We report the first synthesis of β-SiAlON:Eu
2+ phosphors from
single-source precursors, perhydropolysilazane (PHPS), chemically modified with Al(OCH(CH
3)
2)
3, and EuCl
2. The reactions occurring during the precursor synthesis and the subsequent thermal conversion of polymeric precursors into β-SiAlON:Eu
2+ phosphors have been studied by a complementary set of analytical techniques, including infrared spectroscopy, gas chromatography–mass spectrometry, thermogravimetry–mass spectrometry, X-ray diffraction (XRD), photoluminescence spectroscopy, and scanning electron microscopy. It has been clearly established that Al(OCH(CH
3)
2)
3 immediately reacted with PHPS to afford N–Al bonds at room temperature, whereas N–Eu bond formation was suggested to proceed above 600°C accompanied by the elimination of HCl up to 1000°C in flowing N
2. The subsequent 1800°C-heat treatment for 1 h under an N
2 gas pressure at 980 kPa allowed converting the
single-source precursors into fine-grained β-SiAlON:Eu
2+ phosphors. XRD analysis revealed that the Al/Si of .09 was the critical atomic ratio in the precursor synthesis to afford single-phase β-SiAlON (
z = .55). Moreover, Eu
2+-doping was found to efficiently reduce the carbon impurity in the host β-SiAlON. The polymer-derived β-SiAlON:Eu
2+ phosphors exhibited green emission under excitation at 460 nm and achieved the highest green emission intensity at the critical dopant Eu
2+ concentration at 1.48 at%.
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