Electrochemical deposition of self-supported bifunctional copper oxide electrocatalyst for methanol oxidation and oxygen evolution reaction

ROY ANIMESH,Harsharaj S. Jadhav,조민,서정길 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.76 No.-

Electrochemical oxidation of methanol and water splitting are deemed as effective pathways forproducing ideal clean energy with low emission of pollutant. In this report, copper oxide microstructuresare directly grown on conductive Ni foam substrate by a facile electrodeposition method followed by apost-annealing treatment. The CuO/Ni@400 electrocatalyst displays an onset potential of 0.38 V vs Ag/AgCl for methanol electro-oxidation and an overpotential of 364 mV at the current density of 10 mA cm 2for oxygen evolution reaction which is better than the previously reported Cu-based catalysts in alkalinemedium.

Electrodeposition of Polyaniline (PANI) and Silver on Carbon Cloth (CC) for Solar Steam Generation Application

Animesh Roy,Sung Jea Park 한국신재생에너지학회 2022 AFORE Vol.2022 No.9

Contrasting Genetic Structures Among Populations of Two Hexagrammid Fish Species in the Northwestern Pacific

곽우석,Roy Animesh,Nakayama Kouji 한국해양과학기술원 2021 Ocean science journal Vol.56 No.3

The genetic diversity and population structure of the fat greenling (Hexagrammos otakii) from the seven coastal locations in China, Korea, and Japan and the Okhotsk atka mackerel (Pleurogrammus azonus) from two coastal locations in Korea and Japan were investigated using the mitochondrial DNA (mtDNA) control region sequences. Sequences from 231 individuals (sequence length: 436 bp) inferred 105 haplotypes in the H. otakii, and sequences from 50 individuals (sequence length: 404 bp) inferred a single haplotype in the P. azonus. The haplotype and nucleotide diversities ranged from 0.737 to 0.981 and 0.007 to 0.010, respectively, for the H. otakii, whereas both diversity indices were zero for the P. azonus. Pairwise FST statistics for the H. otakii showed genetically structured populations for Liaoning (China), Eoeundol (Korea), and Hyogo (Japan). Mismatch distribution analysis showed that all of the H. otakii populations experienced an expansion in the Late Pleistocene period, approximately 0.096–0.193 MY before the present. Meanwhile, it was found that P. azonus needs more sensitive markers than mtDNA control region and more samples to reveal genetic diversity and population structure. As a result, the present study revealed that even fish belonging to the same family and with the same ecological characteristics may have different genetic diversity.

Genetic Diversity and Population Genetic Structure of Korean Black Scraper Thamnaconus modestus in Korea and Japan Based on the mtDNA Marker

곽우석,Roy Animesh 한국해양과학기술원 2021 Ocean science journal Vol.56 No.3

Thamnaconus modestus is a commercially important species that is widely distributed in the Northwest Pacific region. To investigate the genetic diversity, demographic history, and population structure, 84 individuals were collected from two locations in Korea (Geomundo and Jumunjin) and one location in Japan (Wakasa Bay). Analysis of the mitochondrial DNA control region sequence of 373 base pairs from the 84 individuals revealed 39 haplotypes with 50 polymorphic sites. The haplotype diversity and nucleotide diversity of different populations ranged from 0.973 (0.018) to 0.981 (0.013) and from 0.020 (0.011) to 0.021 (0.011), respectively. Phylogenetic analysis revealed three distinct clades of which two were large (clade 1 and clade 2) and one was small clade (clade 3). However, there was no significant geographical clustering of the haplotypes according to the sampling locality. Demographic analysis suggested that both clades experienced Late Pleistocene population expansion. The pairwise FST and AMOVA analysis were insignificant among the populations investigated. This indicated high gene flow among the populations of Korea and Japan. The dispersal capacity of the larvae and juveniles by ocean currents and migration of adult individuals could explain the genetic homogeneity. Insufficient time to accumulate genetic variation might be another reason for the lack of genetic structure.

Hierarchical free-standing networks of MnCo₂S₄ as efficient Electrocatalyst for oxygen evolution reaction

Jadhav, Harsharaj S.,Roy, Animesh,Thorat, Gaurav M.,Chung, Wook-Jin,Seo, Jeong Gil Elsevier 2019 Journal of industrial and engineering chemistry Vol.71 No.-

