An electroluminescent device including a first electrode, a second electrode, and a light-emitting layer disposed between the first electrode and the second electrode, the light-emitting layer including a plurality of semiconductor nanoparticles, wherein the light-emitting layer is configured to emit green light, wherein the plurality of semiconductor nanoparticles include a first semiconductor nanocrystal including indium, phosphorus, and optionally zinc, and a second semiconductor nanocrystal including a zinc chalcogenide, wherein the zinc chalcogenide includes zinc, selenium, and sulfur, wherein in the plurality of the semiconductor nanoparticles, a mole ratio of zinc to indium is greater than or equal to about 60:1, and



wherein the electroluminescent device is configured to exhibit a T90 of greater than or equal to about 120 hours as measured with an initial driving luminance of about 2700 nit.