论文标题
莫特·索特基（Mott-Schottky
Interpretation of Mott-Schottky Plots of Photoanodes for Water Splitting
论文作者
论文摘要
大量文献报道说，需要二氧化氢和血液含量的光持有半导体，其掺杂密度在10^18-10^21 cm^-3之间。通过假设测得的电容是由光阳极内掺杂密度形成的耗竭层的电容所主导的，从莫特 - 索特基图获得了此类值。在这项工作中，我们表明在许多情况下，这种假设是错误的，因为收集触点的电子注入会产生无处不在的电容步骤，很难与耗尽层的电容相处。基于这种推理，我们得出了一个分析分辨率极限，该分析限制与假定的活性区域和光轴的表面粗糙度无关，下面无法以电容测量测量掺杂密度。我们发现，文献中报道的掺杂密度非常接近这一值，因此得出结论，没有电容测量的可靠证据证实了需要匹犬糊状物和赤铁矿光阳极含有高掺杂密度。
A large body of literature reports that both bismuth vanadate and haematite photoanodes are semiconductors with an extremely high doping density between 10^18-10^21 cm^-3. Such values are obtained from Mott-Schottky plots by assuming that the measured capacitance is dominated by the capacitance of the depletion layer formed by the doping density within the photoanode. In this work, we show that such an assumption is erroneous in many cases because the injection of electrons from the collecting contact creates a ubiquitous capacitance step that is very difficult to distinguish from that of the depletion layer. Based on this reasoning, we derive an analytical resolution limit that is independent of the assumed active area and surface roughness of the photoanode, below which doping densities cannot be measured in a capacitance measurement. We find that the reported doping densities in literature lie very close to this value and therefore conclude that there is no credible evidence from capacitance measurements that confirms that bismuth vanadate and haematite photoanodes contain high doping densities.
