The Australian National University (ANU) and partners Jinko Solar, the University of New South Wales (UNSW) and the University of Melbourne have reported progress towards cost‑effective silicon-perovskite tandem modules on passivating‑contact silicon cells, including monolithic tandem efficiencies up to 34.76% on Jinko’s TOPCon platform and 26.61% on 20 cm² devices processed with scalable blade‑coating.
This work arises from the ARENA‑funded project “Cost‑effective Si/Perovskite Tandem Modules on Passivating Contact Si Cells” (TRAC005 / PRO‑1930), launched in December 2022 and scheduled to run until April 2028, which targets commercial‑ready monolithic silicon‑perovskite tandem (SPT) technology and significant production capacity by the end of the project.”
The consortium has structured the R&D around passivating‑contact polysilicon silicon bottom cells compatible with Jinko’s production line, wide‑bandgap (~1.67 eV) inverted perovskite top cells scaled with industrially relevant solution processes, and adapted encapsulation that addresses perovskite sensitivity to moisture and oxygen, all aligned with the “30:30:30” vision (>30% module efficiency, ≈30 cents/W, ≈30‑year lifetime).
Jinko’s 34.76% record tandem result is attributed to high‑performance n‑type TOPCon base cells, defect‑passivated perovskite interfaces, improved perovskite crystallization and optimized vertical charge‑transport strategies, while the 26.61% 20 cm² devices demonstrate that industrially relevant blade coating can deliver world‑class large‑area tandem performance.
Stability testing aligned with IEC 61215 shows <10% efficiency loss after extended damp‑heat (85 °C, 85% RH), 400 thermal cycles between −40 °C and 85 °C and high‑dose UV exposure, with <10% degradation after 1,000 hours of one‑sun operation and >80% power retention from the best cells during four months of outdoor field testing.
The team highlights several key learnings: mixed 2PACz/Me‑4PACz SAMs (3:1) on ITO for uniform, deep work‑function buried interfaces in 1.67 eV inverted cells; a certified 23.42% wide‑bandgap single‑junction with 86.8% fill factor that translates to 30.97% four‑terminal tandems when semi‑transparent and coupled to TOPCon silicon; energy‑yield modelling showing slightly lower perovskite bandgaps can outperform STC‑optimized designs once spectral, irradiance and temperature variations and luminescent coupling are included; thermally evaporated Me‑4PACz on NiOₓ enabling 29.6% monolithic tandems via more uniform coverage and higher work function; Cs‑Pb‑Br intermediate‑phase engineering in two‑step solution processing that yields 21.6% wide‑bandgap single‑junctions and 29.98% monolithic tandems compatible with blade and slot‑die coating; and rubidium‑ammonia surface treatments plus MX‑SAM dual‑additive strategies on NiOₓ that reach 26.9% small‑cell efficiency and a certified stabilized 21.1% PCE in 652 cm² modules over 200 thermal cycles.
The report concludes that while these efficiency and stability milestones significantly advance commercial readiness for ANU, UNSW, Melbourne University and Jinko Solar, understanding and mitigating long‑term perovskite degradation under real‑world conditions remains a critical challenge, and that carefully designed, large, high‑quality experimental datasets for AI‑driven analysis will be central to accelerating future progress in silicon–perovskite tandem technology.
