Water splitting with polyoxometalate-treated photoanodes: enhancing performance through sensitizer design

Fielden, John; Sumliner, Jordan M.; Han, Ning; Geletii, Yurii V.; Xiang, Xu; Musaev, Djamaladdin G.; Lian, Tianquan; Hill, Craig L.

doi:10.1039/c5sc01439e

Cited by 70 publications

(32 citation statements)

References 110 publications

(44 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although this event may be limited in EA/PS/WOC systems, either by lowering the WOC concentration or by limiting WOC/PS association, this may become a serious issue in a dye‐sensitized photoanode embedding the WOC. One relevant case is the Ru 4 POM acting as a very efficient WOC in photoactivated cycles with Ru(bpy) 3 2+ /S 2 O 8 2– , but displaying low performance in Ru polypyridine sensitized photoelectrodes , . Ru 4 POM was indeed shown to oxidatively quench the *Ru(bpy) 3 2+ when associated in ion pairs.…”

Section: Discussionmentioning

confidence: 99%

Mechanistic Insights into Light‐Activated Catalysis for Water Oxidation

et al. 2019

View full text Add to dashboard Cite

The development of catalysts for water oxidation to oxygen has been the subject of intense investigation in the last decade. In parallel to the search for high catalytic performance, many works have focused on the mechanistic analysis of the process. In this perspective, the oxidation of water through light‐assisted cycles composed of an electron acceptor (EA), a photosensitizer (PS), and a water oxidation catalyst (WOC) can provide insightful and complementary information with respect to the use of chemical oxidants or to electrochemical techniques. In this minireview, we discuss the mechanistic aspects of the EA/PS/WOC photoactivated cycles, and in particular: (i) the general elementary steps; (ii) the required features and the nature of the PS employed; (iii) the electron transfer processes and kinetics from the WOC to PS+ (hole scavenging); (iv) the detrimental quenching of the PS by the WOC and the alternative mechanistic routes; (v) the identification of WOC intermediates and, finally, (vi) the transposition of the above processes into a dye‐sensitized photoanode embedding a WOC.

show abstract

Section: Discussionmentioning

confidence: 99%

Mechanistic Insights into Light‐Activated Catalysis for Water Oxidation

et al. 2019

View full text Add to dashboard Cite

show abstract

“…al. later demonstrated with oxygen measurements on a similar triad (Fielden et al, 2015 ), however, a limitation in both cases was the stability of the dye on the surface.…”

Section: Heterogeneous Polyoxometalate Water Oxidation Catalysts (Wocmentioning

confidence: 84%

Multi-Tasking POM Systems

et al. 2018

Self Cite

View full text Add to dashboard Cite

Polyoxometalate (POM)-based materials of current interest are summarized, and specific types of POM-containing systems are described in which material facilitates multiple complex interactions or catalytic processes. We specifically highlight POM-containing multi-hydrogen-bonding polymers that form gels upon exposure to select organic liquids and simultaneously catalyze hydrolytic or oxidative decontamination, as well as water oxidation catalysts (WOCs) that can be interfaced with light-absorbing photoelectrode materials for photoelectrocatalytic water splitting.

show abstract

“…Photosensitive semiconductor materials can convert light into electrical signal, which are crucial for wide applications in many fields . In order to illustrate the photosensitive activity of HPBs, we systematically investigate the photoresponse performance of these nanocomposite film electrodes.…”

Section: Resultsmentioning

confidence: 99%

A Strategy to Obtain Long‐Term Stable Heteropoly Blues for Photosensitive Property Investigations

Chen

et al. 2018

Advanced Optical Materials

View full text Add to dashboard Cite

which should have wide spectrum absorptions, anchoring groups, and appropriate energy levels in order to absorb more sunlight and excite the ground-state electrons to the excited state, then inject into the semiconductor conduction band, while the holes remain in the dye molecule form the charge separations, which ensure the effective regenerations of the photosensitizers and the unidirectional electron injections. [2] In recent decades, great efforts have been made to develop the photosensitizers with high stability, low-cost, and high solar energy conversion in the fields of photocatalysts and solar cells. [3,4] However, developing broad-spectrum photosensitizers is still a big challenge. At present, the commonly used photosensitizers including ruthenium-pyridine, porphyrin, and pure organic dyes, have efficiently improved the power conversion efficiencies (PCEs) of the DSSCs. [5] However, their large-scale productions and applications in photovoltaic industry have been limited by their high costs and the cumbersome process in the synthesis and purification of photosensitizers. [6] Furthermore, the defects of some photosensitizers in spectral absorption also restrict the utilization of sunlight. So, it is urgent to develop the photosensitizers with environment-friendly, simple preparations, low costs, and wide spectra absorptions.Heteropoly blues (HPBs) is a reductive state of polyoxometalates (POMs representing oxidation state) with fascinating structures, abundant element compositions, reversible redox properties, and wide pH stability. [7,8] The advantages of HPBs as photosensitizer are as follows: i) their wide and strong spectral absorptions in visible and near-IR regions; ii) the anchoring groups are easily to coordinated to HPBs to firmly adsorb on the semiconductor surface; iii) their energy levels involving the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) can be adjusted by the composition, structure, and charge density to ensure the effective unidirectional electron injections and photosensitizer regenerations; [9] iv) their excellent light, thermal and electrochemical stability, their ability to accept or lose "blue" electrons without any structural transformations. As a kind of the potential photosensitizer candidates, HPBs have been increasingly recognized in terms of photocatalysis and solar cells. [10][11][12][13][14] However, the instability of HPBs in the air restricts the further research of their photosensitivity and their use as the photosensitizers in DSSCs.The photosensitizer is the soul of dye-sensitized solar cells (DSSCs), i.e., the key factor influencing the performance of DSSCs. The commonly used photo sensitizers are expensive carboxylic pyridine ruthenium-based complexes, so it is urgent to develop low-cost photosensitizers. Heteropoly blues (HPBs) could be a kind of excellent photosensitizers due to their wide spectra absorption; however, most of them are hardly stable in the air. Here, a strategy of combining the improved vacuum...

show abstract

Water splitting with polyoxometalate-treated photoanodes: enhancing performance through sensitizer design

Abstract: Improved sensitizer design dramatically enhances visible light-driven water oxidation from dye-sensitized TiO2 photoanodes treated with polyoxometalate water oxidation catalyst [{Ru4O4(OH)2(H2O)4}(γ-SiW10O36)2]10–.

Cited by 70 publications

References 110 publications

Mechanistic Insights into Light‐Activated Catalysis for Water Oxidation

Mechanistic Insights into Light‐Activated Catalysis for Water Oxidation

Multi-Tasking POM Systems

A Strategy to Obtain Long‐Term Stable Heteropoly Blues for Photosensitive Property Investigations

Contact Info

Product

Resources

About