Sub‐3 nm Ultrafine Cu₂O for Visible Light Driven Nitrogen Fixation

Abstract

Cu2O, a low‐cost, visible light responsive semiconductor photocatalyst represents an ideal candidate for visible light driven photocatalytic reduction of N2 to NH3 from the viewpoint of thermodynamics, but it remains unexplored. Reported here is the successful synthesis of uniformly sized and ultrafine Cu2O platelets, with a lateral size of <3 nm, by the in situ topotactic reduction of a CuII‐containing layered double hydroxide with ascorbic acid. The supported ultrafine Cu2O offered excellent performance and stability for the visible light driven photocatalytic reduction of N2 to NH3 (the Cu2O‐mass‐normalized rate as high as 4.10 mmol gCu2normalO −1 h−1 at λ>400 nm), with the origin of the high activity being long‐lived photoexcited electrons in trap states, an abundance of exposed active sites, and the underlying support structure. This work guides the future design of ultrafine catalysts for NH3 synthesis and other applications.

Light induced ammonia synthesis by crystalline polyoxometalate-based hybrid frameworks coupled with the Sv-1T MoS2 cocatalyst

“…The isotope labeling experiments were executed using the purified feeding gas as the nitrogen sources, which was confirmed via the 1 H-NMR spectrum. The triplet and doublet peaks related to 14 NH 4 + and 15 NH 4 + can be clearly emerged in the 1 H-NMR spectrum, respectively. The coupling constants are J N-H = 52 Hz and J N-H = 72 Hz, which reaffirms that the produced NH 3 indeed originates from NRR (Fig.…”

“…The rigorous protocols can ensure the nitrogen source of ammonia. 6 According to Andersen's purification method, 6 the feeding gases (high-purity Ar (99.999%), 14 N 2 (99.999%) and 15 N 2 (99 atom%)) were carefully purified to further verify the origin of the ammonia generated from NRR. The isotope labeling experiments were executed using the purified feeding gas as the nitrogen sources, which was confirmed via the 1 H-NMR spectrum.…”

“…[5][6][7][8] The photocatalytic NRR operated under ambient pressure at room temperature in water pos-sesses broad application prospects in view of its energy and environmental advantages. [9][10][11][12][13][14][15][16] A suitable NRR catalyst, the core of such a photocatalytic process, needs considerable visible-light absorption and enough active sites, whereas the state-of-the-art photocatalysts have always suffered from shortcomings, such as narrow range light absorption and high recombination of charge carriers. [17][18][19] The development of firenew highly efficient and stable photocatalysts remains important for the conversion of N 2 into ammonia under mild conditions.…”

Efficient sunlight promoted nitrogen fixation from air under room temperature and ambient pressure via Ti/Mo composites

“…Though 78% nitrogen in air is a handy source of raw material for ammonia industry, the big challenge is to activate nitrogen from its stable N≡N triple bonds (941 kJ/mol). [4,5] At present, the large-scale industrial nitrogen fixation is usually implemented via Haber-Bosch process to use nitrogen and hydrogen to synthesize ammonia under iron-based catalysts at high temperature and high pressure. [6] This process requires a large amount of fossil energy and emits a significant amount of carbon dioxide.…”

Cube Cu 2 O modified CoAL‐LDH p‐n heterojunction for photocatalytic hydrogen evolution

“…In addition, the S‐scheme heterojunction was constructed via the CoAl‐LDH and MoS 2 to facilitate the transfer of electrons and holes 21 . The Cu 2 O as a p‐type semiconductor was focused on by scientists 22 . It has a wide application in solar cells 23 and photocatalytic hydrogen evolution 24,25 .…”