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Ultrasonic Plasma Engineering Toward Facile Synthesis of Single-Atom M-N4/N-Doped Carbon(M=Fe,Co) as Superior Oxygen Electrocatalyst in Rechargeable Zinc-Air Batteries

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Nano-Micro Letters 2021年第4期13卷 76-95页

作者： Kai Chen Seonghee Kim minyeong je Heechae Choi Zhicong Shi Nikola Vladimir Kwang Ho Kim Oi Lun Li Department of Materials Science and Engineering Pusan National University30 Jangjeon‑dongGeumjeong‑guBusan 609‑735Republic of Korea Theoretical Materials and Chemistry Group Institute of Inorganic ChemistryUniversity of CologneGreinstr.650939 CologneGermany School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006People’s Republic of China Faculty of Mechanical Engineering and Naval Architecture University of ZagrebIvana Lucica 510002 ZagrebCroatia Global Frontier R&D Center for Hybrid Interface Materials 30 Jangjeon‑dongGeumjeong‑guBusan 46241Republic of Korea

As bifunctional oxygen evolution/reduction electrocatalysts,transition-metal-based single-atom-doped nitrogen-carbon(NC)matrices are promising successors of the corresponding noblemetal-based catalysts,offering the advantages of ultrahigh atom utilization effciency and surface active ***,the fabrication of such matrices(e.g.,well-dispersed single-atom-doped M-N4/NCs)often requires numerous steps and tedious ***,ultrasonic plasma engineering allows direct carbonization in a precursor solution containing metal phthalocyanine and *** combining with the dispersion effect of ultrasonic waves,we successfully fabricated uniform single-atom M-N4(M=Fe,Co)carbon catalysts with a production rate as high as 10 mg *** Co-N4/NC presented a bifunctional potential drop ofΔE=0.79 V,outperforming the benchmark Pt/C-Ru/C catalyst(ΔE=0.88 V)at the same catalyst *** calculations revealed that Co-N4 was the major active site with superior O2 adsorption-desorption *** a practical Zn-air battery test,the air electrode coated with Co-N4/NC exhibited a specific capacity(762.8 mAh g(-1))and power density(101.62 mW cm^(-2)),exceeding those of Pt/C-Ru/C(700.8 mAh g^(-1) and 89.16 mW cm^(-2),respectively)at the same catalyst ***,for Co-N4/NC,the potential difference increased from 1.16 to 1.47 V after 100 charge-discharge *** proposed innovative and scalable strategy was concluded to be well suited for the fabrication of single-atom-doped carbons as promising bifunctional oxygen evolution/reduction electrocatalysts for metal-air batteries.

关键词： Single-atom-doped M-N4/NC catalyst Plasma engineering ORR/OER bifunctional activity DFT calculation Rechargeable Zn-air battery

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Nanocrystalline Iron Pyrophosphate-Regulated Amorphous Phosphate Overlayer for Enhancing Solar Water Oxidation

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Nano-Micro Letters 2022年第12期14卷 387-400页

作者： Chengkai Xia Yuankai Li minyeong je Jaekyum Kim Sung Min Cho Chang Hyuck Choi Heechae Choi Tae-Hoon Kim Jung Kyu Kim School of Chemical Engineering Sungkyunkwan University(SKKU)2066 Seobu-roJangan-guSuwon 16419Republic of Korea Theoretical Materials and Chemistry Group Institute of Inorganic ChemistryUniversity of CologneGreinstr.650939 CologneGermany Department of Chemistry Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Department of Materials Science and Engineering Engineering Research CenterChonnam National UniversityGwangju 61186Republic of Korea

A rational regulation of the solar water splitting reaction pathway by adjusting the surface composition and phase structure of catalysts is a substantial approach to ameliorate the sluggish reaction kinetics and improve the energy conversion *** this study,we demonstrate a nanocrystalline iron pyrophosphate(Fe_(4)(P_(2)O_(7))_(3),FePy)-regulated hybrid overlayer with amorphous iron phosphate(FePO_(4),FePi)on the surface of metal oxide nanostructure with boosted photoelectrochemical(PEC)water *** manipulating the facile electrochemical surface treatment followed by the phosphating process,nanocrystalline FePy is localized in the FePi amorphous overlayer to form a heterogeneous hybrid *** FePy-regulated hybrid overlayer(FePy@FePi)results in significantly enhanced PEC performance with long-term *** with the homogeneous FePi amorphous overlayer,FePy@FePi can improve the charge transfer efficiency more significantly,from 60% of FePi to 79%of FePy@*** density-functional theory calculations reveal that the coexistence of FePi and FePy phases on the surface of metal oxide results in much better oxygen evolution reaction kinetics,where the FePi was found to have a typical down-hill reaction for the conversion from OH*to O_(2),while FePy has a low free energy for the formation of OH*.

