We synthesized the nanoplates with different compositions and at different temperature conditions, following a protocol previously reported by our group. The syntheses details can be found in the experimental section. The two compositions we chose for this work were CsPbBr3 and CsPbI3 PNPls, both synthesized at 110 °C and 170 °C. For simplicity, these samples will be referred to as Br-110, Br-170, I-110, and I-170 hereafter.