Growth of quantum-confined indium phosphide inside MCM-41

An array of analytical techniques comprising powder X-ray diffraction, solid-state NMR spectroscopy, high-resolution transmission electron microscopy, nitrogen adsorption, and UV/vis diffuse reflectance spectroscopy has been applied to study the incorporation of indium phosphide semiconductor inside MCM-41 materials by metal organic chemical vapor deposition. Line broadening in the X-ray diffraction patterns suggests the existence of both large surface deposited indium phosphide particles and nanosized indium phosphide particles deposited within the pores. High-resolution transmission electron microscopy corroborates this result: surface deposits have been imaged, and analysis of electron diffraction patterns provides evidence of the existence of nanoparticles. Nitrogen adsorption provides information on pore filling. Quantum-confinement effects, brought about by the nanoparticle size regime, are evidenced by upfield shifting of the indium phosphide resonance in the ³¹P magic-angle-spinning NMR spectra and by blue shifting of the band gap dependent transition in the UV/vis absorption spectra.