Indoor Organic Photovoltaic Applications

Indoor organic photovoltaics (OPVs) harness low-intensity artificial light to power compact electronic systems, notably those underpinning the Internet of Things. By employing carbon-based semiconductors with tunable absorption spectra, these devices convert ambient light—typically from LEDs or fluorescent lamps—into electrical energy with power conversion efficiencies exceeding 25 % under ideal conditions. Key advantages include mechanical flexibility, low-temperature solution processing and spectral matching to indoor sources, which together enable conformal integration onto surfaces, textiles and curved modules. Challenges remain in optimising charge extraction at low photon flux, ensuring long-term operational stability, scaling up via roll-to-roll or blade-coating techniques and reducing non-radiative losses. Recent advances in tailored donor–acceptor chemistries, interfacial engineering and device architectures have collectively driven performance milestones, while ongoing efforts seek standardised testing protocols and robust large-area fabrication to facilitate commercial deployment of self-sustaining indoor energy harvesters.

Research from Nature Portfolio

Recent studies have demonstrated the potential of organic photovoltaic cells as laser power converters for wireless micro-power transfer. By optimising the spectral match between a 660 nm laser source and organic donor–acceptor layers, devices achieved an energy‐conversion efficiency of 36.2 % at a photon flux of 9.5 mW cm−2. These organic laser power converters sustained a continuous output of 0.5 W over a two-metre transmission distance, highlighting a viable route for off-grid charging of portable micro-electronics and expanding the utility of organic semiconductors beyond ambient lighting to targeted photonic power delivery.

Indoor Organic Photovoltaic Applications publication trend

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

Technical terms

Organic photovoltaic (OPV): A solar cell employing carbon-based semiconductors as light-absorbing and charge-transport layers.

Indoor photovoltaics (IPV): Photovoltaic devices optimised to convert low-intensity artificial light into electrical power.

Donor–acceptor blend: A mixture of electron-donor and electron-acceptor materials forming the active layer for charge separation.

Non-fullerene acceptor (NFA): A class of acceptor molecules not based on fullerene cages, offering tunable energy levels and strong light absorption.

Power conversion efficiency (PCE): The ratio of electrical power output to incident light power, expressed as a percentage.

Blade coating: A solution-based deposition technique for creating uniform thin films compatible with large-area device fabrication.

Space-charge effects: Charge accumulation within the active layer that can hinder extraction and reduce device performance at high thickness.

References

1. Precisely Controlling Polymer Acceptors with Weak Intramolecular Charge Transfer Effect and Superior Coplanarity for Efficient Indoor All‐Polymer Solar Cells with over 27% Efficiency. Advanced Materials (2024).
2. Organic laser power converter for efficient wireless micro power transfer. Nature Communications (2023).
3. High Thickness Tolerance in All‐Polymer‐Based Organic Photovoltaics Enables Efficient and Stable In‐Door Operation. Advanced Science (2024).
4. A Proposal for Typical Artificial Light Sources for the Characterization of Indoor Photovoltaic Applications. Energies (2014).
5. Indoor Organic Photovoltaics for Self‐Sustaining IoT Devices: Progress, Challenges and Practicalization. ChemSusChem (2021).
6. Scaling Considerations for Organic Photovoltaics for Indoor Applications. Solar RRL (2022).