Porous and Partially Dehydrogenated Fe²⁺‐Containing Iron Oxyhydroxide Nanosheets for Efficient Electrochemical Nitrogen Reduction Reaction (ENRR)

Abstract

The design and development of efficient catalysts for electrochemical nitrogen reduction reaction (ENRR) under ambient conditions are critical for the alternative ammonia (NH3) synthesis from N2 and H2O, wherein iron‐based electrocatalysts exhibit outstanding NH3 formation rate and Faradaic efficiency (FE). Here, the synthesis of porous and positively charged iron oxyhydroxide nanosheets by using layered ferrous hydroxide as a starting precursor, which undergoes topochemical oxidation, partial dehydrogenated reaction, and final delamination, is reported. As the electrocatalyst of ENRR, the obtained nanosheets with a monolayer thickness and 10‐nm mesopores display exceptional NH3 yield rate (28.5 µg h−1 mgcat.−1) and FE (13.2%) at a potential of −0.4 V versus RHE in a phosphate buffered saline (PBS) electrolyte. The values are much higher than those of the undelaminated bulk iron oxyhydroxide. The larger specific surface area and positive charge of the nanosheets are beneficial for providing more exposed reactive sites as well as retarding hydrogen evolution reaction. This study highlights the rational control on the electronic structure and morphology of porous iron oxyhydroxide nanosheets, expanding the scope of developing non‐precious iron‐based highly efficient ENRR electrocatalysts.

A Novel Bubble‐based Microreactor for Enhanced Mass Transfer Dynamics toward Efficient Electrocatalytic Nitrogen Reduction

“…The eNRR performance achieved in this work is comparable to many of the reported results under ambient conditions in recent years (Table S8, Supporting Information). [ 3,45–48 ] Thus, based on the above analysis, the mass transfer enhancement and HER inhibition effects could be fully demonstrated using the Ru/C and Fe/g‐CN catalytic systems as well, indicating the excellent general applicability of the BBMR.…”

Mechanistic insights into the electrolyte effects on the electrochemical nitrogen reduction reaction using copper hexacyanoferrate/f-MWCNT nano-composites

“…11 Alternatively, low-cost ENRR catalysts based on metal oxide (Fe 2 O 3 , W 18 O 49 , BiOBr, etc. ), [12][13][14] metal (oxy)hydroxide, 15,16 metal-organic-framework (MOF) and MOF-derived materials, [17][18][19][20][21] singe atoms, [22][23][24] metallenes 25 and carbon (both, doped and undoped) [26][27][28][29] have been reported; however, with poor stability and activities. 30 Therefore, there is an urgent need for the design and development of low-cost, robust ENRR catalysts.…”

Small-Sized Fen Clusters Supported on the Anatase TiO2(101) Surface as a Promising High-Performance Catalyst for the N2 Reduction Reaction

“…16−18 Due to the scarcity and high cost of noble metals, 19,20 iron (Fe) appeals to researchers in recent years owing to its low cost and promising high catalytic ability for nitrogen reduction reaction (NRR). 21 Wang et al 22 found that a single Fe atom anchored on the anatase TiO 2 (001) surfaces shows wellbalanced activity for N 2 fixation and NH 3 dissociation in NRR, based on first-principle calculations. Toprek et al 23 studied the optical properties of anatase TiO 2 (101) upon introducing one Fe atom on the surface and observed enhanced visible-light absorption.…”