Semitransparent Organic Photovoltaics for Energy Applications

Semitransparent organic photovoltaics (ST-OPVs) represent a convergence of lightweight, flexible solar technology with aesthetic and architectural integration. By combining conjugated polymers or small‐molecule donors with fullerene or non-fullerene acceptors, these devices harvest near-infrared and ultraviolet light while transmitting visible wavelengths. Key performance metrics include power conversion efficiency (PCE), average visible transmittance (AVT) and light utilisation efficiency (LUE), each reflecting the trade-off between electrical output and optical clarity. Various transparent electrode strategies—such as dielectric/metal/dielectric (D/M/D) multilayers, carbon-nanotube and graphene films—have been developed to replace opaque metal contacts without compromising conductivity. Optical management through antireflective coatings, photonic structures or tuned layer thickness further enhances light coupling and colour selectivity. Applications span building-integrated photovoltaics (windows, façades and skylights), power-generating glass for vehicles and self-powered Internet of Things devices. Advances in device stability, large-area fabrication and colour neutrality underpin the global potential of ST-OPVs to combine energy generation with daylighting and design flexibility, offering a pathway to more sustainable urban environments.

Research from Nature Portfolio

Studies have optimised D/M/D transparent top contacts comprising MoO₃/Ag/MoO₃ to balance conductivity with optical transmission, achieving average visible transmittance above 90% in single-junction polymer:fullerene cells. By varying the thickness of the Ag interlayer, researchers have mapped the dependence of AVT and photogenerated current density, culminating in devices that maintain over 38% AVT with current densities exceeding 60 mA cm⁻². Separately, the replacement of costly metal electrodes with aerosol-synthesised carbon nanotube films, doped via nitric acid or molybdenum oxide, has demonstrated power conversion efficiencies up to 4.1% at visible transparencies exceeding 90%. This metal-electrode-free architecture highlights the mechanical and processing advantages of nanocarbon electrodes, alongside a retention of high transparency and competitive photovoltaic performance.

Semitransparent Organic Photovoltaics for Energy Applications publication trend

The graph below shows the total number of articles in semitransparent organic photovoltaics for energy applications across all publications each year (not limited to Nature Index journals).

Technical terms

Average Visible Transmittance (AVT): The percentage of visible light transmitted through a photovoltaic device, indicating its optical clarity.

Power Conversion Efficiency (PCE): The ratio of electrical power output to incident solar power, reflecting the device’s energy-harvesting capability.

Light Utilisation Efficiency (LUE): A combined figure of merit defined as the product of PCE and AVT, capturing the trade-off between transparency and efficiency.

Dielectric/Metal/Dielectric (D/M/D) Structure: A transparent electrode configuration using a thin metal film sandwiched between dielectric layers to optimise conductivity and transmission.

Donor–Acceptor Blend: A mixture of electron-donating and electron-accepting organic semiconductors forming the active layer in an OPV, driving exciton separation and charge transport.

References

1. Design and fabrication of a semi-transparent solar cell considering the effect of the layer thickness of MoO3/Ag/MoO3 transparent top contact on optical and electrical properties. Scientific Reports (2021).
2. Metal-electrode-free Window-like Organic Solar Cells with p-Doped Carbon Nanotube Thin-film Electrodes. Scientific Reports (2016).
3. High‐Throughput Computing Guided Low/High Index Optical Coupling Layer for Record‐Performance Semitransparent Organic Solar Cells. Advanced Energy Materials (2023).
4. Transparent, near-infrared organic photovoltaic solar cells for window and energy-scavenging applications. Applied Physics Letters (2011).
5. Solution-Processed Highly Efficient Semitransparent Organic Solar Cells with Low Donor Contents. ACS Applied Energy Materials (2021).