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.

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To expedite the marketing of direct formic acid fuel cells, a peerless inexpensive binary FeOx/Pt nanocatalyst was proposed for formic acid electro-oxidation (FAO). The roles of both catalytic ingredients (FeOx and Pt) were inspired by testing the catalytic performance of FAO at the FeOx/Au and FeOx/GC analogies. The deposition of FeOx proceeded electrochemically with a post‐activating step that identified the catalyst’s structure and performance. With a proper adaptation for the deposition and activation processes, the FeOx/Pt nanocatalyst succeeded to mitigate the typical CO poisoning that represents the principal element deteriorating the catalytic performance of the direct formic acid fuel cells. It also provided a higher (eightfold) catalytic efficiency than the bare Pt substrates toward FAO with a much better durability. Field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) were all employed to inspect, respectively, the surface morphology, bulk composition, and crystal structure of the catalyst. The electrochemical impedance spectra could correlate the charge transfer resistances for FAO over the inspected set of catalysts to explore the role of FeOx in mediating the reaction mechanism.