Novel Green Luminescent and Phosphorescent Material: Semiconductive Nanoporous ZnMnO with Photon Confinement

Abstract

A novel green luminescent and phosphorescent material of semiconductive nanoporous ZnMnO was synthesized by the thermal nucleation of nanopores in the 20-period ZnMnO/ZnMnO multilayer structure. Nanoporous ZnMnO showed an n-type semiconducting property and exhibited an extremely strong green light emission in its luminescence and phosphorescence characteristics. This arises from the formation of the localized energy level (i.e., green emission band) within the energy band gap and the confinement of photons. The results suggest nanoporous ZnMnO to have a great potential for the new type of semiconducting green phosphors and semiconductor light-emitting diodes with lower thresholds, producing an efficient light emission. In-depth analyses on the structural, electrical, and optical properties are thoroughly examined, and the formation mechanism of nanoporous ZnMnO and the origin of the strong green light emission are discussed.

Enhanced photocatalytic crystal-violet degradation performances of sonochemically-synthesized AC-CeO2 nanocomposites

“…The smaller bandgap energy of AC-CeO 2 than CeO 2 can be ascribed to the formation of the localized band at the CeO 2 -CeO 2 interface, which might be created by anchoration of CeO 2 -CeO 2 surfaces by AC. Namely, AC provides the charge carriers at the CeO 2 surface, and the charges accumulated at the CeO 2 -CeO 2 interface could lead to band bending [73] , [74] , [75] along the aggregated CeO 2 -CeO 2 nanoparticles ( Fig. 5 (c)).…”

Upcycling of Wastewater via Effective Photocatalytic Hydrogen Production Using MnO2 Nanoparticles—Decorated Activated Carbon Nanoflakes

“…Namely, the d–d transitions of Mn ions were observed at around 500–550 nm and 620–680 nm. The former is ascribed to the intra-band transition from Mn 2+ core shells via 4 T 1 → 6 A 1 [ 59 , 60 , 61 ], and the latter is attributed to emission from the Mn dimers (i.e., Mn 2+ -Mn 2+ ) [ 62 , 63 ]. The photon energy values for those absorption bands can be confirmed to be approximately 2.34 and 1.90 eV, respectively, as represented in Figure 5 b.…”

“…Namely, the d-d transitions of Mn ions were observed at around 500-550 nm and 620-680 nm. The former is ascribed to the intra-band transition from Mn 2+ core shells via 4 T 1 → 6 A 1 [59][60][61], and the latter is attributed to emission from the Mn dimers (i.e., Mn 2+ -Mn 2+ ) [62,63].…”

Room Temperature Strong Emission and Excitonic Enhancement in Multiple‐Stacked Nano‐Porous ZnO Thin Film

“…Moreover, V O is likely localized at the edge of the porous providing the negative charge carrier to the system. As a result, the chemical potential will decrease at the porous edge, which leads to the increase of localized states and free carrier confinement . The high localized states in the annealed film produce the strong green emission.…”