Recent Advances in TiO₂‐based Photoanodes for Photoelectrochemical Water Splitting

Abstract

Figure 8. (a) Schematic illustration for the synthesis of single-crystallite TiO 2 NR/NW arrays by use of an appropriate capping reagent. Reprinted with permission. Ref. [60] Copyright 2018, John Wiley and Sons. (b) SEM image and (c) the sizes along with the reaction time of the obtained single-crystal rutile TiO 2 NW arrays by using specific organic ligands. Reprinted with permission. Ref. [96] Copyright 2018, Royal Society of Chemistry. (d,e) SEM images and (f) XRD of the single-crystal anatase TiO 2 NR arrays obtained in a mixed chloride-sulfate solution with sulfate as capping reagent. Reprinted with permission. Ref. [98]

Construction of Photothermo-Electro Coupling Field Based on Surface Modification of Hydrogenated TiO2 Nanotube Array Photoanode and Its Improved Photoelectrochemical Water Splitting

“…21−23 Furthermore, the construction of a heterojunction between TNA and a narrow bandgap semiconductor is also an effective strategy to enhance full-spectrum light absorption and promote carrier separation at the heterointerface. 20 Recently, Cd x Zn 1−x S (CZS) solid solution has garnered significant attention due to its adjustable bandgap position, extensive visible light response, and better stability compared to CdS, making it an ideal candidate for surface modification of TiO 2 . 15,24−26 Despite these advantages, CZS/TNA as a photoanode still fails to sufficiently capture IR light and lacks surface active sites for water oxidation.…”

“…Among the various electrode materials for PEC water splitting that have been reported, TiO 2 is extensively chosen owing to its cost-effectiveness, chemical and thermal stability, nontoxicity, resistance to photocorrosion, and advantageous band edge levels that facilitate water oxidation. , Particularly, one-dimensional TiO 2 nanotube arrays (TNA) grown on Ti substrate through electrochemical anodization are the preferred choice as photoanode because of their highly organized nanostructure, controllable size, large surface area, and efficient carrier transport channels. − However, TNA also has two primary shortcomings: the wide band gap restricting effectively utilization of visible (vis)–IR light and rapid recombination of photogenerated charge carriers. ,, Among various enhanced modified strategies, such as element doping, quantum dot photosensitization, heterojunction, and cocatalyst, − the incorporation of defective Ti 3+ -induced oxygen vacancy (O V ) into the lattice of TNA by hydrogenation can effectively capture vis–IR light and facilitate the separation of photoinduced electron–hole pairs. − Furthermore, the construction of a heterojunction between TNA and a narrow bandgap semiconductor is also an effective strategy to enhance full-spectrum light absorption and promote carrier separation at the heterointerface . Recently, Cd x Zn 1– x S (CZS) solid solution has garnered significant attention due to its adjustable bandgap position, extensive visible light response, and better stability compared to CdS, making it an ideal candidate for surface modification of TiO 2 . ,− Despite these advantages, CZS/TNA as a photoanode still fails to sufficiently capture IR light and lacks surface active sites for water oxidation.…”

Two-Dimensional Sb Modified TiO2 Nanorod Arrays as Photoanodes for Efficient Solar Water Splitting

“…Therefore, various modification strategies to improve the photoresponse and charge separation rate of TiO 2 NRAs have been reported [ 21 ]. Among those strategies, the construction of heterojunctions is one of the most efficient strategies [ 22 ]. For example, Wang et al successfully fabricated g-C 3 N 4 /TiO 2 nanotube arrays (NTAs) heterojunctions and the new heterostructures of g-C 3 N 4 /TiO 2 NTAs exhibit enhanced PEC water-splitting activity.…”

Facet‐Dependent Interfacial and Photoelectrochemical Properties of TiO2 Nanoparticles

“…Titanium dioxide (TiO 2 ) possesses superior photoelectrochemical properties combined with high stability, low cost, and nontoxicity, which made it one of the most studied materials for DOI: 10.1002/admi.202300555 photo related applications. [1,2] The anatase phase attracts more interest than the rutile and brookite phases due to its better charge separation and transport properties. [3,4] For each phase, the photoelectrochemical properties are directly related to the surface structure and hence the formed TiO 2 /electrolyte interface which varies by the facet formed in the TiO 2 morphological structures.…”