关键词： Water oxidation Photoelectrochemical cell Metal pyrophosphate Electrochemical surface treatment

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A conformal titanyl phosphate amorphous overlayer for enhancing photoelectrochemical hydrogen peroxide production

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Journal of Energy Chemistry 2023年第11期86卷 399-408,I0009页

作者： Jaekyum Kim Young Eun Kim minyeong je Won Tae Hong Chang-Lyoul Lee Tae-Hoon Kim Sung Min Cho Chang Hyuck Choi Heechae Choi Woo-Seok Choe Jung Kyu Kim School of Chemical Engineering Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea SKKU Advanced Institute of Nano Technology(SAINT) Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea Theoretical Materials&Chemistry Group Institute of Inorganic ChemistryUniversity of CologneGreinstr.650939CologneGermany Advanced Photonics Research Institute(APRI) Gwangju Institute of Science and Technology(GIST)Gwangju 61005Republic of Korea Department of Materials Science and Engineering Chonnam National UniversityGwangju 61186Republic of Korea Department of Chemistry Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Institute for Convergence Research and Education in Advanced Technology(I-CREATE) Yonsei UniversitySeoul 03722Republic of Korea Department of Chemistry Xi’an Jiaotong-Liverpool UniversitySuzhou 215123JiangsuChina

Photoelectrochemical(PEC)H_(2)O_(2)production through water oxidation reaction(WOR)is a promising strategy,however,designing highly efficient and selective photoanode materials remains challenging due to competitive reaction ***,for highly enhanced PEC H_(2)O_(2)production,we present a conformal amorphous titanyl phosphate(a-TP)overlayer on nanoparticulate TiO_(2)surfaces,achieved via lysozyme-molded in-situ surface *** a-TP overlayer modulates surface adsorption energies for reaction intermediates,favoring WOR for H_(2)O_(2)production over the competing O_(2)evolution *** density functional theory calculations reveal that a-TP/TiO_(2)exhibits a substantial energy uphill for the O·*formation pathway,which disfavors O_(2)evolution but promotes H_(2)O_(2)***,the a-TP overlayer strengthens the built-in electric field,resulting in favorable ***,a-TP/TiO_(2)exhibits 3.7-fold higher Faraday efficiency(FE)of 63%at 1.76 V *** hydrogen electrode(RHE)under 1 sun illumination,compared to bare TiO_(2)(17%),representing the highest FE among TiO_(2)-based WOR H_(2)O_(2)production *** the a-TP overlayer constitutes a promising strategy for controlling reaction pathways and achieving efficient solar-to-chemical energy conversion.

关键词： Solar H_(2)O_(2) production In-situ surface reforming Titanyl phosphate Amorphous overlayer Reaction pathway control

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A sulfur self-doped multifunctional biochar catalyst for overall water splitting and a supercapacitor from Camellia japonica flowers

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Carbon Energy 2022年第4期4卷 491-505页

作者： Chengkai Xia Subramani Surendran Seulgi Ji Dohun Kim Yujin Chae Jaekyum Kim minyeong je Mi-Kyung Han Woo-Seok Choe Chang Hyuck Choi Heechae Choi Jung Kyu Kim Uk Sim School of Chemistry Engineering Sungkyunkwan UniversitySuwonRepublic of Korea Hydrogen Energy Technology Laboratory Korea Institute of Energy Technology(KENTECH)NajuRepublic of Korea Department of Materials Science&Engineering Chonnam National UniversityGwangjuRepublic of Korea Theoretical Materials&Chemistry Group University of CologneCologneGermany Research Institute NEEL SciencesInc.NajuSouth Korea Department of Chemistry Pohang University of Science and Technology(POSTECH)Gyeongsangbuk-doRepublic of Korea

A versatile use of a sulfur self-doped biochar derived from Camellia japonica(camellia)flowers is demonstrated as a multifunctional catalyst for overall water splitting and a *** native sulfur content in the camellia flower facilitates in situ self-doping of sulfur,which highly activates the camellia-driven biochar(SA-Came)as a multifunctional catalyst with the enhanced electron-transfer ability and long-term *** water splitting,an SA-Came-based electrode is highly stable and shows reaction activities in both hydrogen and oxygen evolution reactions,with overpotentials of 154 and 362 mV at 10 mA cm^(−2),*** supercapacitors,SA-Came achieves a specific capacitance of 125.42 F g^(−1)at 2 A g^(−1)and high cyclic stability in a three-electrode system in a 1 M KOH *** demonstrated a high energy density of 34.54 Wh kg^(−1)at a power density of 1600 W kg^(−1)as a symmetric hybrid supercapacitor device with a wide working potential range of 0-1.6 V.

