Back‐Illuminated Si‐Based Photoanode with Nickel Cobalt Oxide Catalytic Protection Layer

Abstract

What is the most significant result of this study? Aco-sputtered NiCoO X film coupled to Si was used as aprotec-tive catalyst for the water oxidation reactioni n1m KOH, and it showedacathodic shift of the onset voltage (> 50 mV) that is likely caused by incorporation of Fe from the KOH electrolyte. Once the activity of the sample is stabilized, no furtherd egra-dation is observed over the following6days, indicating that the demonstrated back-illuminated photoanode configuration can be considered ap romising strategy for the bottom cell of at andem water-splitting device under alkaline conditions. What prompted you to investigate this topic/problem?

Unbiased, complete solar charging of a neutral flow battery by a single Si photocathode

“…In the current study, the redox couples ferricyanide and TEMPO-sulfate give a suitable energetic combination for this electrode at pH 7. 26,28,29 The supporting electrolyte is a neutral 1 M NH 4 Cl solution with the relatively high ionic conductivity of 95 mS cm À1 . 30 The choice of redox pairs is inspired by recently reported neutral and semi-organic RFBs.…”

“…They are necessary to protect Si from corrosion in the aqueous environment. 26,28 Upon illumination, photoseparated electron and hole pairs enter the conduction and valence bands, respectively, and move as illustrated in the band diagram. Even at high SOCs (S5 †) there is sufficient potential to drive the overall battery redox reaction.…”

Semiempirical modeling of a three sublayer photoanode for highly efficient photoelectrochemical water splitting: Parameter and electrolyte optimizations

“…Our results could be at some point comparable to those of the α-Fe 2 O 3 champion nanostructures for solar water splitting [37] However, corrosion challenges remain to be addressed in the future. The proposed photoanode model could be coupled with a Si-cell to form a highly efficient hybrid device [23,24,38]. Its optical properties could be further improved by electrochemical modification [39].…”

“…The reason for ZnO alloying is expanding the solar light harvesting towards the visible region, as in the case of ZnO-GaN [22]. According to the recently published results, the most efficient photocatalytic devices were made on Si [23,24].…”

Co3O4 Nanopetals on Si as Photoanodes for the Oxidation of Organics

“…Cobalt oxide, in particular, has been shown to be effective as a protective layer in a variety of conditions [15,16], as it is particularly stable in the strongly basic conditions employed for the electro-oxidation of water. The use of Co 3 O 4 thin films as passivating layers was also explored by Yang et al [17], who obtained a stable photocurrent as high as 17 mA/cm −2 in 1 M potassium hydroxide (KOH; pH = 13.6).…”