Electronegativity Assisted Synthesis of Magnetically Recyclable Ni/NiO/g-C3N4 for Significant Boosting H2 Evolution

A magnetically recyclable Ni/NiO/g-C3N4 photocatalyst with significantly enhanced H2 evolution efficiency was successfully synthesized by a simple ethanol-solvothermal treatment. The presence of electronegative g-C3N4 is found to be the key factor for Ni0 formation in ternary Ni/NiO/g-C3N4, which provides anchoring sites for Ni2+ absorption and assembling sites for Ni0 nanoparticle formation. The metallic Ni0, on one side, could act as an electron acceptor enhancing carrier separation and transfer efficiency, and on the other side, it could act as active sites for H2 evolution. The NiO forms a p–n heterojunction with g-C3N4, which also promotes carrier separation and transfer efficiency. The strong magnetic property of Ni/NiO/g-C3N4 allows a good recyclability of catalyst from aqueous solution. The optimal Ni/NiO/g-C3N4 showed a full-spectrum efficiency of 2310 μmol·h−1·g−1 for hydrogen evolution, which is 210 times higher than that of pure g-C3N4. This ethanol solvothermal strategy provides a facile and low-cost synthesis of metal/metal oxide/g-C3N4 for large-scale application.

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Atomically dispersed nickel as coke-resistant active sites for methane dry reforming

Nature Communications ◽

10.1038/s41467-019-12843-w ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 46

Author(s):

Mohcin Akri ◽

Shu Zhao ◽

Xiaoyu Li ◽

Ketao Zang ◽

Adam F. Lee ◽

...

Keyword(s):

Active Sites ◽

Large Scale ◽

Low Cost ◽

Coke Formation ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Highly Active ◽

Catalytic Sites ◽

Earth Abundant ◽

Poor Stability

AbstractDry reforming of methane (DRM) is an attractive route to utilize CO2 as a chemical feedstock with which to convert CH4 into valuable syngas and simultaneously mitigate both greenhouse gases. Ni-based DRM catalysts are promising due to their high activity and low cost, but suffer from poor stability due to coke formation which has hindered their commercialization. Herein, we report that atomically dispersed Ni single atoms, stabilized by interaction with Ce-doped hydroxyapatite, are highly active and coke-resistant catalytic sites for DRM. Experimental and computational studies reveal that isolated Ni atoms are intrinsically coke-resistant due to their unique ability to only activate the first C-H bond in CH4, thus avoiding methane deep decomposition into carbon. This discovery offers new opportunities to develop large-scale DRM processes using earth abundant catalysts.

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Fe-Based Single-Atom Nanozyme with Superior Peroxidase-Mimicking Activity for Enhanced Ultrasensitive Biosensing

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19533 ◽

2021 ◽

Vol 21 (12) ◽

pp. 6126-6134

Author(s):

Lili Chi ◽

Yuetong Zhang ◽

Yusheng Hua ◽

Qiqi Xu ◽

Mingzhu Lv ◽

...

Keyword(s):

Active Sites ◽

Large Scale ◽

Low Cost ◽

Single Atom ◽

Specificity And Sensitivity ◽

Large Scale Preparation ◽

Species Formation ◽

Biomedical Diagnosis ◽

Scale Preparation

Nanomaterials with intrinsic enzyme-mimicking characteristics, refered to as nanozymes, have become a hot research topic owing to their unique advantages of comparative low cost, high stability and large-scale preparation. Among them, Single-atom nanozymes (SAzymes), as novel nanozymes with abundant atomically dispersed active sites, have caused specific attention in the development of nanozymes for their remarkable catalytic activities, maximum atomic utilization and excellent selectivity, the homogeneous catalytic sites and clear catalytic mechanisms. Herein, a novel single-atom nanozyme based on Fe(III)-doped polydiaminopyridine nanofusiforms (Fe-PDAP SAzyme) was successfully proposed via facile oxidation polymerization strategy. With well-defined coordination structure and abundant Fe-Nx active sites similar to natural metalloproteases, the Fe-PDAP SAzyme exhibits superior peroxidase-like activity by efficiently decomposing H2O2 for hydroxyl radical (.OH) species formation. Based on their superior peroxidase-like activity, colorimetric biosensing of H2O2 and glucose in vitro was performed by using a typical 3,3,5,5-tetramethylbenzidine through a multienzyme biocatalytic cascade platform, exhibiting the superior specificity and sensitivity. This work not only provides a novel promising SAzyme-based biosensor but also paves an avenue for evaluating enzyme activity and broadens the application of other nanozyme-based biosensors in the fields of biomedical diagnosis.