关键词： activated carbon biomass supercapacitor sustainable chemistry water splitting

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Zn-doped nickel iron(oxy)hydroxide nanocubes passivated by polyanions with high catalytic activity and corrosion resistance for seawater oxidation

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Journal of Energy Chemistry 2023年第6期81卷 82-92,I0004页

作者： So Jung Kim Heechae Choi jeong Ho Ryu Kang Min Kim Sungwook Mhin Arpan Kumar Nayak Junghwan Bang minyeong je Ghulam Ali Kyung Yoon Chung Kyeong-Han Na Won-Youl Choi Sunghwan Yeo Jin Uk Jang HyukSu Han Department of Energy Engineering Konkuk University120 Neungdong-roGwangjin-guSeoul 05029Republic of Korea Theoretical Materials&Chemistry Group Institute of Inorganic ChemistryUniversity of CologneGreinst.650939CologneGermany Materials Lab Geobuk-ro 25-50Incheon 22793Republic of Korea Department of Materials Science and Engineering Korea National University of Transportation50 Daehak-roChungjuChungbuk 27469Republic of Korea Korea Institute of Industrial Technology 137-41 Gwahakdanji-roGangneung-siGangwon 25440Republic of Korea Department of Advanced Materials Engineering Kyonggi UniversitySuwon 16227Republic of Korea Korea Institute of Industrial Technology 156 Gaetbeol-roYeonsu-guIncheon 406-840Republic of Korea U.S.-Pakistan Center for Advanced Studies in Energy(USPCASE) National University of Sciences and Technology(NUST)H-12IslamabadPakistan Energy Storage Research Center Korea Institute of Science and TechnologyHwarang-ro 14-gil 5Seongbuk-guSeoul 02792Republic of Korea Division of Energy and Environment Technology KIST SchoolKorea University of Science and TechnologySeoul 02792Republic of Korea Department of Metal and Materials Engineering Gangneung-Wonju National University 7 JukheongilGangneungGangwon 25457Republic of Korea Smart Hydrogen Energy Center Gangneung-Wonju National University7 JukheongilGangneungGangwon 25457Republic of Korea Innovative Fuel Development Division Korea Atomic Energy Research InstituteDaedeok-daero 989-111Yuseong-guDaejeon 305-353Republic of Korea

Electrochemical water splitting to produce hydrogen fuel is a promising renewable energy-conversion ***-scale electrolysis of freshwater may deplete water resources and cause water scarcity ***,seawater electrolysis is a potential solution to the future energy and water *** seawater electrolysis,it is critical to develop cost-effective electrocatalysts to split seawater without chloride ***,we present zinc-doped nickel iron(oxy)hydroxide nanocubes passivated by negatively charged polyanions(NFZ-PBA-S)that exhibits outstanding catalytic activity,stability,and selectivity for seawater *** dopants and polyanion-rich passivated surface layers in NFZ-PBA-S could effectively repel chlorine ions and enhance corrosion resistance,enabling its excellent catalytic activity and stability for seawater oxidation.

关键词： Seawater splitting Oxygen evolution reaction Electrocatalyst Layered double hydroxide Sulfidation

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Valorization of Tree Bark-Derived Suberin in Applications for the Bio-Based Composites Industry–A Recent Review

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Journal of Renewable Materials 2024年第6期12卷 1029-1042页

作者： Aleksandra jeżo Institute of Wood Sciences and Furniture SGGWNowoursynowska St.159Warsaw02-776Poland

Bark extracts are sustainable sources of biopolymers and hold great promise for replacing fossil fuel-based polymers,for example,in wood-based *** addition to primary and secondary metabolites,tree bark also contains suberin,which plays a major role in protecting the tree from environmental *** is a natural aliphatic-aromatic cross-linked polyester present in the cell walls of both normal and damaged external tissues,the main component of which are long-chain aliphatic *** main role as a plant ingredient is to protect against microbiological factors and water *** of the most important suberin monomers are suberin fatty acids,known for their hydrophobic and barrier ***,due to the diverse chemical composition of suberin,it is an attractive alternative to hydrocarbon-based *** its potential is recognized,it is not widely used in biocomposites technology,including wood-based composites and the polymer *** article will discuss the current knowledge about the potential of suberin and its components in biocomposites technology,which will include surface finishes,composite adhesives and polymer blends.

