Colloidal Quantum Dot Solar Cells: Progressive Deposition Techniques and Future Prospects on Large‐Area Fabrication

Abstract

large-area fabrication without compromising the power conversion efficiency (PCE) always comes with new and unexpected challenges even for well-studied and well-optimized laboratory-scale PV technologies. For instance, non-concentrated monocrystalline silicon solar cells have reached a record 26.1% PCE, [1] but the efficiencies of most recent commercial panels are typically only up to about 22% (e.g., SunPower's Maxeon 3 panels: 22.8%, LG's Neon R: 22%, Panasonic's EverVolt: 21.7%). [2] Apart from the technical challenges, cost is the main driving factor for industry when it comes to production of modules or panels by scaling up laboratory-scale research cells. Low-cost PV technologies with performance comparable to existing industrial PV technologies may help in achieving the desired cost target, and perovskite solar cell (PSC) technology is the most suitable candidate in the current scenario. [3] The last decade saw a monumental rise in PSC technology. The perovskite absorber naturally possesses most of the desired properties for highly efficient solar cells, such as long carrier diffusion length, high carrier mobility, high light absorption coefficient, and excellent defect-tolerance. [4] Both in terms of laboratory-scale research cells and large-area panels, PSCs have seen a steep rise in PCE, reaching 25.8% for research cells, [1] and 17.9% for large-area modules with size of 802 cm 2 . [2] Further, PSC processing is relatively simple and Colloidally grown nanosized semiconductors yield extremely high-quality optoelectronic materials. Many examples have pointed to near perfect photoluminescence quantum yields, allowing for technology-leading materials such as high purity color centers in display technology. Furthermore, because of high chemical yield, and improved understanding of the surfaces, these materials, particularly colloidal quantum dots (QDs) can also be ideal candidates for other optoelectronic applications. Given the urgent necessity toward carbon neutrality, electricity from solar photovoltaics will play a large role in the power generation sector. QDs are developed and shown dramatic improvements over the past 15 years as photoactive materials in photovoltaics with various innovative deposition properties which can lead to exceptionally low-cost and high-performance devices. Once the key issues related to charge transport in optically thick arrays are addressed, QD-based photovoltaic technology can become a better candidate for practical application. In this article, the authors show how the possibilities of different deposition techniques can bring QD-based solar cells to the industrial level and discuss the challenges for perovskite QD solar cells in particular, to achieve largearea fabrication for further advancing technology to solve pivotal energy and environmental issues.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202107888.

Performance Improvement of Perovskite Solar Cells by Interactions between Nano‐Sized Quantum Dots and Perovskite

“…Thanks to the significant efforts for scaling-up techniques, feasible and promising methods have been successfully developed, such as blade coating, printing, spray coating and slot die. [43] For example, slot die-printed PSCs with an area of 17 cm 2 realized a high PCE of 20.4%, which is very impressive and confirms the prospect of slot die method for the fabrication of large area device with high performance. [102] The scaling up techniques are still in the development stage and more efforts are expect for further refinement of these methods, especially with the incorporation of QDs.…”

The Rise of Colloidal Lead Halide Perovskite Quantum Dot Solar Cells

“…With the rational design of device structure and processing techniques, the realization of PQDs involved tandem solar cells will finally come true. Alternatively, though the large-scale fabrication of PQD solar cells has not been reported, it seems very promising for the layer-by-layer solution process, which is compatible with the large-area blade-coating, slot-die, and dip-coating techniques . The thickness tolerance of a QD films is improved by a P–N homojunction structure, as we have elaborated in section .…”

Tunable Photovoltaics: Adapting Solar Cell Technologies to Versatile Applications

“…Owing to the unexpansive fabrication processes, the upscaling techniques and the gained maturity over the last decade, it is believed that colloidal QD PV technology is moving forward toward commercialization. [269,270] Broader Context of the Bandgap Tuning in Single Junction SC: From a universal perspective, Peters and Buonassisi established a correlation between lab-measured efficiencies and energy yield based on satellite data for various single junction PV technologies with different bandgaps. [271] It was found that the bandgap noticeably influenced the energy yield.…”