控制Nb(IV) SrNbO2N氧化演化光催化剂的缺陷,通过用二和氨混合物进行氨解
Rajesh Kandel1, Li Wang1, Mahya Salmanion1
1Department of Chemistry, University of California, Davis, California, USA.
ChemSusChem
|March 13, 2026
概括
使用稀释的氨气氛合成氧化 (SrNbO2N) 可以显著减少Nb4+缺陷. 这一改进提高了其在可见光驱动水分的性能,以生产绿色气.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 绿色化学 绿色化学
背景情况:
- 氧化 (SrNbO2N) 是一种耐腐蚀的半导体,非常适合可见光驱动的水分裂.
- 常见的合成方法产生Nb4+缺陷,导致电子孔重组和效率降低.
研究的目的:
- 为了最大限度地减少SrNbO2N合成中的Nb4+缺陷.
- 为了提高SrNbO2N的性能,用于光催化水分裂.
主要方法:
- 从金属氧化物中合成的 SrNbO2N 在混合13%:87% NH3/N2大气中.
- 使用电子磁共振 (EPR) 和光学吸收光谱学来表征缺陷.
- 通过氧化水的光电流和明显的量子效率来评估光催化活性.
主要成果:
- 在与稀释的NH3.3合成的SrNbO2N中观察到减少的Nb4+缺陷 (格子:8.95 × 10^15 cm^-3).
- 最小的缺陷与800和1020 nm的光学吸收率降低相关.
- 改进的SrNbO2N在400 nm时实现了1.07 mA cm^-2的光电流和5.1%的表面量子效率.
结论:
- 在 SrNbO2N 合成过程中稀释氨气氛有效地减少了 Nb4+ 缺陷.
- 减少缺陷提高了半导体在可见光驱动水分化的效率.
- 氨的稀释似乎对过渡金属氧化的合成总体来说是有益的.
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