关键词： Suberin suberinic acids wood composites biocomposites biopolyester

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Factor analysis of recent major heatwaves in East Asia

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Geoscience Frontiers 2024年第1期15卷 374-383页

作者： Arim Yoon jeongwon Kim Jooyeop Lee Hyun Min Sung je-Woo Hong Seung-Ki Min Junhong Lee Jinkyu Hong Ecosystem-Atmosphere Process Laboratory Department of Atmospheric SciencesYonsei UniversitySeoul 03722Republic of Korea National Institute of Meteorological Sciences Jeju 63568Republic of Korea Korea Adaptation Center for Climate Korea Environment InstituteSejong 30121Republic of Korea Division of Environmental Science and Engineering Pohang University of Science and TechnologyPohang 37673Republic of Korea Max Planck Institute for Meteorology Hamburg 20146Germany Institute for Convergence Research and Education in Advanced Technology Yonsei UniversitySeoulRepublic of Korea

Heatwaves(HWs)present a major hazard to our society and more extreme heatwaves are expected with future climatic ***,it is important to improve our understanding of the underlying processes that drive HWs,in order to boost our socioeconomic-ecological *** this study,we quantified the influences of key driving factors(large-scale atmospheric circulation,soil moisture,and sea surface temperature)and their synergies on recent heatwaves in East *** conducted a factor separation analysis for three recent HW events by constraining the key factors in the regional Weather Research and Forecasting model with their climatologies or pseudo-observations in different *** study showed distinct spatial variations in the HW-controlling factors in East *** synergistic interaction of large-scale circulation and soil moisture was the most important factors in the 2013 Chinese *** the 2018 HWs in Korea and Japan,the same stagnant large-scale atmospheric circulation played a dominant role in driving the HW *** land-atmosphere coupling via soil moisture,its interaction with circulation,and SST exhibited stronger influences during the Korean HW than the Japanese *** analysis also revealed temporal variations in the factors driving Korean and Chinese HWs due to typhoon passage and other multiple processes over heterogeneous surfaces(i.e.,topographically induced Foehn winds,large-scale warm advection from the warm ocean,spatial differences in soil moisture).Our findings suggest that future heatwave-related studies should consider interactive contributions of key factors,their interplay with surface heterogeneities of complex terrain.

关键词： Heatwave East Asia Large-scale circulation Soil moisture Sea surface temperature Synergistic impacts

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Fabrication and properties of lightweight zirconia with fine closed porosity

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Journal of Iron and Steel Research International 2024年第6期31卷 1449-1458页

作者： Yi-bo Zhang Hua-zhi Gu Lv-ping Fu Ao Huang Mei-je Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Lightweight refractory materials with thermal insulation properties and erosion resistance are advantageous for hightemperature *** zirconia refractories were prepared using starch as a pore-forming agent,basic magnesium carbonate as a stabilizer,and nano-zirconia as an *** effects of the nano-zirconia content on the pore and thermal insulation properties of the lightweight zirconia refractories were investigated based on the porosity,phase composition,microstructure,and thermal ***-zirconia was shown to have a high surface energy,and its addition effectively increased the driving force for sintering,reduced the sintering temperature,and promoted the sintering reaction,thereby reducing the apparent porosity and improving the density of the prepared *** to the superplasticity of nano-zirconia,the surface stress caused plastic deformation between particles,which increased the migration rate of grain boundaries and trapped more gas inside the material before it diffused to the surface,thereby enhancing the closed porosity of the *** presence of closed pores could extend the thermal conduction path,decrease the conduction rate,and hinder the conduction effect to effectively reduce the thermal conductivity of the *** a nano-zirconia content of 0.75 wt.%,the prepared lightweight zirconia had the highest closed porosity and the lowest thermal *** apparent porosity,closed porosity,and total porosity of the material were 2.8%,7.0%,and 9.8%,respectively,and the thermal conductivity at 800℃was 1.37 W m^(-1)k^(-1).

