Chromaticity-Tunable All-Inorganic Color Converters Fabricated by 3D Printing for Modular Plant Growth Lighting...

Traditional 3D printing of glass and ceramics faces challenges due to the limited availability of suitable slurries. These slurries must balance high photosensitivity, low viscosity, and high solid content. Current methods struggle to meet these requirements, especially when incorporating suspended particles. This gap motivated the development of new fabrication techniques. Prior research has shown that conventional approaches limit the range of printable materials. The need for chromaticity-tunable color converters in plant growth lighting remains unmet. Existing methods lack the flexibility to produce inorganic color converters with tailored shapes. The mismatch between emission and absorption spectra in plant lighting systems persists. A solution that enables modular and tunable lighting for agriculture is still lacking.

This study aimed to develop a 3D printing method that overcomes the limitations of traditional slurry-based approaches. The goal was to fabricate chromaticity-tunable all-inorganic color converters for plant growth lighting. The researchers sought to address the material constraints in photopolymerization-induced 3D printing. They focused on creating a curable UV ink that supports high solid content and low viscosity. The study also aimed to produce phosphor-in-glass (PiG) structures with specific shapes. The researchers wanted to improve heat dissipation and spectral resemblance in plant lighting. They aimed to match the emission spectra of PiG with the absorption spectra of chlorophyll and carotenoids. The ultimate goal was to enable modular and intelligent agricultural lighting systems.

The team utilized ultraviolet-assisted direct ink writing (UV-DIW) as the 3D printing method. A curable UV ink was synthesized to overcome the material limitations of traditional slurries. The ink was optimized for high photosensitivity and low viscosity. CaAlSiN3:Eu2+/BaMgAl10O17:Eu2+ phosphors were embedded in glass to create PiG structures. The researchers used an optimized heat treatment process to prepare the color converters. Dome-type and flat-type PiG structures were fabricated in batches. The dome-type PiG-based LEDs were tested for heat dissipation and divergence angle. The emission spectra of the PiG structures were compared to the absorption spectra of plant pigments.

The UV-DIW process enabled the fabrication of chromaticity-tunable all-inorganic PiG structures. The dome-type PiG-based LEDs showed improved heat dissipation and a larger divergence angle. The emission spectra of CASN/BAM-PiG closely resembled the absorption spectra of chlorophyll and carotenoids. The researchers achieved a high degree of spectral resemblance, indicating better plant lighting performance. The selective region doping in dome-type PiG reduced reabsorption effects. The fabricated PiG structures demonstrated excellent color-tunable ability. The UV-DIW method allowed for the creation of specially shaped color converters. The results suggest the superiority of the UV-DIW process in agricultural lighting applications.

The UV-DIW process successfully overcame the material limitations of traditional 3D printing methods. The fabricated PiG structures demonstrated tunable chromaticity and improved plant lighting performance. The researchers confirmed the advantage of CASN/BAM-PiG through spectral resemblance with plant pigments. The dome-type PiG-based LEDs showed better heat dissipation and divergence characteristics. The selective doping strategy reduced reabsorption effects in the PiG structures. The study supports the use of UV-DIW for modular and intelligent agricultural lighting. The results align with the authors' claim about the superiority of the UV-DIW process. The findings suggest potential for scalable and customizable plant growth lighting systems.