<P><B>Abstract</B></P> <P>The development of highly efficient, stable and cost-effective electrocatalyst for oxygen evolution reaction (OER) is critical. Herein, we report growth of MnCo<SUB>2</SUB>S<SUB>4</SUB> flakes on SS-mesh using two-step strategy, and used as an efficient, highly active and stable electrocatalyst for OER under alkaline condition. The free-standing electrocatalyst delivers exceptional stability of 100h and activity for OER with overpotential of 290mV at a current density of 10mAcm<SUP>−2</SUP> in 1M KOH. The enhanced electrocatalytic performance was supported experimentally by electrochemical impedance spectra and measurement of the electrochemically active surface area. The high electrochemical active surface area and electrical conductivity of MnCo<SUB>2</SUB>S<SUB>4</SUB> flakes played an essential role in their high electrocatalytic performance.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MnCo<SUB>2</SUB>S<SUB>4</SUB> have been synthesized by electrodeposition followed by sulfidation. </LI> <LI> Electrocatalyst exhibits overpotential of 290mV at a 10mA/cm<SUP>2</SUP> current density. </LI> <LI> Large ECSA with plenty active sites deliver exceptional stability of 100h. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The free-standing electrocatalyst demonstrates superior activity over that of a oxide catalyst, with the need of an overpotential of 290mV to drive a geometrical catalytic current density of 10mAcm<SUP>−2</SUP> in 1M KOH, which is superior to earlier report of MnCo<SUB>2</SUB>S<SUB>4</SUB>.</P> <P>[DISPLAY OMISSION]</P>

Low Genetic Diversity and Shallow Population Structure of the Japanese Halfbeak Hyporhamphus Sajori Revealed from Mitochondrial DNA in the Northeast Asia

곽우석,Qun Zhang,Animesh Roy 한국어류학회 2019 韓國魚類學會誌 Vol.31 No.4

This study was conducted to know the genetic diversity and population structure of Japanese halfbeak (Hyporhamphus sajori) in the Northeast Asia, using mitochondrial DNA control region. In the present study, a total of 70 individuals were collected from three locations of China (Liaoning), Korea (Tongyeong) and Japan (Wakasa Bay), and 47 individuals sequences from three locations of Japan (Wakasa Bay, Toyama Bay and Mikawa Bay) were downloaded from genbank. A total of 7 haplotypes were identified with 7 polymorphic sites from 358 bp length sequences. Haplotype and nucleotide diversity were very low and ranged from 0 to 0.295±0.156 and 0 to 0.0009±0.0011, respectively. Ancestral haplotype was shared by 94% individuals. An extremely low haplotype and nucleotide diversity, and starlike minimum spanning tree indicated that the species have undergone a recent population expansion after bottleneck. Pairwise FST values were low and there was no significant differences among populations suggesting a gene flow among the populations. Dispersal of the eggs with the aid of drifting seaweed and currents might be the major responsible factor for the genetic homogeneity.

Hierarchical free-standing networks of MnCo2S4 as efficient Electrocatalyst for oxygen evolution reaction

Harsharaj S. Jadhav,ROY ANIMESH,Gaurav M. Thorat,정욱진,서정길 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.71 No.-

The development of highly efficient, stable and cost-effective electrocatalyst for oxygen evolutionreaction (OER) is critical. Herein, we report growth of MnCo2S4 flakes on SS-mesh using two-stepstrategy, and used as an efficient, highly active and stable electrocatalyst for OER under alkalinecondition. The free-standing electrocatalyst delivers exceptional stability of 100 h and activity for OERwith overpotential of 290 mV at a current density of 10 mA cm 2 in 1 M KOH. The enhancedelectrocatalytic performance was supported experimentally by electrochemical impedance spectra andmeasurement of the electrochemically active surface area. The high electrochemical active surface areaand electrical conductivity of MnCo2S4 flakes played an essential role in their high electrocatalyticperformance.

Growth of urchin-like ZnCo₂O₄ microspheres on nickel foam as a binder-free electrode for high-performance supercapacitor and methanol electro-oxidation

Jadhav, Harsharaj S.,Roy, Animesh,Chung, Wook-Jin,Seo, Jeong Gil Elsevier 2017 ELECTROCHIMICA ACTA Vol.246 No.-

<P><B>Abstract</B></P> <P>The spinel-type transition metal oxides play key role in realizing cost-effective energy storage systems by exhibiting outstanding electrochemical activity and stability. Free standing 3D hierarchical mesoporous ZnCo<SUB>2</SUB>O<SUB>4</SUB> microspheres are grown on nickel foam (NF) substrate using hydrothermal route followed by annealing treatment. 3D hierarchical mesoporous ZnCo<SUB>2</SUB>O<SUB>4</SUB> microspheres with high surface area and uniform mesoporous distribution exhibits high electrochemical performance. The ZnCo<SUB>2</SUB>O<SUB>4</SUB>/NF electrode material deliver superior specific capacitance of 1143Fg<SUP>−1</SUP> at a current density of 1.25Ag<SUP>−1</SUP> in aqueous 2M KOH solution and exhibits long-term cycling stability with specific capacitance of 880Fg<SUP>−1</SUP> after 6000 cycles at 12.5Ag<SUP>−1</SUP>. Furthermore, ZnCo<SUB>2</SUB>O<SUB>4</SUB>/NF electrode maintains current density upto 105Ag<SUP>−1</SUP> in 1M KOH mixed with 0.5M methanol when applied as electro-catalyst for methanol electro-oxidation. The high electrochemical performance is mainly attributed to faster ion/electron transfer and an enhanced electrochemical kinetics. The present simple, and cost-effective synthesis approach can open new era for large-scale applications of the novel materials for different electrochemical applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Urchin-like 3D ZnCo<SUB>2</SUB>O<SUB>4</SUB> directly grown on nickel foam by hydrothermal route. </LI> <LI> ZnCo<SUB>2</SUB>O<SUB>4</SUB> electrode shows superior electrochemical performance for supercapacitor. </LI> <LI> First report on ZnCo<SUB>2</SUB>O<SUB>4</SUB> use as an electro-catalyst for methanol electro-oxidation. </LI> <LI> ZnCo<SUB>2</SUB>O<SUB>4</SUB> possess high surface area with uniform mesoporous pore size distribution. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

