Mater. chem. front. Mater. chem. front. Double decker NHC-cyclometallated Pt complexes for highly-efficient vacuum-deposited green OLEDs and NIR emission Melendo Irene Weatherill Lucy A. Martín Antonio Pander Piotr Dias Fernando B. Fuertes Sara Sicilia Violeta Universidad de Zaragoza 2026 research-article