Nanocrystal Photovoltaic Paint Sprayed With a Handheld Airbrush

A complete photovoltaic cell was fabricated using only a handheld airbrush, dilute solutions of CdSe and CdTe nanorods, commercially available silver paint, and transparent-conducting-electrode-coated glass. Produced and stored under ambient conditions, these fully functioning solar cells are stable for months. As a heterojunction cell, the migration of carriers within the CdTe and CdSe layers is polarity-dependent, which directly contributes to the photoinduced voltaic cell response observed. The suitability of a handheld airbrush to create high-quality films by varying solution concentration, air pressure, and nanorod surface functionalization was explored. Notably, ultrasmooth surfaces comparable to spin-coated quality films can be formed from 20 to 500 nm thickness, with continuous, uninterrupted optical domains such that strong light diffraction is observed. While current estimated efficiency is low (<0.01%), this method demonstrates the potential of solar cells that can be incorporated into a variety of devices of unconventional size or design.