Read by QxMD icon Read


Alexis Grimaud, Oscar Diaz-Morales, Binghong Han, Wesley T Hong, Yueh-Lin Lee, Livia Giordano, Kelsey A Stoerzinger, Marc T M Koper, Yang Shao-Horn
Understanding how materials that catalyse the oxygen evolution reaction (OER) function is essential for the development of efficient energy-storage technologies. The traditional understanding of the OER mechanism on metal oxides involves four concerted proton-electron transfer steps on metal-ion centres at their surface and product oxygen molecules derived from water. Here, using in situ (18)O isotope labelling mass spectrometry, we provide direct experimental evidence that the O2 generated during the OER on some highly active oxides can come from lattice oxygen...
May 2017: Nature Chemistry
Dehua Xiong, Qingqing Zhang, Sitaramanjaneya Mouli Thalluri, Junyuan Xu, Wei Li, Xiuli Fu, Lifeng Liu
We report a very easy and cost-effective approach to the fabrication of monolithic Co9S8 water oxidation electrodes (Co@Co9S8), which is fabricated by one-step hydrothermal treatment of commercially available cobalt foam in the presence of thiourea. The morphology, crystal structure, microstructure, and composition of as-fabricated Co@Co9S8 electrodes are examined using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS), and their electrochemical properties are investigated by cyclic voltammetry (CV), chronopotentiometry (CP), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS)...
April 21, 2017: Chemistry: a European Journal
Yanyong Wang, Yiqiong Zhang, Zhijuan Liu, Chao Xie, Shi Feng, Dongdong Liu, Mingfei Shao, Shuangyin Wang
Layered double hydroxides (LDHs) with two-dimensional lamellar structures show excellent electrocatalytic properties. However, the catalytic activity of LDHs needs to be further improved as the large lateral size and thickness of the bulk material limit the number of exposed active sites. However, the development of efficient strategies to exfoliate bulk LDHs into stable monolayer LDH nanosheets with more exposed active sites is very challenging. On the other hand, the intrinsic activity of monolayer LDH nanosheets can be tuned by surface engineering...
April 21, 2017: Angewandte Chemie
Wan Li, Shilin Zhang, Qining Fan, Fazhi Zhang, Sailong Xu
Transition metal phosphide (TMP) nanostructures have stimulated increasing interest for use in water splitting owing to their abundant natural sources and high activity for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Typically, the preparation of hierarchical TMPs involves the utilization of expensive or dangerous phosphorus sources, and, in particular, the understanding of topotactic transformations of the precursors to crystalline phases-which could be utilized to enhance electrocatalytic performance-remains very limited...
April 20, 2017: Nanoscale
Zhiyi Lu, Guangxu Chen, Yanbin Li, Haotian Wang, Jin Xie, Lei Liao, Chong Liu, Yayuan Liu, Tong Wu, Yuzhang Li, Alan C Luntz, Michal Bajdich, Yi Cui
Identification of active sites for catalytic processes has both fundamental and technological implications for rational design of future catalysts. Herein, we study the active surfaces of layered lithium cobalt oxide (LCO) for the oxygen evolution reaction (OER) using the enhancement effect of electrochemical delithiation (De-LCO). Our theoretical results indicate that the most stable (0001) surface has a very large overpotential for OER independent of lithium content. In contrast, edge sites such as the nonpolar (112̅0) and polar (011̅2) surfaces are predicted to be highly active and dependent on (de)lithiation...
April 21, 2017: Journal of the American Chemical Society
Eduardo Vinuela, Eduardo A Vega, Suguru Yamashita, Marcel Sanhueza, Rosemarie Mege, Gabriel Cavada, Thomas A Aloia, Yun Shin Chun, Jeffrey E Lee, Jean-Nicolas Vauthey, Claudius Conrad
BACKGROUND: Gallbladder cancer detected incidentally after cholecystectomy (IGBC) currently is the most common diagnosis of gallbladder cancer, and oncologic extended resection (OER) is recommended for tumors classified higher than T1b. However, the precise prognostic significance of residual cancer (RC) found at the time of OER has not been well established. This analysis aimed to determine the prognostic impact of RC found in patients with IGBC undergoing OER. METHODS: Outcomes for IGBC at a center for a low-incidence country (USA) and a high-incidence country (Chile) between January 1999 and June 2015 were analyzed...
