From Rusting to Solar Power Plants: A Successful Nano-Pattering of Stainless Steel 316L for Visible Light-Induced Photoelectrocatalytic Water Splitting

Abstract

A novel propitious nanoporous anodized stainless steel 316L (NASS316L) photoanode was developed for water splitting. The anodization could successfully produce a uniform nanoporous (∼ 90 nm in pore diameter) array (∼ 2.0 μm thick) of NASS316L with a high pore density. Several techniques, including FESEM, EDX, XRD, XPS, ICP-OES, and UV–vis-NIR spectrophotometry, were employed to characterize the catalyst and to assess and interpret its activity toward water splitting. Surprisingly, the NASS316L retained almost the same composition of the bare stainless steel 316L, which recommended a symmetric dealloying mechanism during anodization. It also possessed a narrow band gap energy (1.77 eV) and a unique photoelectrocatalytic activity (∼ 4.1 mA cm–2 at 0.65 V versus Ag/AgCl, 4-fold to that of α-Fe2O3) toward water splitting. The onset potential (−0.85 V) in the photocurrent–voltage curve of the NASS316L catalyst demonstrated a negative shift in its Fermi level when compared to α-Fe2O3. The high (23% at 0.2 V vs Ag/AgCl) incident-photon-to-current conversion efficiency and the robust durability revealed from the in situ analysis of the produced H2 gas continued recommending the peerless inexpensive and abundant NASS316L catalyst for potential visible-induced solar applications.

Modifying the 316L stainless steel surface by an electrodeposition technique: towards high-performance electrodes for alkaline water electrolysis

“…Stainless steel materials have been used in large-scale production in alkaline water electrolysis technologies as they are characterised by high corrosion resistance in this environment that attributed to the spontaneous formation of a thin, adherent, and self-healing passive film on the surface. 22–25 For instance, stainless steel 316L has been deemed as an outstanding current collector as well as electrode substrate for splitting of water in alkaline media. In addition to their use as current collectors, bipolar, or end plates, stainless steel electrodes showed a good catalytic activity for catalyzing the OER in alkaline media.…”

Corrosion Behavior of Anodic Self-Ordered Porous Oxide Layers on Stainless Steel

“…It has been reported that during passivation of stainless steel there is an enrichment of nickel in the metal matrix beneath the oxide layer, as dominantly chromium and iron are oxidized to form the passive layer. 37 On the other hand, it was reported by 12 that in the case of stainless steel anodization in organic electrolytes at high voltages, all components are uniformly dissolved. In our case, XPS depth profile did not give any indication of selective dealloying.…”

“…Another method for growing a porous oxide was presented previously, 10,11 in which a squared shaped wave potential was applied in an acidic electrolyte, leading to a dissolution/deposition process to grow a disordered porous oxide film on stainless steel AISI 304 and 316L respectively. Farrag et al 12 also obtained a porous oxide layer in a 316L substrate using an acidic, fluorine containing organic based electrolyte.…”

Green Synthesis of Self‐Supported Ni−Fe Oxyhydroxide Pagoda‐Shaped Nanocone Arrays for Electrocatalytic Oxygen Evolution Reaction

“…Nowadays, commercial SS, usually consisting of transition metal elements (eg. Fe, Ni, and Cr), has received extensive attention for the electrochemical study owing to its low-cost, good conductivity and chemical stability, [3][4][5][6][7] especially in the field of electrocatalytic OER. Lots of research results have proved that SS could be converted into cheap, efficient, and stable OER electrodes through specific surface treatments, and the main active ingredient is focused on NiÀ Fe (oxy)hydroxide, which is considered as the highly active species for OER under alkaline conditions.…”