Deep-red emitting Mg2TiO4:Mn4+ phosphor ceramics for plant lighting

Abstract

In this study, deep red emitting Mg2TiO4:Mn4+ phosphor ceramics were synthesized by the high temperature solid-state reaction method. The ceramics can be excited by the 465 nm blue light and had a narrow emission with a full width at half maximum (FWMH) value of 31 nm. The peak wavelength was located at 658 nm, which matched the most efficient wavelength for photosynthesis. The crystal field strength (Dq) and the Racah parameters (B and C) are estimated by Tanabe-Sugano diagram. The thermal conductivity of the ceramics was 7.535 W/(m·K) at room temperature, which was one order of magnitude higher than that of the traditional packaging method using silicone gel. A set of phosphor converted LEDs were fabricated by mounting the phosphor ceramics onto the 460 nm blue LED chips and the CIE coordinates can move from the blue light region to the purple light region with the thickness of the ceramic increasing. These results indicated that the Mg2TiO4:Mn4+ phosphor ceramic was suitable for plant lighting when combined with a blue LED chip.

Orange‐emitting MgO–(Sr,Ba)3SiO5:Eu composite phosphor ceramics for turn signals and warm white laser lighting

“…Till now, investigations on phosphor ceramics are mainly concentrated on yellow‐ and green‐emitting ones 5–12 . A big progress has been made in developing red‐emitting phosphor ceramics recently 13–20 . On the other hand, less attention is paid to orange‐emitting phosphor ceramics having an emission maximum of about 600 nm 21–24 .…”

“…[5][6][7][8][9][10][11][12] A big progress has been made in developing red-emitting phosphor ceramics recently. [13][14][15][16][17][18][19][20] On the other hand, less attention is paid to orange-emitting phosphor ceramics having an emission maximum of about 600 nm. [21][22][23][24] However, they play key roles in regulating the light color properties of lighting sources.…”

Fabrication and characterizations of Cr3+‐doped ZnGa2O4 transparent ceramics with persistent luminescence

“…Long afterglow ceramic products have a wider range of application scenarios because of their high strength, high‐temperature resistance, wear resistance, acid and alkali corrosion resistance, water resistance, and other characteristics. For transparent ceramics, the external excitation light can penetrate the ceramics to induce the formation of the internal carrier 20,21 . Xu et al prepared YAGG:Ce 3+ ‐Cr 3+ transparent ceramics with different thicknesses by solid‐state reaction and vacuum sintering 22 .…”

“…For transparent ceramics, the external excitation light can penetrate the ceramics to induce the formation of the internal carrier. 20,21 Xu et al prepared YAGG:Ce 3+ -Cr 3+ transparent ceramics with different thicknesses by solid-state reaction and vacuum sintering. 22 Compared with phosphors, due to the typical "volume effect" of transparent ceramics, the YAGG:Ce 3+ , Cr 3+ transparent ceramics show brighter continuous emission after the blue light excitation (460 nm) stopping.…”

Mn⁴⁺ Activated Deep Red Emitting Perovskite Type Phosphors for Horticulture Lighting

“…In-house agriculture activities have been attracted interest for more than a century [1] because of the feasibility to maintain a rather stable grow environment without the interference of environmental factors (weather). Conventional light sources such as fluorescent, high-pressure sodium (HPS), metal halide, or incandescent lamps can improve the growth of plants but they suffer from rather low energy efficiency because of unsuitable emission in the green and yellow spectral range [2,3]. Furthermore, traditional overhead HPS lighting consumes 25% more energy than red and blue LEDs for the growth of greenhouse tomato [4].…”