Novel highly active and self-healing Co(CO3)xOHy cocatalysts on BiVO4 photoanodes for effective solar water oxidation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F20%3A73603308" target="_blank" >RIV/61989592:15310/20:73603308 - isvavai.cz</a>

Result on the web

<a href="https://pubs.rsc.org/no/content/articlehtml/2020/ta/c9ta13122a" target="_blank" >https://pubs.rsc.org/no/content/articlehtml/2020/ta/c9ta13122a</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c9ta13122a" target="_blank" >10.1039/c9ta13122a</a>

Result language

angličtina

Original language name

Novel highly active and self-healing Co(CO3)xOHy cocatalysts on BiVO4 photoanodes for effective solar water oxidation

Original language description

Recent reports show that Co-Pi cocatalysts on some photoanodes, such as Fe2O3 or BiVO4, accelerate the surface water oxidation rate, acting as a hole extracting layer that improves charge separation or as a &quot;surface passivation agent&quot;. In contrast, on semiconductors such as BiVO4, deposition of classic Co-based oxygen evolution catalysts (e.g. Co3O4, CoOOH) leads to a relatively low improvement of the photoelectrochemical (PEC) performance. This illustrates that even though a species may be an excellent electrocatalyst, it may not be an effective co-catalyst for PEC reactions. Clearly, for different semiconductors there is a need to directly identify and prepare specific, highly active and low-cost cocatalysts for promoting PEC water oxidation. Co(CO3)(0.5)(OH)center dot 0.11H(2)O (or in general Co(CO3)(x)OHy) is usually used as a precursor to synthesize a range of Co-based efficient electrocatalysts. Herein, we for the first time show that Co(CO3)(x)OHy on BiVO4 provides an excellent oxygen evolution reaction activity, even close to the so far most efficient dual-layer FeOOH/NiOOH cocatalysts. Decoration of BiVO4 with Co(CO3)(x)OHy and the resulting photoanode shows a remarkable enhancement of photocurrent, achieving a photocurrent density of 5.0 mA cm(-2) at 1.23 V-RHE with an onset potential of 0.3 V-RHE, which is one of the highest PEC activities of BiVO4 reported up to now. The outstanding PEC performance can be attributed to the improvement of charge separation and transfer efficiency caused by a uniform thin coating of Co(CO3)(x)OHy. The Co(CO3)(x)OHy exhibits the highest density of active sites, the highest surface area, and the best OER activity among the investigated cobalt-based cocatalysts. Remarkably, the Co(CO3)(x)OHy also displays a self-healing function in borate buffered electrolytes. Therefore, this work not only describes low-cost but highly active cobalt-based catalysts for PEC solar water oxidation, but additionally shows a self-repair function of this system.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Project

—

Continuities

N - Vyzkumna aktivita podporovana z neverejnych zdroju

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Materials Chemistry A

ISSN

2050-7488

e-ISSN

—

Volume of the periodical

8

Issue of the periodical within the volume

5

Country of publishing house

GB - UNITED KINGDOM

Number of pages

8

Pages from-to

2563-2570

UT code for WoS article

000521200000029

EID of the result in the Scopus database

2-s2.0-85079217586