Electrochemical processes coupling carbon dioxide reduction reactions with organic oxidation reactions are promising techniques for producing clean chemicals and utilizing renewable energy. However, assessments of the economics of the coupling technology remain questionable due to diverse product combinations and significant process design variability. Here, we report a technoeconomic analysis of electrochemical carbon dioxide reduction reaction–organic oxidation reaction coproduction via conceptual process design and thereby propose potential economic combinations. We first develop a fully automated process synthesis framework to guide process simulations, which are then employed to predict the levelized costs of chemicals. We then identify the global sensitivity of current density, Faraday efficiency, and overpotential across 295 electrochemical coproduction processes to both understand and predict the levelized costs of chemicals at various technology levels. The analysis highlights the promise that coupling the carbon dioxide reduction reaction with the value-added organic oxidation reaction can secure significant economic feasibility.
Bifunctional
oxygen electrocatalysts play a vital role in important
energy conversion and storage devices. Cost-effective, abundant, and
active Co-based materials have emerged as promising bifunctional electrocatalysts
for which identifying catalytically active structures under reaction
conditions and unraveling the structure–activity relationships
are of critical importance. Here, we report the size-dependent (3–10
nm) structure and catalytic activity of bifunctional cobalt oxide
nanoparticle (CoO
x
NP) catalysts for the
oxygen evolution reaction (OER) and the oxygen reduction reaction
(ORR). In situ X-ray absorption spectroscopy (XAS) revealed that the
majority of NPs during OER and ORR were composed of the Co3O4 and CoOOH phases regardless of their particle sizes.
The OER activity increased with decreasing NP size, which correlated
to the increased oxidation state and larger surface area in smaller
NPs, whereas the ORR activity was nearly independent of NP size. These
particle size-dependent catalytic activities in conjunction with the
in situ XAS results can provide insights into the CoO
x
-catalyzed bifunctional oxygen electrode reactions.
Hollow Rh2S3 hexagonal nanoprisms, prepared by one-step formation of core–shell nanoprisms followed by the etching of a core, exhibit very high catalytic activity and excellent stability toward hydrogen evolution reaction.
Electrooxidation of glucose is investigated at nanoporous gold (NPG) with controlled surface structures by applying different deposition charges during the formation of AgÀAu layers. As the deposition charge increases, the NPG surfaces exhibit smaller ligament/pore structures and the electrocatalytic oxidation of glucose becomes more effective. Voltammetric responses of NPG suggest that the electrocatalytic oxidation arises from the enrichment of (110) or (100) surface orientation of gold with higher deposition charges. The electrooxidation of glucose is retained at NPG surfaces with higher deposition charges in the presence of Cl À , which suggests possible applications to the amperometric glucose detection in biological samples.
Nanostructured Au surfaces have unique and attractive properties as functional materials in many fields such as heterogeneous catalysis and electrocatalysis. Electrochemical deposition of Au has received much attention as a simple route for the fabrication of Au surface nanostructures. In this study, we report a simple electrodeposition of Au nanoplate structures from Au(CN)(2)(-) on Au surfaces in the absence of additives or premodification of electrode surfaces. The shape of the Au nanoplates as well as their surface structures is unique compared to other Au nanostructures electrodeposited from commonly employed AuCl(4)(-) complexes. The nanoplate Au surfaces exhibit unique electrocatalytic activities for oxygen reduction and glucose oxidation, which originate from the Au(110) and Au(100) facets present on nanoplate surfaces. A simple preparation of well-defined Au nanoplate structures would allow new opportunities in various areas utilizing Au-based substrates through further modification of Au surfaces.
The preparation of size-and shape-controlled nanoparticles has enabled the understanding of important nanoscale catalytic phenomena, resulting in the design of advanced catalysts with enhanced activities and selectivities. Metal phosphides have recently emerged as a promising class of non-precious metal catalysts for hydrogen evolution reaction (HER), which is a cornerstone in clean and environmentally benign hydrogen production. Although significant progress has been made in metal phosphide catalysts, the impact of the metal phosphide shape has not yet been explored. Herein, we investigated the shape-dependent electrocatalytic activity of nickel phosphide nanoparticles (Ni 2 P NPs) for the HER. Spherical Ni 2 P NPs mainly composed of the Ni 2 P(001) surface showed higher HER activity than rod-shaped Ni 2 P NPs with the Ni 2 P(210) surface in terms of overpotential, Tafel slope, and turnover frequency. The results imply that the Ni 2 P(001) surface would have preferential interactions with the adsorbent and a lower activation barrier for hydrogen adsorption, promoting the overall rate of HER. This study highlights the importance of morphology control in electrocatalysts to boost catalytic performances.
BackgroundAstrocytes may play important roles in the pathogenesis of Alzheimer’s disease (AD) by clearing extracellular amyloid beta (Aβ) through endocytosis and degradation. We recently showed that metallothionein 3 (Mt3), a zinc-binding metallothionein that is enriched in the central nervous system, contributes to actin polymerization in astrocytes. Because actin is likely involved in the endocytosis of Aβ, we investigated the possible role of Mt3 in Aβ endocytosis by cortical astrocytes in this study.ResultsTo assess the route of Aβ uptake, we exposed cultured astrocytes to fluorescently labeled Aβ1–40 or Aβ1–42 together with chloropromazine (CP) or methyl-beta-cyclodextrin (MβCD), inhibitors of clathrin- and caveolin-dependent endocytosis, respectively. CP treatment almost completely blocked Aβ1–40 and Aβ1–42 endocytosis, whereas exposure to MβCD had no significant effect. Actin disruption with cytochalasin D (CytD) or latrunculin B also completely blocked Aβ1–40 and Aβ1–42 endocytosis. Because the absence of Mt3 also results in actin disruption, we examined Aβ1–40 and Aβ1–42 uptake and expression in Mt3−/− astrocytes. Compared with wild-type (WT) cells, Mt3−/− cells exhibited markedly reduced Aβ1–40 and Aβ1–42 endocytosis and expression of Aβ1-42 monomers and oligomers. A similar reduction was observed in CytD-treated WT cells. Finally, actin disruption and Mt3 knockout each increased the overall levels of clathrin and the associated protein phosphatidylinositol-binding clathrin assembly protein (PICALM) in astrocytes.ConclusionsOur results suggest that the absence of Mt3 reduces Aβ uptake in astrocytes through an abnormality in actin polymerization. In light of evidence that Mt3 is downregulated in AD, our findings indicate that this mechanism may contribute to the extracellular accumulation of Aβ in this disease.
Tungsten oxide/tungsten sulfide (W18O49@WS2) core-shell nanorods prepared via a controlled sulfidization reaction of W18O49 nanowhiskers showed hydrogen evolution reaction (HER) activity superior to WS2 nanotubes, indicating the critical role of a highly conductive oxide core in enhancing HER activity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.