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Optimization of Oxygen Evolution Reaction with Electroless Deposited Ni–P Catalytic Nanocoating

Nanomaterials ◽

10.3390/nano11113010 ◽

2021 ◽

Vol 11 (11) ◽

pp. 3010

Author(s):

Sergio Battiato ◽

Mario Urso ◽

Salvatore Cosentino ◽

Anna Lucia Pellegrino ◽

Salvo Mirabella ◽

...

Keyword(s):

Oxygen Evolution ◽

Oxygen Evolution Reaction ◽

Active Sites ◽

High Performance ◽

Large Scale ◽

Low Cost ◽

Water Electrolysis ◽

Synthetic Approach ◽

Low Efficiency ◽

Electrochemical Water Splitting

The low efficiency of water electrolysis mostly arises from the thermodynamic uphill oxygen evolution reaction. The efficiency can be greatly improved by rationally designing low-cost and efficient oxygen evolution anode materials. Herein, we report the synthesis of Ni–P alloys adopting a facile electroless plating method under mild conditions on nickel substrates. The relationship between the Ni–P properties and catalytic activity allowed us to define the best conditions for the electroless synthesis of highperformance Ni–P catalysts. Indeed, the electrochemical investigations indicated an increased catalytic response by reducing the thickness and Ni/P ratio in the alloy. Furthermore, the Ni–P catalysts with optimized size and composition deposited on Ni foam exposed more active sites for the oxygen evolution reaction, yielding a current density of 10 mA cm−2 at an overpotential as low as 335 mV, exhibiting charge transfer resistances of only a few ohms and a remarkable turnover frequency (TOF) value of 0.62 s−1 at 350 mV. The present study provides an advancement in the control of the electroless synthetic approach for the design and large-scale application of high-performance metal phosphide catalysts for electrochemical water splitting.

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Experimental demonstration of a dispersive spectral splitting concentrator for high efficiency photovoltaics

MRS Advances ◽

10.1557/adv.2016.98 ◽

2016 ◽

Vol 1 (14) ◽

pp. 949-955 ◽

Cited By ~ 1

Author(s):

Carlo Maragliano ◽

Matteo Chiesa ◽

Marco Stefancich

Keyword(s):

Solar Cells ◽

Mass Production ◽

Large Scale ◽

High Efficiency ◽

Low Cost ◽

Electrical Power ◽

Optical Element ◽

Optical Transmittance ◽

Experimental Demonstration ◽

Full Spectrum

ABSTRACTWe report the experimental demonstration of a low-cost paradigm for photovoltaic power generation that utilizes a prismatic Fresnel-like lens to simultaneously concentrate and separate sunlight into laterally spaced spectral bands. The optical element is designed using geometric optics and optical dispersion and its performance is simulated with a ray-tracing software. The device, fabricated by injection molding, suitable for large-scale mass production, is experimentally characterized. We report an average optical transmittance above 85% over the VIS-IR range and spectral separation in excellent agreement with our simulations. Finally, the system is tested with a pair of copper indium gallium selenide based solar cells. We demonstrate an increase in peak electrical power output of 160% under outdoor sunlight illumination, corresponding to an increase in power conversion efficiency of 15% relative to single-junction full-spectrum one-sun illumination. Given the ease of manufacturability and the potential of the proposed solution, we project that our design can provide a cost-effective alternative to multi-junction solar cells ready for mass production.

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Inexpensive Organic Materials and Their Applications towards Heavy Metal Attenuation in Waters from Southern Peru

Water ◽

10.3390/w12102948 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2948

Author(s):

Pablo Garcia-Chevesich ◽

Vilma García ◽

Gisella Martínez ◽

Julia Zea ◽

Juana Ticona ◽

...

Keyword(s):

