Indoor Photovoltaic Energy Harvesting Technologies

Indoor photovoltaic (PV) energy harvesting has emerged as a crucial enabler for autonomous electronics and the Internet of Things, offering a sustainable power source under low‐intensity, narrow‐spectrum lighting conditions. Unlike outdoor solar cells designed for full‐sun spectra, indoor PV devices must optimise absorber bandgaps, charge transport layers and device architectures to match fluorescent, LED or halogen emissions typically in the range of 100–1 000 lx. Key material platforms include hydrogenated amorphous silicon, organic semiconductors, dye‐sensitised configurations and metal‐halide perovskites, each selected for their spectral absorption, fabrication simplicity and compatibility with flexible substrates. Recent progress has raised power conversion efficiencies well above 30 % under common indoor illuminants by fine‐tuning absorber composition, minimising defect densities and adopting novel deposition protocols. Beyond efficiency gains, attention is turning to long‐term stability, low‐toxicity processing and cost‐effective manufacturing, with potential applications spanning batteryless sensors, medical implants, building‐integrated electronics and consumer-level smart devices. Ongoing challenges include suppressing trap‐mediated recombination, ensuring operational stability under variable light cy­cles and scaling laboratory prototypes to large‐area modules. This multidisciplinary field draws on advances in materials science, photophysics and device engineering to deliver robust, high‐performance indoor PV solutions for next-generation autonomous technologies.

Research from Nature Portfolio

Recent studies have advanced thin‐film silicon carbide and perovskite devices specifically for low-lux environments. Controlled deposition of hydrogenated amorphous silicon carbide window layers has enhanced open-circuit voltage and fill factor, yielding conversion efficiencies approaching 10 % under 500 lx illumination through optimised absorber thickness and interface engineering. Complementary investigations into planar metal-halide perovskite cells have elucidated intensity-dependent charge-transport and recombination mechanisms, revealing how multiple defect types govern monomolecular and bimolecular losses as illumination varies. Insights from space-charge-limited current analyses and modified diode models now guide strategies to mitigate trap‐mediated recombination and improve low-light performance in next-generation indoor PV devices.

Indoor Photovoltaic Energy Harvesting Technologies publication trend

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

Technical terms

Indoor photovoltaics (IPV): Solar cells optimised for low-intensity, narrow-spectrum artificial light rather than full-sun conditions.

Power conversion efficiency (PCE): Ratio of electrical output power to incident light power under specified illumination conditions.

Bandgap: Energy difference between valence and conduction bands in a semiconductor, determining the wavelengths of light that can be absorbed.

Perovskite: A class of light-absorbing materials with a characteristic crystal structure, noted for tunable bandgaps and high optoelectronic quality.

Defect passivation: Techniques to chemically or structurally neutralise electronic trap states that hinder carrier transport and recombination losses.

Anti-solvent extraction: Deposition method in which a non-solvent is applied during film crystallisation to improve absorber morphology and uniformity.

References

1. Emerging Indoor Photovoltaic Technologies for Sustainable Internet of Things. Advanced Energy Materials (2021).
2. Photovoltaics for indoor energy harvesting. Nano Energy (2024).
3. Low-Temperature Growth of Hydrogenated Amorphous Silicon Carbide Solar Cell by Inductively Coupled Plasma Deposition Toward High Conversion Efficiency in Indoor Lighting. Scientific Reports (2017).
4. Light Intensity-dependent Variation in Defect Contributions to Charge Transport and Recombination in a Planar MAPbI3 Perovskite Solar Cell. Scientific Reports (2019).
5. Large‐Area Perovskite Film Prepared by New FFASE Method for Stable Solar Modules Having High Efficiency under Both Outdoor and Indoor Light Harvesting. Advanced Science (2023).
6. Br Vacancy Defects Healed Perovskite Indoor Photovoltaic Modules with Certified Power Conversion Efficiency Exceeding 36%. Advanced Science (2022).