An empirical study of the risk-benefit perceptions between the nuclear and non-nuclear groups towards the nuclear power plant in Bangladesh

Islam Md Shafiqul,Roy Swapnil,Alfee Sadia Lena,Pal Animesh 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.12

Public perception of benefit over risk is the de facto factor in planning, construction, operation, halting, or phaseout of a nuclear power plant in any country. Even if there are multiple pathways of perceiving risk/benefit among different stakeholders, the perception of nuclear and non-nuclear groups needs to be individually tracked to help understand sectoral influence. Related studies were basically performed between the STEM (Science, Technology, Engineering, and Mathematics) and non-STEM groups. However, there are no such studies between the nuclear and non-nuclear groups. This study investigated the risk-benefit perceptions between the nuclear group (N = 102) and the non-nuclear group (N = 467) using survey data to measure their stake and identify the underlying factors by validating the hypotheses, through descriptive analysis, and structural equation modeling (SEM). Results showed that risk perception is significantly high in the non-nuclear group (as the P-value is > 0.001 to <0.01) while the benefit perception is slightly low in the nuclear group (as the P-value is > 0.01 to <0.05). The non-nuclear group was significantly influenced by risk perception due to a lack of involvement in nuclear activities. Notably, the nuclear group is less interactive in disseminating nuclear energy benefits to the non-nuclear group. Surprisingly, misperceptions and lack of confidence about the benefits of nuclear energy also exist in the nuclear group. The study emphasizes debunking nuclear myths in the nuclear and non-nuclear groups through meaningful interactions and demands effective public awareness-building programs by competent authorities for the growth of the nuclear industry.

Low Genetic Diversity and Shallow Population Structure of the Japanese Halfbeak Hyporhamphus sajori Revealed from Mitochondrial DNA in the Northeast Asia

Gwak, Woo-Seok,Zhang, Qun,Roy, Animesh The Ichthyological Society of Korea 2019 韓國魚類學會誌 Vol.31 No.4

This study was conducted to know the genetic diversity and population structure of Japanese halfbeak (Hyporhamphus sajori) in the Northeast Asia, using mitochondrial DNA control region. In the present study, a total of 70 individuals were collected from three locations of China (Liaoning), Korea (Tongyeong) and Japan (Wakasa Bay), and 47 individuals sequences from three locations of Japan (Wakasa Bay, Toyama Bay and Mikawa Bay) were downloaded from genbank. A total of 7 haplotypes were identified with 7 polymorphic sites from 358 bp length sequences. Haplotype and nucleotide diversity were very low and ranged from 0 to 0.295±0.156 and 0 to 0.0009±0.0011, respectively. Ancestral haplotype was shared by 94% individuals. An extremely low haplotype and nucleotide diversity, and starlike minimum spanning tree indicated that the species have undergone a recent population expansion after bottleneck. Pairwise F_ST values were low and there was no significant differences among populations suggesting a gene flow among the populations. Dispersal of the eggs with the aid of drifting seaweed and currents might be the major responsible factor for the genetic homogeneity. 학꽁치(Hyporhamphus sajori)의 유전적 다양성과 집단구조를 조사하기 위해 동북아시아에서 시료를 채집하여 mitochondrial DNA control region (mtDNA CR)을 분석하였다. 시료는 중국(Liaoning), 한국(통영), 일본(Wakasa Bay) 3곳에서 총 70개체를 채집했고, 일본 3곳(Wakasa Bay, Toyama Bay and Mikawa Bay)에서 분석된 47개체의 mtDNA CR 염기서열을 Genbank에서 다운로드했다. 분석결과 총 358 bp가 나타났고, 7개의 변이와 함께 haplotype이 7개 확인되었다. Haplotype diversity과 nucleotide diversity는 각각 0~0.295±0.156 및 0~0.0009±0.0011이고, main haplotype을 94%의 개체가 공유했다. 매우 낮은 haplotype diversity와 nucleotide diversity 그리고 starlike minimum spanning tree는 집단이 최근에 병목현상을 거친 후, 팽창되었음을 나타낸다. 집단 간에 Pairwise F_ST 값은 낮고 유의하지 않은 것으로 나타났고, 이것은 집단 간 gene flow가 있음을 시사한다. 학꽁치의 genetic homogenity는 부유조와 해류가 주요 원인으로 생각된다.