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“Pharaoh’s Snakes” Reaction-Derived Carbon with Favorable Structure and Composition as Metal-Free Oxygen Reduction Reaction Electrocatalyst

by Yuan Li, Xinyao Wang, Hong Wang, Xiaoyao Tan, Dan Liu, Jianzhou Gui, Jian Gao, Zhen Yin, Na Ma and Yun Wang

Catalysts 2023, 13(7), 1059; https://doi.org/10.3390/catal13071059 - 30 Jun 2023

Cited by 4 | Viewed by 1802

Abstract

Metal-air batteries rely on the oxygen reduction reaction (ORR) for their operation. However, the ORR is kinetically slow, necessitating the use of Pt-based catalysts, which is hindered by their high cost and limited availability. Consequently, considerable efforts have been dedicated to developing metal-free catalysts for the ORR. Among these, heteroatom-doped carbons have emerged as promising candidates by manipulating their composition and microstructure. Inspired by the ancient “Pharaoh’s snakes” reaction, this study utilized sugar, melamine, and a polymerizable ionic liquid as precursors to prepare heteroatom-doped carbons with the desired composition and structure. The resulting carbon catalyst exhibited an onset potential and half-wave potential in a 0.1 M KOH electrolyte that was comparable to those of a commercial Pt/C 20 wt.% catalyst, with values of 0.97 and 0.83 V_RHE, respectively. Furthermore, the catalyst demonstrated excellent stability, retaining 93% of its initial current after a 10,800-s test. To evaluate its practical application, the synthesized carbon was employed as the cathode catalyst in a Zn-air battery, which achieved a maximum power density of 90 mW cm⁻². This study, therefore, presents a simple yet effective method for producing metal-free heteroatom-doped carbon ORR catalysts used in various energy conversion and storage devices. Full article

(This article belongs to the Special Issue Research Advances in Electrocatalysis and Energy-Related Findings across Asia-Pacific)

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30 pages, 2374 KB

Open AccessArticle

The Journey through the Netherworld and the Death of the Sun God: A Novel Reading of Exodus 7–15 in Light of the Book of Gates

by Sanghwan Lee

Religions 2023, 14(3), 343; https://doi.org/10.3390/rel14030343 - 6 Mar 2023

Cited by 1 | Viewed by 5229

Abstract

Exodus 7:8–15:21 contains a sequence of conflicts between YHWH and Pharaoh that can be divided into three parts: the Snake Confrontation, the Ten Plagues of Egypt, and the Parting of the Reed Sea. A careful reading of the entire narrative in conjunction with a New Kingdom Egyptian funerary text—the Book of Gates (BG)—reveals that both works share a number of similarities in terms of themes, terminologies, and structure. However, significant differences also occur at some crucial junctures as the respective stories unfold. These findings suggest that the Israelite author (or group of authors) might have made use of the tradition related to BG—with polemical changes—as one of his sources in framing the Exodus 7–15 narrative, in order to juxtapose the sequence of YHWH’s miracles with the progression of Pharaoh’s impending death. In this regard, Exodus 7:8–15:21 can be read as a polemical parody of the already well-established myth concerning the sun god’s journey through the Netherworld. According to this parodic reading, YHWH is the deity par excellence who stands above the Egyptian pantheon and controls order in Egypt. Full article

(This article belongs to the Section Religions and Theologies)

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12 pages, 3341 KB

Open AccessArticle

Preparing Co/N-Doped Carbon as Electrocatalyst toward Oxygen Reduction Reaction via the Ancient “Pharaoh’s Snakes” Reaction

by Jian Gao, Mengxin Zhou, Xinyao Wang, Hong Wang, Zhen Yin, Xiaoyao Tan and Yuan Li

Batteries 2022, 8(10), 150; https://doi.org/10.3390/batteries8100150 - 1 Oct 2022

Cited by 5 | Viewed by 2494

Abstract

The oxygen reduction reaction (ORR) is of great importance for clean energy storage and conversion techniques such as fuel cells and metal–air batteries (MABs). However, the ORR is kinetically sluggish, and expensive noble metal catalysts are required. The high price and limited preservation of noble metal catalysts has largely hindered the wide application of clean power sources such as fuel cells and MABs. Therefore, it is important to prepare non-expensive metal catalysts (NPMC) to cut the price of the fuel cells and MABs for wide application. Here, we report the preparation of a Co₃O₄ carried on the N-doped carbon (Co/N-C) as the ORR NPMC with a facile Pharaoh’s Snakes reaction. The gas generated during the reaction is able to fabricate the porous structure of the resultant carbon doped with heteroatoms such as Co and N. The catalyst provides a high electrocatalytic activity towards ORR via the 4-e pathway with an onset and half-wave potential of 0.98 and 0.79 V (vs. RHE), respectively, in an electrolyte of 0.1 M KOH. The onset and half-wave potentials are close to those of the commercial Pt/C. This work demonstrates the promising potential of an ancient technology for preparing NPMCs toward the ORR. Full article

(This article belongs to the Special Issue Electrode Materials for Rechargeable Lithium Batteries)

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