Integrated Concentrators for Scalable High-Power Generation from Colloidal Quantum Dot Solar Cells

Abstract

Although record efficiencies in colloidal quantum dot (CQD) solar cells continue to increase, they are still demonstrated on impractically small-area devices. Concentrators can effectively enlarge the active area, allowing scaled-up energy harvesting. Here, we present an economical and scalable method to fabricate compact concentrators made from polydimethylsiloxane using 3D-printed molds, which are directly bonded to CQD solar cells. The resulting integrated systems deliver more than a 20-fold increase in photocurrent and power, as well as significant open circuit voltage enhancements, over the original cells. We use the integrated systems to identify limiting factors in CQD solar cell operation under high irradiance. Our method could pave the way to making practical high-power solution-processed solar cells.

Impedance Spectroscopy: A Versatile Technique to Understand Solution‐Processed Optoelectronic Devices

“…In particular, these devices can be well adapted for flexible electronics. During the past years, the performance of solution‐processed devices has been greatly improved and some of them are now comparable with or exceeding the conventional thin film devices . For example, perovskite‐based solar cells have already achieved higher efficiency than that made of evaporated CuIn x Ga 1‐x Se 2 and cadmium telluride .…”

Defect Passivation of Low-Temperature Processed ZnO Electron Transport Layer with Polyethylenimine for PbS Quantum Dot Photovoltaics

“…Lead sulfide (PbS) colloidal quantum dots solar cells (CQDSCs) have recently attracted enormous attentions due to their potential for multiple exciton generation and high theoretical efficiency (42%). , In addition, the large-range size-tunable band gaps of colloidal quantum dots (CQDs) allow CQDSCs to harvest short-wave infrared light. − The reported external quantum efficiency at 1350 nm could reach 80% for single-junction PbS CQDSCs . And the good air stability and solution processability of CQDs can facilitate further fabrication in large-area devices via a continuous approach. − Considering the serious surface defect problems of PbS CQDs, researchers focused on surface modification of PbS CQDs for efficient carrier separation and transport. − Recently, a solution-phase ligand-exchange strategy, combined with advanced device engineering, has boosted the power conversion efficiency (PCE) of PbS CQDSCs to 12.01% …”

Band-like electron transport in 2D quantum dot periodic lattices: the effect of realistic size distributions

“…As improvements in their synthesis are enabling narrower size distribution, complete surface passivation and better system assembly, building better quality 2D quantum dot arrays is becoming easier 4,[16][17][18] . This opens up new possibilities in materials engineering as quantum dots are highly configurable systems 15,19,20 . In order to obtain a good performance in a solar cell, one of the main quantities that needs to be investigated is the mechanism for carrier transport, as it is essential to have suitable mobility values to allow fast carrier collection, reducing recombination processes.…”