Quantum Dots in Perovskite Solar Cells

Quantum dots are nanoscale semiconductor crystals whose size-tunable bandgaps and high defect tolerance have been harnessed to enhance the performance of metal halide perovskite solar cells. By incorporating quantum dots at key interfaces or within the perovskite matrix, researchers can modulate energy level alignment, passivate trap states and suppress phase segregation, all of which serve to reduce nonradiative recombination and improve crystallinity. Typical strategies include the deposition of colloidal quantum dots as interfacial layers between perovskite absorber and charge-transport films, blending quantum dots into precursor solutions to form hybrid photoactive layers, or using quantum dots as surface patches to heal grain-boundary defects. These approaches have led to notable gains in power conversion efficiency, long-term operational stability under humidity and heat, and the potential to surpass traditional efficiency limits through intermediate-band concepts. The global significance of this research lies in its contribution to low-cost, scalable photovoltaics that combine the high efficiencies of perovskites with the robust optoelectronic properties of quantum dots.

Research from Nature Portfolio

Recent studies have demonstrated solution-processed intermediate-band solar cells in which lead sulfide quantum dots are homogeneously dispersed within methylammonium lead bromide perovskite matrices. By achieving an undistorted lattice with high quantum-dot density, these devices exhibit two-step photon absorption via an intermediate band at room temperature, opening a pathway to exceed the Shockley–Queisser efficiency limit. The work confirms that careful control of quantum-dot size, surface chemistry and perovskite composition can enable efficient sub-band and above-bandgap photocurrent generation without introducing deleterious lattice strain.

Quantum Dots in Perovskite Solar Cells publication trend

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

Technical terms

Quantum dot: nanometre-scale semiconductor crystal with size-dependent optical and electronic properties.

Perovskite: metal halide compound with ABX₃ crystal structure used as a light-absorbing semiconductor.

Passivation: treatment to neutralise electronic defect states at material surfaces or interfaces.

Bandgap: energy difference between the valence and conduction bands of a semiconductor.

Intermediate band solar cell: photovoltaic device incorporating sub-band electronic states to enable sequential absorption of low-energy photons.

Nonradiative recombination: process in which charge carriers recombine without emitting photons, reducing device efficiency.

Phase segregation: demixing of mixed-halide perovskites into domains of different composition under illumination or heat.

Interface engineering: design and modification of junctions between layers to optimise charge transfer and stability.

References

1. Controlled growth of uniform and dense perovskite layers on SnO2 via interface passivation by PbS quantum dots. EcoMat (2024).
2. Solution-processed intermediate-band solar cells with lead sulfide quantum dots and lead halide perovskites. Nature Communications (2019).
3. Quantum Dot Passivation of Halide Perovskite Films with Reduced Defects, Suppressed Phase Segregation, and Enhanced Stability. Advanced Science (2021).
4. Enhanced efficiency and stability of triple‐cation perovskite solar cells with CsPbIxBr3 − x QDs “surface patches”. SmartMat (2022).