Graphene Layer Enhances Performance of Nitride-Based Solar Cells
Researchers have demonstrated that adding a monolayer of graphene as a semitransparent contact layer improves the performance of AlInN/Si solar cells across multiple aluminum compositions. The study tested devices with aluminum content of 22%, 35%, and 43%, finding gains in short-circuit current density, fill factor, and overall power conversion efficiency without degrading open-circuit voltage. The findings suggest graphene could be a practical transparent conductive contact material for next-generation nitride-based photovoltaics.
A study submitted to arXiv examines the use of graphene as a semitransparent conductive contact in solar cells built from aluminum indium nitride (AlInN) deposited on p-type silicon (100) substrates, with a thin amorphous silicon buffer layer included to improve heterointerface quality. Three aluminum concentrations — x=0.22, 0.35, and 0.43 — were evaluated, and in each case a monolayer graphene film was transferred onto the device surface using a low-temperature process. Photovoltaic performance was measured under both illumination and dark conditions, comparing devices with and without the graphene layer. Across all compositions, graphene incorporation consistently improved short-circuit current density, fill factor, and power conversion efficiency, while open-circuit voltage remained largely unchanged. The researchers argue these results establish graphene as a viable transparent electrode option for nitride-based solar cells, a materials class of interest for wide-bandgap and multijunction photovoltaic applications. The work is a preprint and has not yet undergone formal peer review.
What's missing
As a preprint, this study has not yet been peer-reviewed. Long-term stability of the graphene contact layer under operational conditions is not addressed. The scalability and cost implications of the graphene transfer process at larger device areas are also not discussed.
What different sources said
- arXiv physicsCenter
Enhancement of nitride-based solar cells using graphene as transparent contact layer
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