migrate and become intercalated into the crystal lattice.

“Our approach allowed us to produce layers with precise control over the CsI intercalation,” said researcher Tetsuya Taima. Using this control, different Cs-inclusive perovskite crystals were created.

Researchers from China's Nanjing Tech University have developed a smart solar window technology, based on a photovoltachromic device that is able to achieve high transmittance and be self-adaptable to control indoor brightness and temperature.

The device was assembled using a full solution process in an architecture incorporating glass, a fluorine-doped tin oxide (FTO) layer, a perovskite-based PV cell, an electrochromic gel, another FTO layer, and glass.

A research team, led by Prof. Di Dawei from the Zhejiang University College of Optical Science and Engineering, recently discovered that by using germanium (Ge), an environmentally friendly group-IV element, to partially substitute lead in the perovskite, it is possible to create highly luminescent perovskite materials and devices.

Schematic of the Ge–Pb PeLED device structure. Image from Nature Communications

To resolve the toxicity problem that arises from the use of lead, an effective method has been the use of tin (Sn) as a partial or full replacement of lead in the perovskite materials. This strategy has been particularly successful for perovskite solar cells. However, tin-based (including tin-lead) perovskite materials are generally very poor light emitters, causing unsatisfactory performance of tin-based perovskite light-emitting devices (LEDs).