Are substitutes to Cd-based quantum dots in displays more sustainable, effective, and cost competitive? An alternatives assessment approach

Abstract

Light emissive organics and inorganic nanoparticles are substance classes competing for applications in displays in the form of organic LEDs (OLEDs) and quantum LEDs (QLEDs), respectively. Upcoming substance classes (perovskites) and Q-OLED displays also contain novel nanomaterials and organics for these applications. However, the sustainability of these emissive substances is difficult to assess quickly and broadly because of their complexity, their inherently different structures, and their rapid evolution in the literature. We propose the use of an alternatives assessment to compare the hazard, cost, and performance of these competing substances, with a focus on replacing cadmium-containing quantum dots. The cost assessment highlights competitiveness of OLEDs because of their low amounts needed per display, but performance assessments do not identify a preferred alternative. The hazard results indicate there is no clear alternative either, with each novel nanomaterial or organic substance having different negative aspects. These results identify the need for a low-hazard high-performing alternative substance, and the assessment provides a framework for researchers to evaluate their own novel substances.