April 17, 2017: Annals of Surgical Oncology
Xueping Zhang, Liang Huang, Yujie Han, Miao Xu, Shaojun Dong
Developing efficient and earth-abundant oxygen evolution reaction (OER) electrocatalysts is of great importance in renewable energy research. Herein, we report nitrogen-doped carbon encapsulating γ-MoC/Ni heterostructures (γ-MoC/Ni@NC) for the first time as efficient OER electrocatalysts. The composites can be controlled by the addition of a Mo source to form a nanoparticle-assembled hierarchically porous nanostructure, which can enlarge the specific surface area, thus exposing more active sites. Moreover, we demonstrate that the formation of γ-MoC@Ni heterostructures and the resulting synergistic effect between γ-MoC and Ni can facilitate the reaction kinetics, leading to significantly improved OER activity with an onset overpotential of merely 240 mV, and a low overpotential of 310 mV to afford a current density of 10 mA cm(-2)...
April 13, 2017: Nanoscale
Seung Hyo Noh, Choah Kwon, Jeemin Hwang, Takeo Ohsaka, Beom-Jun Kim, Tae-Young Kim, Young-Gi Yoon, Zhongwei Chen, Min Ho Seo, Byungchan Han
In this study, we report self-assembled nitrogen-doped fullerenes (N-fullerene) as non-precious catalysts, which are active for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), and thus applicable for energy conversion and storage devices such as fuel cells and metal-air battery systems. We screen the best N-fullerene catalyst at the nitrogen doping level of 10 at%, not at the previously known doping level of 5 or 20 at% for graphene. We identify that the compressive surface strain induced by doped nitrogen plays a key role in the fine-tuning of catalytic activity...
April 13, 2017: Nanoscale
Chao Wei, Zhenxing Feng, Günther G Scherer, James Barber, Yang Shao-Horn, Zhichuan J Xu
Exploring efficient and low-cost electrocatalysts for the oxygen-reduction reaction (ORR) and oxygen-evolution reaction (OER) is critical for developing renewable energy technologies such as fuel cells, metal-air batteries, and water electrolyzers. A rational design of a catalyst can be guided by identifying descriptors that determine its activity. Here, a descriptor study on the ORR/OER of spinel oxides is presented. With a series of MnCo2 O4 , the Mn in octahedral sites is identified as an active site. This finding is then applied to successfully explain the ORR/OER activities of other transition-metal spinels, including Mnx Co3-x O4 (x = 2, 2...
April 10, 2017: Advanced Materials
Dengrong Sun, Lin Ye, Fangxiang Sun, Hermenegildo García, Zhaohui Li
Calcination of the mixed-metal species Co/Ni-MOF-74 leads to the formation of carbon-coated CoxNi1-x@CoyNi1-yO with a metal core diameter of ∼3.2 nm and a metal oxide shell thickness of ∼2.4 nm embedded uniformly in the ligand-derived carbon matrix. The close proximity of Co and Ni in the mixed-metal Co/Ni-MOF-74 promotes the metal alloying and the formation of a solid solution of metal oxide during the calcination process. The presence of the tightly coated carbon shell prohibits particle agglomeration and stabilizes the CoxNi1-x@CoyNi1-yO nanoparticles in small size...
April 7, 2017: Inorganic Chemistry
A S Schenk, S Eiben, M Goll, L Reith, A N Kulak, F C Meldrum, H Jeske, C Wege, S Ludwigs
Spinel-type Co3O4 finds applications in a wide range of fields, including clean energy conversion, where nanostructured Co3O4 may provide a cost-efficient alternative to platinum- and iridium-based catalysts for electrocatalytic water-splitting. We here describe a novel strategy in which basic cobalt carbonate - a precursor to Co3O4 - is precipitated as sheet-like structures and microspheres covered with fine surface protrusions, via ammonium carbonate decomposition at room temperature. Importantly, these mild reaction conditions enable us to employ bio-inspired templating approaches to further control the mineral structure...
