论文标题
通过精确定量光子回收，揭示了钙钛矿膜的内部发光量子效率
Revealing the internal luminescence quantum efficiency of perovskite films via accurate quantification of photon recycling
论文作者
论文摘要
内部发光量子效率（$ q_ \ mathrm {i}^\ mathrm {lum} $）提供了对半导体光电质量的出色评估。确定$ q_ \ mathrm {i}^\ mathrm {lum} $ perovskite膜上的薄膜来自实验可访问的外部发光量子效率（$ q_ \ qudrm {e}^\ mathrm {lum {lum} $），这是必不可少的。 （$ p_ \ mathrm {e} $）。在这里，我们基于曲线拟合模型建立了一个分析程序，该过程准确地确定了来自光致发光（PL）光谱的p_ \ mathrm {e} $，该光谱是通过共聚焦显微镜和集成的球体设置测得的。我们表明，与早期假设相比，散射引起的最初捕获的PL解释了通常观察到的红移和扩大的PL光谱形状，并导致$ p_ \ mathrm {e} $在绝对方面高于10％以上。 Applying our model to CH$_3$NH$_3$PbI$_3$ films with exceptionally high $Q_\mathrm{e}^\mathrm{lum}$ up to 47.4% sets a real benchmark for $Q_\mathrm{i}^\mathrm{lum}$ at $78.0 \pm 0.5\%$, revealing there is比以前想象的要多于减少非辐射重组的两个范围。
The internal luminescence quantum efficiency ($Q_\mathrm{i}^\mathrm{lum}$) provides an excellent assessment of the optoelectronic quality of semiconductors. To determine $Q_\mathrm{i}^\mathrm{lum}$ of perovskite films from the experimentally accessible external luminescence quantum efficiency ($Q_\mathrm{e}^\mathrm{lum}$) it is essential to account for photon recycling, and this requires knowledge of the photon escape probability ($p_\mathrm{e}$). Here, we establish an analysis procedure based on a curve fitting model that accurately determines $p_\mathrm{e}$ of perovskite films from photoluminescence (PL) spectra measured with a confocal microscope and an integrating sphere setup. We show that scattering-induced outcoupling of initially-trapped PL explains commonly observed red-shifted and broadened PL spectral shapes and leads to $p_\mathrm{e}$ being more than 10% higher in absolute terms compared to earlier assumptions. Applying our model to CH$_3$NH$_3$PbI$_3$ films with exceptionally high $Q_\mathrm{e}^\mathrm{lum}$ up to 47.4% sets a real benchmark for $Q_\mathrm{i}^\mathrm{lum}$ at $78.0 \pm 0.5\%$, revealing there is beyond a factor of two more scope for reducing non-radiative recombination than previously thought.
