Self-Tandem Electrocatalytic NO Reduction to NH₃ on a W Single-Atom Catalyst

Abstract

We design single-atom W confined in MoO 3−x amorphous nanosheets (W 1 /MoO 3−x ) comprising W 1 −O 5 motifs as a highly active and durable NORR catalyst. Theoretical and operando spectroscopic investigations reveal the dual functions of W 1 −O 5 motifs to (1) facilitate the activation and protonation of NO molecules and (2) promote H 2 O dissociation while suppressing *H dimerization to increase the proton supply, eventually resulting in a self-tandem NORR mechanism of W 1 / MoO 3−x to greatly accelerate the protonation energetics of the NOto-NH 3 pathway. As a result, W 1 /MoO 3−x exhibits the highest NH 3 −Faradaic efficiency of 91.2% and NH 3 yield rate of 308.6 μmol h −1 cm −2 , surpassing that of most previously reported NORR catalysts.

Rare-earth La-doped VS2−xfor electrochemical nitrate reduction to ammonia

“…S7 †). [47][48][49][50][51] The electrochemical NO 3 RR activity of La-VS 2−x directly used as the working electrode is evaluated in an H-type cell on the basis of a standard procedure flow chart (Fig. S8 †).…”

Amorphous NiB2for electroreduction of NO to NH3

“…S3 †), indicating the metallicity of NiB 2 which favors rapid charge transport and accelerated reaction kinetics. [43][44][45][46][47][48][49] Electrochemical NORR measurements are performed in a NO-saturated 0.5 M Na 2 SO 4 using a gas-tight H-type cell. 50 The gas products are detected by gas chromatography and liquid products are detected by colorimetric methods (Fig.…”

“…S3†), indicating the metallicity of NiB 2 which favors rapid charge transport and accelerated reaction kinetics. 43–49…”

Main-group indium single-atom catalysts for electrocatalytic NO reduction to NH3

“…In 1 /a-MoO 3 was prepared by a facile supercritical CO 2 approach. [43][44][45] The characteristic transmission electron microscopy (TEM, Fig. 1a) image of In 1 /a-MoO 3 presents a nanosheet morphology, while the high-resolution TEM (HRTEM, Fig.…”