Universal in-situ cross-linking strategy enhances stability of inverted perovskite solar cells

Gap-selective self-assembled monolayers (SAMs) are ultrathin natural movies that play a vital function in fashionable optoelectronic gadgets, significantly in perovskite and silicon-perovskite tandem photo voltaic cells. Nonetheless, their inherent instability usually compromises operational efficiency of the machine.

In a examine revealed in Nature, a staff led by Prof. Yang Chunlei and Assoc. Prof. Zhang Jie from the Shenzhen Institute of Superior Expertise of the Chinese language Academy of Sciences, and Prof. Alex Okay.-Y. Jen from Metropolis College of Hong Kong, developed a common in-situ cross-linking conformational reinforcement technique for SAM molecules, successfully addressing operational stability points brought on by buried interface degradation in high-efficiency inverted perovskite photo voltaic cells.

The researchers designed a novel azide-functionalized SAM molecule, JJ24, that includes an optimized carbon chain size. This molecule can improve the distribution uniformity of the host SAM molecule CbzNaph on clear conductive oxide (TCO) substrate, and might successfully suppress the formation of defects and voids throughout the self-assembly course of.

The azide group in JJ24 may be thermally activated to type in-situ covalent cross-linking with alkyl chains of CbzNaph molecules, making a tightly assembled co-SAM layer.

This construction improves the preferential orientation of CbzNaph and suppresses TCO substrate floor publicity brought on by molecular swing below mild and thermal stress. Thus, degradation on the perovskite buried interface is inhibited, and non-radiative recombination losses on the machine interface are considerably diminished.

Utilizing this technique, the researchers fabricated inverted perovskite photo voltaic cells which achieved an authorized energy conversion effectivity (PCE) of 26.9%. The gadgets exhibited zero effectivity degradation after 1,000 hours of steady operation below ISOS-L-2 testing requirements and retained over 98% of their preliminary PCE after 700 thermal cycles between –40°C and 85°C, exhibiting top-tier stability.

This examine offers a sensible technique to boost the operational stability of high-efficiency SAM-based gadgets on tough substrates, with vital implications to advance the commercialization of inverted perovskite photovoltaics and next-generation perovskite-based tandem photo voltaic cells.