New cycloplatinated N-heterocyclic carbene (NHC) compounds with chelate diphosphines (P^P) as ancillary ligands: [Pt(R-C^C*)(P^P)]PF₆ (R-C = Naph, P^P = dppm 1A, dppe 2A, dppbz 3A; R = CO₂Et, P^P = dppm 1B, dppe 2B, dppbz 3B) have been prepared. Their photophysical properties have been widely studied and supported by the time-dependent- density functional theory (TD-DFT). These compounds show a great thermal stability and a very efficient blue (CO₂Et-C^C*) or cyan (Naph^C*) emission in PMMA films (5%wt), with photoluminescence quantum yield (PLQY) ranging from 53% to 95%. In the solid state, the emission of the Naph^C* derivatives become orange (1A, 2A) or white (3A, dual blue and yellow emisison) due to the operating π-π intermolecular interactions. We have investigated the potential use of these materials for solid-state lighting (SSL) applications. OLEDs with different architectures containing mixtures of 1B and 3A in different ratios as dopants were fabricated. In addition two-component white light remote-phosphors were got by stacking different combinations of 1B or 3B as the blue with [Pt(bzq)(CN)(CNXyl)] (R) (bzq = benzoquinolate, Xyl= 2,6-dimethylphenyl) as the red emitter using a 365 nm LED as pumping source. By changing the blue: red ratio, warm white-light with optimal CRI and Duv values and a great range of nominal CCT (4000 K - 2000 K) was obtained.