by Riko Seibo
Tokyo, Japan (SPX) Dec 18, 2025
Researchers in South Korea have demonstrated {that a} bilayer tin oxide electron transport layer can elevate the effectivity and stability of back-contact perovskite photo voltaic cells whereas addressing key interfacial loss mechanisms.
Again-contact perovskite photo voltaic cells place the perovskite absorber on the prime of the machine stack in order that incoming gentle reaches the lively layer straight, whereas electron and hole-collection contacts and cost transport supplies are situated on the rear aspect. In typical front-contact perovskite cells, gentle should cross by means of these transport and speak to layers earlier than reaching the perovskite, which ends up in optical losses and lowers the quantity of usable gentle absorbed by the machine.
Within the back-contact structure, daylight generates electrons and holes within the perovskite layer, which then journey to their respective transport layers on the rear to type photocurrent. This geometry reduces optical losses and might enhance cost assortment and energy conversion effectivity, nevertheless it additionally forces cost carriers to maneuver over longer paths, making them extra more likely to encounter interfacial defects and endure recombination that decreases effectivity and stability.
To mitigate these losses, a workforce led by Affiliate Professor Min Kim of the College of Seoul and PhD scholar Dohun Baek of Jeonbuk Nationwide College developed a bilayer tin oxide electron transport layer deposited by spin-coating. The tin oxide construction combines a nanoparticle SnO2 layer with a sol-gel SnO2 layer to enhance interfacial contact and digital properties on the perovskite – ETL interface in back-contact gadgets.
The work, revealed on-line on July 4, 2025 and showing in Quantity 654 of the Journal of Energy Sources on October 30, 2025, explores how this bilayer modifies interface high quality and cost extraction. The researchers report that this technique targets recombination at interfaces and band alignment points which have restricted back-contact perovskite machine efficiency.
“We chosen SnO2 for the ETL as a result of its favorable conduction band alignment with perovskite and superior electron mobility in comparison with typical titanium oxide. Because of this, our bilayer ETL enhances interfacial contact, reduces recombination losses, and optimizes power alignment for electron cost carriers,” explains Dr. Kim.
To make clear the position of electron transport layer engineering, the workforce fabricated three sorts of back-contact perovskite gadgets utilizing totally different tin oxide-based ETLs: a colloidal SnO2 composed of nanoparticles, a sol-gel SnO2, and a bilayer SnO2 combining a nanoparticle layer with a sol-gel layer. Every ETL was spin-coated onto indium tin oxide substrates and patterned by photolithography, offering a constant platform for efficiency comparability.
Experimental measurements confirmed that the machine utilizing the bilayer tin oxide ETL delivered the strongest photocurrent, with a median of 33.67 picoampere, in contrast with 26.69 picoampere for the sol-gel SnO2 machine and 14.65 picoampere for the colloidal SnO2 machine. The bilayer machine additionally reached the very best energy conversion effectivity among the many three architectures, attaining a most effectivity of 4.52 % whereas exhibiting improved operational stability as a result of stronger suppression of cost recombination.
“BC-PSC gadgets maintain nice promise for a wide range of functions, together with versatile gadgets and large-area photo voltaic modules, as a result of their excessive effectivity, enhanced stability, and scalable design. We consider our findings will assist speed up the event of sensible BC-PSC applied sciences for real-world functions whereas advancing sustainable power options,” concludes Mr. Baek.
Analysis Report:Interface engineering for efficient and stable back-contact perovskite solar cells
Associated Hyperlinks
Jeonbuk National University
All About Solar Energy at SolarDaily.com
Trending Merchandise