April 7, 2017: Nanoscale
Tingting Zhou, Zhen Cao, Pan Zhang, Houyi Ma, Zhen Gao, Heng Wang, Yue Lu, Jia He, Yunfeng Zhao
Nickel-based hydroxide hierarchical nanoarrays (NiyM(OH)x HNAs M = Fe or Zn) are doped with non-noble transition metals to create nanostructures and regulate their activities for the oxygen evolution reaction. Catalytic performance in these materials depends on their chemical composition and the presence of nanostructures. These novel hierarchical nanostructures contain small secondary nanosheets that are grown on the primary nanowire arrays, providing a higher surface area and more efficient mass transport for electrochemical reactions...
April 6, 2017: Scientific Reports
A Younes, P Hilden, B Coiffier, A Hagenbeek, G Salles, W Wilson, J F Seymour, K Kelly, J Gribben, M Pfreunschuh, F Morschhauser, H Schoder, A D Zelenetz, J Rademaker, R Advani, N Valente, C Fortpied, T E Witzig, L H Sehn, A Engert, R I Fisher, P-L Zinzani, M Federico, M Hutchings, C Bollard, M Trneny, Y A Elsayed, K Tobinai, J S Abramson, N Fowler, A Goy, M Smith, S Ansell, J Kuruvilla, M Dreyling, C Thieblemont, R F Little, I Aurer, M H J Van Oers, K Takeshita, A Gopal, S Rule, S de Vos, I Kloos, M S Kaminski, M Meignan, L H Schwartz, J P Leonard, S J Schuster, V E Seshan
In recent years, the number of approved and investigational agents that can be safely administered for the treatment of lymphoma patients for a prolonged period of time has substantially increased. Many of these novel agents are evaluated in early-phase clinical trials in patients with a wide range of malignancies, including solid tumors and lymphoma. Furthermore, with the advances in genome sequencing, new "basket" clinical trial designs have emerged that select patients based on the presence of specific genetic alterations across different types of solid tumors and lymphoma...
April 3, 2017: Annals of Oncology: Official Journal of the European Society for Medical Oncology
Tran Ngoc Huan, Gwenaëlle Rousse, Sandrine Zanna, Ivan T Lucas, Xiangzhen Xu, Nicolas Menguy, Victor Mougel, Marc Fontecave
To use water as the source of electrons for proton or CO2 reduction within electrocatalytic devices, catalysts are required for facilitating the proton-coupled multi-electron oxygen evolution reaction (OER, 2 H2 O→O2 +4 H(+) +4 e(-) ). These catalysts, ideally based on cheap and earth abundant metals, have to display high activity at low overpotential and good stability and selectivity. While numerous examples of Co, Mn, and Ni catalysts were recently reported for water oxidation, only few examples were reported using copper, despite promising efficiencies...
April 4, 2017: Angewandte Chemie
Dong Un Lee, Jingde Li, Moon Gyu Park, Min Ho Seo, Wook Ahn, Ian Stadelmann, Luis Ricardez-Sandoval, Zhongwei Chen
The present work introduces spinel oxide nanocrystals self-assembled into mesoporous spheres that are bifunctionally active towards catalyzing both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). The electrochemical evaluation reveals that (Ni,Co)3 O4 demonstrates a significantly positive-shifted ORR onset and half-wave potentials [-0.127 and -0.292 V vs. saturated calomel electrode (SCE), respectively], whereas Co3 O4 results in a negative-shifted OER potential (0.65 V vs. SCE) measured at 10 mA cm(-2) ...
