Chinesische Wissenschaftler entwickeln Perowskit-Silizium-Tandemsolarzelle mit einem zertifizierten Wirkungsgrad von 32,89 % und einer Leistung von 90 % nach 1.000 Betriebsstunden.

Researchers in China have developed a new „peak-selective passivation“ strategy for perovskite-silicon tandem solar cells. The breakthrough resulted in a certified efficiency of 32.89% (33.33% in the lab) and retained 90% of its initial efficiency after 1,000 hours of continuous operation. Crucially, the method is compatible with existing industrial manufacturing lines, potentially overcoming major hurdles to commercialization.

**The Context:** Perovskite-silicon tandem solar cells are widely considered the next massive leap in photovoltaics. By layering a perovskite top cell over a traditional silicon bottom cell, they can capture a broader spectrum of sunlight, pushing efficiencies far beyond the theoretical limits of silicon alone (the current world record for tandem cells is ~35%). Furthermore, they utilize cheaper, abundant materials.

**The Bottleneck:** To maximize performance, industrial silicon substrates are manufactured with tiny, pyramid-like textures designed to trap light. However, applying a perovskite layer over these uneven pyramids causes localized electrical leakage. This limits the commercial prospects of the cells and has been a massive roadblock to mass adoption.

**The Breakthrough:** The research team from the Ningbo Institute of Materials Technology and Engineering (NIMTE) solved this using polystyrene nanospheres as a template. This allowed them to precisely deposit a thin insulating layer of aluminum oxide exclusively onto the „peaks“ of the pyramids. This effectively blocks the electrical leakage pathways without sacrificing the light-trapping properties of the texture.

**Why this matters for the future:** The real significance here isn’t just the high efficiency; it’s the stability and manufacturability.

* **Stability:** Perovskites have historically been notorious for degrading rapidly under environmental stress. Retaining 90% efficiency after 1,000 hours of continuous operation is a major step toward proving they can survive real-world conditions.
* **Manufacturability:** Because this passivation strategy is relatively simple and compatible with existing industrial production lines, it drastically shortens the timeline for scaling up. No massive factory overhauls are required.

If tandem cells can be mass-produced cheaply and reliably, we could see a massive acceleration in the global transition to renewable energy, drastically lowering the levelized cost of electricity (LCOE) for solar and making it the undisputed cheapest energy source on the planet.

1000 hours…. So like a bit more than a month? Is that a benchmark?