Lead fixation by spider web-like porphyrin polymer for stable and clean perovskite solar cells

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2022-02, Vol.429, p.132405, Article 132405
• Main Authors: Liang, Haixia, Wang, Wei David, Mai, Sibei, Lv, Xudong, Fang, Jian, Cao, Jing
• Format: Article
• Language: English
• Subjects: Lead fixation; Perovskite solar cells; Zinc porphyrin polymer
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2021.132405

A new encapsulation strategy using the spider web-like porphyrin polymer with C=O group to fix lead within perovskite lattice is prepared, and thus realizing the fabrication of stable and clean perovskite solar cells. [Display omitted] •The spider web-like porphyrin polymer (ZnP) was in-situ obtained.•The carbonyl group of ZnP can coordinate with lead ions to fix lead within perovskite lattice.•The modified perovskite solar cells revealed enhanced performance and stability. Inhabiting the escape and migration of lead ions of perovskite films is crucial for the stable and clean perovskite solar cells (PSCs). The spider web is strong and sticky to catch the prey. Inspired by that, we employed an in-situ polymerized Zinc porphyrin (ZnP) with carbonyl group to fix lead into perovskite lattice to encapsulate the perovskite films. The carbonyl group can coordinate with lead ions in the modified perovskite films to inhibit the lead leakage when soaked into water, which could also reduce the trap density and suppressed non-radiative recombination within the modified film demonstrated by the space-charge-limited current, photoluminescence intensity and the electronic impedance spectroscopy measurements. Thus, the stabilities of the treated PSCs against heating and lighting improved obviously, and the optimal Power conversion efficiency (PCE) of PSCs also increased to 20.53% with the passivation of ZnP. This finding has provided an effective method to fix lead ions in the perovskite lattice.