Photovoltaic Devices (Solar Cells)

Photovoltaic devices convert incident sunlight directly into electrical energy through the photovoltaic effect in semiconductor materials. At their core, these devices rely on an energy band gap to absorb photons and generate electron–hole pairs, which are then separated and driven by internal electric fields toward selective contacts. Modern photovoltaic technologies span crystalline silicon wafers, thin‐film chalcogenides and oxides (such as CdTe, CIGS and amorphous silicon) and emerging hybrid perovskites. Crystalline silicon remains dominant owing to its stability and mature manufacturing, but demands wafer thicknesses of hundreds of micrometres to achieve sufficient absorption. Thin‐film cells exploit direct bandgaps with high absorption coefficients, enabling micrometre‐scale layers deposited on glass or flexible substrates. Hybrid organic–inorganic perovskites combine high absorption, tunable bandgaps and defect tolerance in solution‐processed films, and have rapidly achieved efficiencies rivaling established technologies. Across all platforms, challenges include minimising optical losses, managing carrier recombination, engineering interfaces and ensuring long‐term device stability under real‐world conditions. Continued advances in materials, device architectures and scalable processing aim to drive down costs and extend the global deployment of solar electricity.

Research from Nature Portfolio

A controllable moisture treatment of triple‐cation perovskite films has been shown to promote rapid mass transport of organic salts during crystallisation, yielding spatially homogeneous intermediates and high‐quality perovskite layers. Devices fabricated under these conditions approach 24 % power conversion efficiency (PCE) with minimal hysteresis and exhibit extended lifetimes beyond 800 h at maximum power point under continuous illumination.

Depth‐resolved wide‐angle X-ray scattering has revealed complex strain and structural heterogeneities through the thickness of mixed perovskite films. Tensile strain at the top surface correlates with accelerated moisture‐induced degradation at grain boundaries, guiding deposition protocols to achieve more uniform stress distributions and improved stability.

In thick‐film perovskite devices, where carrier‐lifetime limitations are removed, residual lattice strain has emerged as the primary performance bottleneck. Mapping of strain distributions linked to efficiency losses provides critical insights for the design of strain‐tolerant large‐area modules.

Photovoltaic Devices (Solar Cells) publication trend

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

Technical terms

Photovoltaic effect: Generation of voltage and current in a material upon absorption of photons, fundamental to solar cell operation.

Band gap: The energy difference between the valence band maximum and conduction band minimum of a semiconductor, determining the threshold photon energy for absorption.

Power conversion efficiency (PCE): The ratio of electrical power output from a solar cell to the incident solar power input, expressed as a percentage.

Fill factor (FF): The ratio of the maximum obtainable power to the product of open‐circuit voltage and short‐circuit current, indicating the quality of the device’s I–V curve.

Hysteresis: A discrepancy in solar cell performance between forward and reverse voltage scans, often linked to ion migration and interface charge trapping.

Lattice strain: Residual mechanical stress within the crystal lattice of a perovskite film, which can modulate energy levels and accelerate degradation processes.

Trap state: A localized defect level within the bandgap that can capture charge carriers, reducing mobility and increasing nonradiative recombination.

References

1. Moisture-triggered fast crystallization enables efficient and stable perovskite solar cells. Nature Communications (2022).
2. Mapping structure heterogeneities and visualizing moisture degradation of perovskite films with nano-focus WAXS. Nature Communications (2022).
3. Strain regulates the photovoltaic performance of thick-film perovskites. Nature Communications (2024).
4. Synergistic Role of Water and Oxygen Leads to Degradation in Formamidinium-Based Halide Perovskites. Journal of the American Chemical Society (2023).
5. Trace Water in Lead Iodide Affecting Perovskite Crystal Nucleation Limits the Performance of Perovskite Solar Cells. Advanced Materials (2023).
6. Zero Threshold for Water Adsorption on MAPbBr3. Small (2023).