March 29, 2017: ChemSusChem
Wenjing Luo, Jun Hu, Hongling Diao, Benjamin Schwarz, Carsten Streb, Yu-Fei Song
The development of technologically viable electrodes for the electrochemical oxygen evolution reaction (OER) is a major bottleneck in chemical energy conversion. This article describes a facile one-step hydrothermal route to deposit microcrystals of a robust Dexter-Silverton polyoxometalate oxygen evolution catalyst, [Co6.8 Ni1.2 W12 O42 (OH)4 (H2 O)8 ], on a commercial nickel foam electrode. The electrode shows efficient and sustained electrochemical oxygen evolution at low overpotentials (360 mV at 10 mA cm(-2) against RHE, Tafel slope 126 mV dec(-1) , faradaic efficiency (96±5) %) in alkaline aqueous solution (pH 13)...
April 3, 2017: Angewandte Chemie
Xu Zou, Yipu Liu, Guo-Dong Li, Yuanyuan Wu, Da-Peng Liu, Wang Li, Hai-Wen Li, Dejun Wang, Yu Zhang, Xiaoxin Zou
Developing nonprecious oxygen evolution electrocatalysts that can work well at large current densities is of primary importance in a viable water-splitting technology. Herein, a facile ultrafast (5 s) synthetic approach is reported that produces a novel, efficient, non-noble metal oxygen-evolution nano-electrocatalyst that is composed of amorphous Ni-Fe bimetallic hydroxide film-coated, nickel foam (NF)-supported, Ni3 S2 nanosheet arrays. The composite nanomaterial (denoted as Ni-Fe-OH@Ni3 S2 /NF) shows highly efficient electrocatalytic activity toward oxygen evolution reaction (OER) at large current densities, even in the order of 1000 mA cm(-2) ...
March 29, 2017: Advanced Materials
Ju Seong Kim, Inchul Park, Eun-Suk Jeong, Kyoungsuk Jin, Won Mo Seong, Gabin Yoon, Hyunah Kim, Byunghoon Kim, Ki Tae Nam, Kisuk Kang
The development of a high-performance oxygen evolution reaction (OER) catalyst is pivotal for the practical realization of a water-splitting system. Although an extensive search for OER catalysts has been performed in the past decades, cost-effective catalysts remain elusive. Herein, an amorphous cobalt phyllosilicate (ACP) with layered crystalline motif prepared by a room-temperature precipitation is introduced as a new OER catalyst; this material exhibits a remarkably low overpotential (η ≈ 367 mV for a current density of 10 mA cm(-2) )...
March 29, 2017: Advanced Materials
Yanping Tang, Fan Jing, Zhixiao Xu, Fan Zhang, Yiyong Mai, Dongqing Wu
A bifunctional electrocatalyst for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly attractive for the manufacture of clean energy conversion devices. In this work, highly crumpled hybrid of nitrogen and sulfur dual-doped graphene and quasi-hexagonal Co9S8 nanoplates (Co9S8/NSGg-C3N4) is fabricated via a facile ionic assembly approach. The unique structure of Co9S8/NSGg-C3N4 renders it high specific surface area (288.3 m(2) g(-1)) and large pore volume (1.32 cm(3) g(-1)). As the electrocatalyst for ORR, Co9S8/NSGg-C3N4 demonstrates excellent performance with the onset potential of -0...
April 3, 2017: ACS Applied Materials & Interfaces
Jun Yang, Tsuyohiko Fujigaya, Naotoshi Nakashima
We present a new concept for homogeneous spinel nanocrystal-coating on high crystalline pristine-carbon nanotubes (CNTs) for efficient and durable oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Oxidized CNTs have widely been used to functionalize with metal or metal oxides since the defect sites act as anchoring for metal oxide binding. However, such defects on the tubes cause the decrease in electrical conductivity and stability, leading to lower catalyst performance. In the present study, at first, pristine multi-walled carbon nanotubes (MWNTs) were wrapped by pyridine-based polybenzimidazole (PyPBI) to which uniform NixCo3-xO4 nanocrystals were homogeneously deposited by the solvothermal method without damaging the MWNTs, in which PyPBI acted as efficient anchoring sites for the deposition of spinel oxide nanocrystals with ~5 nm size...
March 30, 2017: Scientific Reports
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"