Enhancing quasi-2D perovskite photo voltaic cells with dicyandiamide interface engineering
by Riko Seibo
Tokyo, Japan (SPX) Sep 07, 2025
A analysis group led by Professors Pengwei Li, Yanlin Tune, and Yiqiang Zhang has launched a dicyandiamide (DCD)-based molecular bridge technique that considerably advances quasi-2D alternating-cation-interlayer (ACI) perovskite photo voltaic cells. Revealed in Nano-Micro Letters, the examine outlines a dual-function interface engineering methodology that enhances each effectivity and stability by passivating defects and regulating section distribution.
The crew reported a document energy conversion effectivity of 21.54% for DCD-treated units, in comparison with 19.05% in management samples. DCD lowered interfacial entice density by 73%, enabling quicker cost transport and decrease recombination charges. Lengthy-term testing confirmed handled units retained 94% of their preliminary effectivity after 1200 hours, outperforming untreated cells which maintained solely 84%.
The effectiveness of DCD stems from its guanidine and cyano teams. The guanidine group binds undercoordinated Pb2+ ions and fills iodide or cation vacancies, whereas the cyano group coordinates with Ti4+ in TiO2, decreasing oxygen vacancies and strengthening perovskite/ETL interfaces. DCD additionally suppressed low-n section aggregation whereas selling vertically aligned high-n phases, guaranteeing uniform cost transport.
Spectroscopic and theoretical research confirmed the mechanism. XPS and FTIR validated DCD interactions with Pb and Ti, whereas oxygen emptiness ratios dropped from 48% to 33%. Transient absorption and photoluminescence research revealed extra homogeneous section distributions, and DFT calculations highlighted sturdy CN – Ti bonding, explaining the lowered entice formation.
Efficiency testing confirmed a VOC of 1.172 V, JSC of 23.08 mA cm-2, and FF of 79.6%. Entice densities decreased greater than threefold, and recombination resistance elevated to twenty.68 kO, highlighting environment friendly cost extraction. The units maintained stability below 400 hours of steady illumination and 1200 hours of mixed thermal and environmental stress.
By integrating defect passivation with section homogenization, this strategy overcomes the standard efficiency-stability trade-off in 2D perovskite photovoltaics. The crew suggests the technique may prolong to different perovskite-based optoelectronics, together with LEDs and photodetectors, offering a common platform for scalable, high-performance machine engineering.
Analysis Report:Dicyandiamide-Driven Tailoring of the n-Value Distribution and Interface Dynamics for High-Performance ACI 2D Perovskite Solar Cells
Associated Hyperlinks
Shanghai Jiao Tong University Journal Center
All About Solar Energy at SolarDaily.com
