Novel solid state emitting iridium complexes with reduced phosphorescence-self-quenching triggered by steric blocking phosphine ligands

► Ir(III) complexes equipped with steric blocking ligands are synthesized. ► Phosphorescence self-quenching mechanism is discussed. ► Steric blocking ligands can suppress phosphorescence self-quenching. ► A solid state emission with quantum yield of 0.17 is observed.