Self-improvement of solar water oxidation for the continuously-irradiated hematite photoanode

Abstract

Both the bulk and surface electrical properties of the α-Fe2O3 photoanode are obviously self-improved under continuous irradiation.

Electrochemical techniques for photoelectrode characterisation

“…The use of the Mott-Schottky Equation (2), written here for an n-type material, requires three key assumptions to be valid: (i) the applied potential is dropped across the semiconductor only -this is not valid for heavily doped semiconductors, which demonstrate quasi-metallic behaviour, (ii) CSC is assumed to be the same as the interfacial capacitance -the contribution of the Helmholtz layer is neglected a priori, and (iii) the semiconductor surface is perfectly flat. When these assumptions are made erroneously, which is often, the consequences are an incorrect slope and intercept of the plot [2,16].…”

“…Impedance spectroscopy under illumination, or PEIS, has been used to estimate kinetic rates of charge recombination and transfer processes, which in turn can be used to estimate interfacial charge transfer efficiencies [7,8,15,16].…”

Photoinduced Surface Activation of Semiconductor Photocatalysts under Reaction Conditions: A Commonly Overlooked Phenomenon in Photocatalysis

“…Solar energy conversion by imitating natural photosynthesis in green plants is a great case of taking inspiration from nature, which has been recognized as one of the most intriguing approaches to solve the energy and environmental problems. − With merits of self-optimization and self-healing, biological systems integrating the cooperative charge transfer process can achieve an extremely high quantum efficiency in natural photosynthesis, which has enlightened and been adopted in the design of artificial photocatalysts. − Although photocatalysis has been widely studied for decades, the intrinsic mechanism for the photocatalytical active site and the activity-determining structural properties are still challenging and unclear because of the quite complex and prolonged reaction process, especially for the semiconductor-based photocatalysts. ,− …”

Constructing a full-space internal electric field in a hematite photoanode to facilitate photogenerated-carrier separation and transfer

“…The preparation method of the photoanode based on the three kinds of a-Fe 2 O 3 lms can be referred to a previous report. 43 In order to investigate the effects of doping concentration on the surface chemical state and energy band structure, we also synthesized low-, medium-and high-level Sn-doped a-Fe 2 O 3 lms. To exclude the inuence of the Sn dopant from the FTO substrate as much as possible, we rst conducted three growth cycles of the FeOOH lm by the same method as the uniformdoping sample.…”