Although cuprous oxide, Cu2O, has attracted attention as a promising p‐type semiconductor material for carbon dioxide reduction (CO2RR) photocatalysts, serious stability problems have always occurred ...due to photocorrosion. In this work, we fabricated hierarchical‐structured photocathodes with CuFeO2 on Cu2O nanorods by spray pyrolysis and oxygen‐controlled heat treatment to improve the stability of Cu2O from a thermodynamic perspective. Field‐emission scanning electron microscopy, field‐emission transmission electron microscopy and X‐ray diffraction confirmed that the Cu2O/CuFeO2 hierarchical nanorod structure was successfully fabricated. It was observed that the photocathodes show enhanced stability as the Fe content increases. Therefore, we report that the CuFeO2 layer enhances the stability of the Cu2O nanorod photocathode. A photocathode with a Cu : Fe atomic ratio of 1.52 : 1 has a current density of 1.1 mA/cm2 at 0.35 VRHE even after 10 linear voltage sweep repetitions, a decrease of only 8 % compared to the current density at the first sweep. Additionally, formate and acetate were produced during the CO2RR, exhibiting faradaic efficiencies (FEs) of 21.6 % and 68.6 %, respectively.
Strength through iron: Newly fabricated Cu2O/CuFeO2 hierarchical nanorods have been applied as a photocatalyst for carbon dioxide reduction. They show high stability and current density and the photocathodes show enhanced stability as the ratio of Fe increases.
The design of the material synthesis process is important because this process can be applied to a variety of materials and used in different applications. Herein, we selectively oxidized two types ...of metals in a carbon nanofiber (CNF) support and then left only one type of metal on a porous support using selective etching. Ni and MgO were formed in the CNFs through annealing, and then MgO was etched with an HCl etchant. In the selective oxidation process, two types of metal were selected by considering the oxidation tendency between the metal and C. Ni was selected as an oxidant of C, and Mg was selected as a reductant of C. The two metals with significantly different oxidation tendencies were predicted to have different reactivity with the etchant, making them suitable for selective etching. The effectiveness of selective etching was verified by energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). In EDS, the atomic concentration of Mg was selectively reduced. In TEM, the formation of a porous structure was confirmed.
Graphical Abstract
The electrochemical CO2 reduction reaction (CO2RR), which converts CO2 into value-added feedstocks and renewable fuels, has been increasingly studied as a next-generation energy and environmental ...solution. Here, we report that single-atom metal sites distributed around active materials can enhance the CO2RR performance by controlling the Lewis acidity-based local CO2 concentration. By utilizing the oxidation Gibbs free energy difference between silver (Ag), zinc (Zn), and carbon (C), we can produce Ag nanoparticle-embedded carbon nanofibers (CNFs) where Zn is atomically dispersed by a one-pot, self-forming thermal calcination process. The CO2RR performance of AgZn–CNF was investigated by a flow cell with a gas diffusion electrode (GDE). Compared to Ag–CNFs without Zn species (53% at −0.85 V vs. RHE), the faradaic efficiency (FE) of carbon monoxide (CO) was approximately 20% higher in AgZn–CNF (75% at −0.82 V vs. RHE) with 1 M KOH electrolyte.
Abstract
Although cuprous oxide, Cu
2
O, has attracted attention as a promising p‐type semiconductor material for carbon dioxide reduction (CO
2
RR) photocatalysts, serious stability problems have ...always occurred due to photocorrosion. In this work, we fabricated hierarchical‐structured photocathodes with CuFeO
2
on Cu
2
O nanorods by spray pyrolysis and oxygen‐controlled heat treatment to improve the stability of Cu
2
O from a thermodynamic perspective. Field‐emission scanning electron microscopy, field‐emission transmission electron microscopy and X‐ray diffraction confirmed that the Cu
2
O/CuFeO
2
hierarchical nanorod structure was successfully fabricated. It was observed that the photocathodes show enhanced stability as the Fe content increases. Therefore, we report that the CuFeO
2
layer enhances the stability of the Cu
2
O nanorod photocathode. A photocathode with a Cu : Fe atomic ratio of 1.52 : 1 has a current density of 1.1 mA/cm
2
at 0.35 V
RHE
even after 10 linear voltage sweep repetitions, a decrease of only 8 % compared to the current density at the first sweep. Additionally, formate and acetate were produced during the CO
2
RR, exhibiting faradaic efficiencies (FEs) of 21.6 % and 68.6 %, respectively.
