A Flower‐like Bismuth Oxide as an Efficient, Durable and Selective Electrocatalyst for Artificial N₂ Fixation in Ambient Condition

Abstract

Ammonia is a basic industrial chemical, which is widely used in industry and agriculture. Traditional Haber–Bosch N2 fixation process is not environmentally friendly, which not only excessively consumes energy, but releases enormous amount of greenhouse gas. Electrochemical N2 reduction is an ideal alternative to N2 fixation, but it requires effective electrocatalyst for N2 reduction reaction (NRR). Herein, we develop a flower‐like β‐Bi2O3 catalyst for artificial N2 fixation with outstanding NRR performance and selectivity in ambient condition. This β‐Bi2O3 nanoflower shows an excellent NH3 yield of 19.92 μg h−1 mg−1cat. and Faradaic Efficiency of 4.3 % at −0.8 V in 0.1 M Na2SO4 solution, better than most reported NRR electrocatalysts. This electrocatalyst also exhibits superb electrochemical stability and durability.

In Situ Fragmented Bismuth Nanoparticles for Electrocatalytic Nitrogen Reduction

“…As shown in Figure 2b and Figure S10d (Supporting Information), the in situ synthesized Bi NPs achieve a maximum NH 3 yield of 3.25 ± 0.08 µg cm −2 h −1 at −0.7 V versus RHE and maximum faradaic efficiency (FE) of 12.11 ± 0.84% at −0.6 V versus RHE, which are comparable with previously reported bismuth catalysts (Table S1, Supporting Information). [ 25–31,51–53 ] N 2 H 4 cannot be detected in the electrolytes after 1 h electrolysis by the Watt and Chrisp method (Figures S11 and S12, Supporting Information). The electrocatalytic stability of the Bi NPs was evaluated by consecutive cycling tests at −0.7 V versus RHE without changing the electrode and Nafion membrane.…”

“Nano-garden cultivation” for electrocatalysis: controlled synthesis of Nature-inspired hierarchical nanostructures

“…17,18 Interesting nanostructures resembling natural shapes can be obtained. For instance, using solvothermal or hydrothermal strategies, ower-, [19][20][21][22][23] leaf-, 24,25 coral- [26][27][28][29][30] and seaurchin-like nanostructures have been reported recently, 31,32 demonstrating much enhanced performances in different applications. However, the biomimetic appearance of these patterns during the synthesis, in many cases, is not based on predictive mechanisms.…”

Exploration and Investigation of Periodic Elements for Electrocatalytic Nitrogen Reduction

“…Yang et al reported synthesis and NRR application of flower like structure β-Bi 2 O 3 . [249] Hydrothermal method was adopted to synthesize. It delivered NH 3 at 19.92 rate at −0.8 V in 0.1 m [250] As a result, it exhibited an efficiency as high as 10.26% at −0.5 V in 0.1 m HCl.…”