Optoelectronic Materials for Photovoltaic Applications

Optoelectronic materials lie at the heart of solar energy conversion, enabling the direct transformation of photons into electrical current. Key classes include hybrid and inorganic perovskites, chalcohalides, Zintl phases and oxide semiconductors. Hybrid lead‐halide perovskites have achieved power conversion efficiencies above 25 % yet face challenges of long‐term stability and toxicity. Inorganic perovskites and chalcohalides, particularly those based on bismuth and antimony, offer improved environmental profiles and defect‐tolerant electronic structures. Zintl phosphides, with covalent polyanionic frameworks, extend the range of accessible bandgaps for tandem devices. Advances in synthesis—such as low‐temperature anion exchange, scalable sputtering and solution processing—have facilitated the production of phase‐pure films and nanostructures. Fundamental studies of defect physics, phonon coupling and dimensionality effects underpin strategies to engineer optimal charge‐carrier lifetimes, suppress non-radiative recombination and tailor optical absorption. Collectively, these efforts drive towards cost-effective, stable and eco-friendly photovoltaics capable of meeting global renewable-energy targets.

Research from Nature Portfolio

Recent studies have demonstrated a low-temperature anion-exchange route to synthesise bismuth chalcohalide absorbers with tunable bandgaps. Particles of BiSI, BiSeI and mixed BiSBr₁−ₓIₓ were formed below 150 °C via conversion of oxyhalide precursors, yielding phase-pure products with continuous bandgap variation between 1.5 and 2.0 eV. Films exhibited stable n-type photocurrents and high incident photon-to-current efficiencies, highlighting this method’s potential for integrating eco-friendly, wide-bandgap materials into scalable photovoltaic devices.

Optoelectronic Materials for Photovoltaic Applications publication trend

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

Technical terms

Bandgap: The energy difference between a material’s valence and conduction bands that determines the wavelength of light absorbed.

Defect tolerance: The ability of a semiconductor to maintain high performance despite the presence of crystallographic or chemical imperfections.

Tandem photovoltaics: Solar cell architectures that stack multiple absorber layers with complementary bandgaps to harvest a broader segment of the solar spectrum.

Zintl phosphide: A class of compounds featuring covalent polyanionic frameworks and cationic counterions, offering tunable optical and electronic properties.

Anion-exchange synthesis: A method that replaces one type of anion in a precursor compound with another to produce a desired phase under mild conditions.

References

1. Low‐Temperature Synthesis of Stable CaZn2P2 Zintl Phosphide Thin Films as Candidate Top Absorbers. Advanced Energy Materials (2024).
2. Prospect for Bismuth/Antimony Chalcohalides‐Based Solar Cells. Advanced Functional Materials (2023).
3. Interplay of Static and Dynamic Disorder in the Mixed-Metal Chalcohalide Sn2SbS2I3. Journal of the American Chemical Society (2023).
4. Low-Temperature Synthesis of Bismuth Chalcohalides: Candidate Photovoltaic Materialswith Easily, Continuously Controllable Band gap. Scientific Reports (2016).