Micro-mesoporous submicron silica particles with pore size tunable in a wide range: synthesis, properties and prospects for LED manufacturing

Abstract

An approach has been developed that allows the synthesis of submicron spherical silica particles with a controlled micro-mesoporous structure possessing a large specific surface area (up to 1300 m2 g−1). Particle synthesis is carried out by the hydrolysis of a mixture of various organosilanes mostly associated either with CTAB or with each other. A change in the concentration of CTAB in the reaction mixture apparently leads to a change in the formation mechanism of nuclei for the silica particle growth, which allows for varying the diameter of the synthesized particles in the range from 40–450 nm. The effect of the composition of the silica precursor ([3-(methacryloyloxy)propyl]trimethoxysilane, (3-aminopropyl)triethoxysilane and tetraethoxysilane) on the formation process and porosity of the resulting particles is studied. It was shown that by simply varying the ratio of organosilanes in the composition of the precursor, one can control the pore diameter of the particles in a wide range from 0.6–15 nm. The large-pore (up to 15 nm) silica particles are used as a matrix for the spatial distribution of luminescent carbon dots. The incorporation of carbon dots into SiO2 particles prevents their aggregation leading to emission quenching after drying, thus allowing us to obtain highly luminescent composite particles. LEDs based on the obtained composite material show bright visible luminescence with spectral characteristics similar to that of a commercial cold white LED.

Modeling of luminescence spectra in spherical microresonators with an emitting shell

“…Thus, due to the developed network of interconnected pores and their large specific surface, the mesoporous shell can be filled with more light-emitting particles and analyte, than that, which can be attached to the sphere surface. In particular, the functionalization of mesoporous materials by broadband emitters, such as organic dyes [43][44][45] and carbon nanodots [46,47], has been demonstrated.…”

Мультипористые Наночастицы Кремнезема С Углеродными Наноточками: Синтез, Оптоэлектронные И Биомедицинские Применения

“…Для изготовления белых светодиодов использовался коммерческий УФ-светодиод (LED), излучающий на длине волны 405 nm, работающий от постоянного напряжения 2.5 V. Размеры светодиода 5.0 × 2.5 mm. Люминесцентные пленки нанокомпозитов МНЧК/CD и МНЧК/CD/Ag наносились на поверхность светодиода из суспензий по методике, описанной в работе [31]. Толщина пленки составляла ∼ 10 µm.…”

Моделирование Спектров Люминесценции В Сферических Микрорезонаторах С Излучающей Оболочкой

“…Таким образом, за счет развитой сети взаимосвязанных пор и их большой удельной поверхности мезопористая оболочка может быть заполнена большим количеством светоизлучающих частиц и анализируемого вещества, чем то, которое может быть присоединено к поверхности сферы. В частности, продемонстрирована функционализация мезопористых материалов широкополосными излучателями, такими как органические красители [43][44][45] и углеродные наноточки [46,47].…”