关键词： Sintering Nano-zirconia Closed pore:Thermal conductivity Refractory material

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Anode surface engineering of zinc-ion batteries using tellurium nanobelt as a protective layer for enhancing energy storage performance

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Journal of Energy Chemistry 2024年第5期92卷 113-123页

作者： Soobeom Lee Yeonjin je Boeun Seok Hyun Tae Kim Yong-Ryun Jo Soong Ju Oh Byoungyong Im Dae Guen Kim Sang-Soo Chee Geon-Hyoung An Department of Energy System Engineering Gyeongsang National UniversityJinju 52725Republic of Korea Nano Convergence Materials Center Korea Institute of Ceramic Engineering and Technology(KICET)Jinju 52851Republic of Korea Department of Materials Science and Engineering Korea UniversitySeoul 02841Republic of Korea School of Materials Science and Engineering Gyeongsang National UniversityJinju 52828Republic of Korea GIST Advanced Insitute of Instrumental Analysis(GAIA) Electron Microscopy LaboratoryGwangju Institute of Science and TechnologyGwangju 61005Republic of Korea Center for Advanced Materials and Processing Institute for Advanced EngineeringYongin 17180Republic of Korea Department of Energy Engineering Gyeongsang National UniversityJinju 52725Republic of Korea

Over the years,zinc-ion batteries(ZIBs)have attracted attention as a promising next-generation energy storage technology because of their excellent safety,long cycling performance,eco-friendliness,and high-power ***,issues,such as the corrosion and dissolution of the Zn anode,limited wet-tability,and lack of sufficient nucleation sites for Zn plating,have limited their practical *** introduction of a protective layer comprising of tellurium(Te)nanobelts onto the surface of Zn anode has emerged as a promising approach to overcome these limitations and improve the electrochemical behav-ior by enhancing the safety and wettability of ZIBs,as well as providing numerous nucleation sites for Zn *** the presence of a Te-based protective layer,the energy power density of the surface-engineered Zn anode improved significantly(ranging from 310 to 144 W h kg^(-1),over a power density range of 270 to 1,800 W kg^(-1)),and the lifespan capability was *** results demonstrate that the proposed strategy of employing Te nanobelts as a protective layer holds great promise for enhancing the energy storage performance of zIBs,making them even more attractive as a viable energy storage solution forthefuture.

关键词： Zn ion battery Anode Protective layer Tellurium Nanobelt

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Mucinous neoplasm of the appendix:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 944-954页

作者： Hao-Cheng Chang Jung-Cheng Kang Ta-Wei Pu Ruei-Yu Su Chao-Yang Chen je-Ming Hu Department of Surgery Tri-Service General HospitalTaipei 114TaiwanChina Division of Colon and Rectal Surgery Department of SurgeryTaiwanChina Adventist HospitalTaipei 105TaiwanChina Division of Colon and Rectal Surgery Department of SurgeryTri-Service General Hospital Songshan BranchNational Defense Medical CenterTaipei 105TaiwanChina Division of Colon and Rectal Surgery Department of SurgeryTri-Service General HospitalNational Defense Medical CenterTaipei 114TaiwanChina Department of Pathology Tri-Service General HospitalNational Defense Medical CenterTaipei 105TaiwanChina Department of Pathology and Laboratory Medicine Taoyuan Armed Forces General HospitalTaoyuan 325TaiwanChina

BACKGROUND Appendiceal mucinous neoplasms(AMNs),although not classified as rare,are relatively uncommon tumors most often discovered incidentally during colorectal *** identification of AMNs is difficult due to non-specific sym-ptoms,overlapping tumor markers with other conditions,and the potential for *** underscores the urgent need for precision in diagnosis to pre-vent severe *** SUMMARY This case report describes the unexpected discovery and treatment of a low-grade AMN(LAMN)in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma(AC).Preoperatively,non-specific gastroin-testinal symptoms and elevated tumor markers masked the presence of *** tumor,presumed to be an AMN peritoneal cyst intraoperatively,was con-firmed as LAMN through histopathological *** neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile:Positive for Ho-meobox protein CDX-2,Cytokeratin 20,special AT-rich sequence-binding protein 2,and Mucin 2 but negative for cytokeratin 7 and Paired box gene *** profile aids in distinguishing appendiceal and ovarian mucinous *** recovery was uncomplicated,and the patient initiated adjuvant chemotherapy for the colon *** This case highlights the diagnostic complexity of AMNs,emphasizing the need for vigilant identification to avert potential complications,such as pseudomyxoma peritonei.

关键词： Adenocarcinoma Appendiceal neoplasms Low-grade appendiceal mucinous neoplasm Peritoneal neoplasms Pseudomyxoma peritonei Case report

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