The electrochemical CO
reduction reaction (CO
RR), which converts CO
into value-added feedstocks and renewable fuels, has been increasingly studied as a next-generation energy and environmental ...solution. Here, we report that single-atom metal sites distributed around active materials can enhance the CO
RR performance by controlling the Lewis acidity-based local CO
concentration. By utilizing the oxidation Gibbs free energy difference between silver (Ag), zinc (Zn), and carbon (C), we can produce Ag nanoparticle-embedded carbon nanofibers (CNFs) where Zn is atomically dispersed by a one-pot, self-forming thermal calcination process. The CO
RR performance of AgZn-CNF was investigated by a flow cell with a gas diffusion electrode (GDE). Compared to Ag-CNFs without Zn species (53% at -0.85 V
RHE), the faradaic efficiency (FE) of carbon monoxide (CO) was approximately 20% higher in AgZn-CNF (75% at -0.82 V
RHE) with 1 M KOH electrolyte.
The electrochemical CO
2
reduction reaction (CO
2
RR), which converts CO
2
into value-added feedstocks and renewable fuels, has been increasingly studied as a next-generation energy and environmental ...solution. Here, we report that single-atom metal sites distributed around active materials can enhance the CO
2
RR performance by controlling the Lewis acidity-based local CO
2
concentration. By utilizing the oxidation Gibbs free energy difference between silver (Ag), zinc (Zn), and carbon (C), we can produce Ag nanoparticle-embedded carbon nanofibers (CNFs) where Zn is atomically dispersed by a one-pot, self-forming thermal calcination process. The CO
2
RR performance of AgZn-CNF was investigated by a flow cell with a gas diffusion electrode (GDE). Compared to Ag-CNFs without Zn species (53% at −0.85 V
vs.
RHE), the faradaic efficiency (FE) of carbon monoxide (CO) was approximately 20% higher in AgZn-CNF (75% at −0.82 V
vs.
RHE) with 1 M KOH electrolyte.
Ag nanoparticles in Zn-embedded carbon nanofiber were synthesized by a simple one-pot, self-forming strategy. Charged Zn single atoms act as Lewis acidic sites and improving the CO
2
reduction reaction performance of the Ag nanoparticles.
Objective: To examine the effects of Tribulus terrestris L.(T. terrestris) extract on the modulation of calcium channels to evaluate its use in topical agents for treatment of atopic ...dermatitis.Methods: The 70% methanol extract of T. terrestris was prepared. Human HEK293 T cells with over-expressed calcium release-activated calcium channel protein 1(Orai1),transient receptor potential vanilloid 1, or transient receptor potential vanilloid 3(TRPV3)were treated with T. terrestris extract. Modulation of ion channels was measured using a conventional whole-cell patch-clamp technique.Results: T. terrestris extract(100 mg/m L) significantly inhibited Orai1 activity in Orai1-stromal interaction molecule 1 co-overexpressed HEK293 T cells. In addition, T. terrestris extract significantly increased the TRPV3 activity compared with 2-Aminoethyl diphenylborinate(100 mmol/L), which induces the full activation of TRPV3.Conclusions: Our results suggest that T. terrestris extract may have a therapeutic potential for recovery of abnormal skin barrier pathologies in atopic dermatitis through modulating the activities of calcium ion channels, Orai1 and TRPV3. This is the first study to report the modulatory effect of a medicinal plant on the function of ion channels in skin barrier.
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