Water Reuse ◽

Active Sites ◽

Large Scale ◽

Organic Materials ◽

Material Selection ◽

Low Cost ◽

Sorption Isotherms ◽

Developing Regions ◽

Bacteria And Fungi ◽

Contaminant Release

There is interest in using locally available, low cost organic materials to attenuate heavy metals such as Cd, Cr, Cu, Hg, Ni, Pb, and Zn found in surface waters in Peru and other developing regions. Here we mesh Spanish language publications, archived theses, and prior globally available literature to provide a tabulated synthesis of organic materials that hold promise for this application in the developing world. In total, nearly 200 materials were grouped into source categories such as algae and seashells, bacteria and fungi, terrestrial plant-derived materials, and other agricultural and processing materials. This curation was complemented by an assessment of removal potential that can serve as a resource for future studies. We also identified a subset of Peruvian materials that hold particular promise for further investigation, including seashell-based mixed media, fungal blends, lignocellulose-based substrates including sawdust, corn and rice husks, and food residuals including peels from potatoes and avocadoes. Many studies reported percent removal and/or lacked consistent protocols for solid to liquid ratios and defined aqueous concentrations, which limits direct application. However, they hold value as an initial screening methodology informed by local knowledge and insights that could enable adoption for agriculture and other non-potable water reuse applications. While underlying removal mechanisms were presumed to rely on sorptive processes, this should be confirmed in promising materials with subsequent experimentation to quantify active sites and capacities by generating sorption isotherms with a focus on environmental conditions and specific contaminated water properties (pH, temperature, ionic strength, etc.). These organics also hold promise for the pairing of sorption to indirect microbial respiratory processes such as biogenic sulfide complexation. Conversely, there is a need to quantify unwanted contaminant release that could include soluble organic matter and nutrients. In addition to local availability and treatment efficacy, social, technical, economic, and environmental applicability of those materials for large-scale application must be considered to further refine material selection.

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On Matrix Completion-Based Channel Estimators for Massive MIMO Systems

Symmetry ◽

10.3390/sym11111377 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1377

Author(s):

Mingjun Ding ◽

Xiaodong Yang ◽

Rui Hu ◽

Zhitao Xiao ◽

Jun Tong ◽

...

Keyword(s):

Computational Complexity ◽

Massive Mimo ◽

Communication Systems ◽

Large Scale ◽

Hybrid Methods ◽

Mimo Systems ◽

Low Cost ◽

Matrix Completion ◽

Spectrum Efficiency ◽

Robust Solution

Large-scale symmetric arrays such as uniform linear arrays (ULA) have been widely used in wireless communications for improving spectrum efficiency and reliability. Channel state information (CSI) is critical for optimizing massive multiple-input multiple-output(MIMO)-based wireless communication systems. The acquisition of CSI for massive MIMO faces challenges such as training shortage and high computational complexity. For millimeter wave MIMO systems, the low-rankness of the channel can be utilized to address the challenge of training shortage. In this paper, we compared several channel estimation schemes based on matrix completion (MC) for symmetrical arrays. Performance and computational complexity are discussed and compared. By comparing the performance in different scenarios, we concluded that the generalized conditional gradient with alternating minimization (GCG-Alt) estimator provided a low-cost, robust solution, while the alternating direction method of multipliers (ADMM)-based hybrid methods achieved the best performance when the array response was perfectly known.

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Toward a low-cost disdrometer: simulating the collision of raindrops with a cantilever piezo film

10.5194/egusphere-egu21-10785 ◽

2021 ◽

Author(s):

Chi-Ling Wei ◽

Wei-Jiun Su ◽

Shu-Wei Chang ◽

Li-Pen Wang

Keyword(s):

Large Scale ◽

Low Cost ◽

Single Drop ◽

Laser Technologies ◽

Raindrop Size Distribution ◽

Proposed Model ◽

Key Factor ◽

Radar Echo ◽

Series Of Experiments ◽

Raindrop Size

<p>Raindrop size distribution (DSD) is the key factor to derive reliable rainfall estimates. It is strongly related to a number of integral rainfall parameters, including rain intensity (R), rain water content (W) and radar echo (Z). Disdrometers are the senors commonly used to measure DSD based upon microwave or laser technologies; such as JWD (Joss-Waldvogel Disdrometer), Parsivel and 2DVD (Two-Dimensional Video Disdrometer). These sensors have different strengths and weakness, and they are relatively expensive. This hinders the possibility to have a large-scale and high-density observation of DSD. In this work, our goal is to explore the possibility to develop a lightweight and low-cost disdrometer with high accuracy.</p><p>We start with establish a model that can well simulate the signal reaction of a single drop falling on a cantilever piezo film. A series of experiments were conducted to test the reaction of drops with different sizes (diameters ranging from 2 - 4 mm) and as drops falling onto different locations of the film. We then modelled the collision by assuming the piezo film to be a damped cantilever beam and drop force to be a step force; and the drop force is derived based upon the measurement of the deflection of beam end, which is further used to fit the damp ratio. Preliminary results suggest that the signal reaction of a single drop hits can be well simulated based upon the proposed model under current experimental setting. More experiments and simulations are currently undergoing to explore the capacity of the proposed model with different drop falling velocity, size and position, as well as its reaction of multiple drops. &#160;</p>

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Going the Distance

10.23943/princeton/9780691150772.001.0001 ◽

2020 ◽

Author(s):

Ron Harris

Keyword(s):

Large Scale ◽

Western Europe ◽

Family Firms ◽

Global Trade ◽

Long Distance ◽

Business Corporation ◽

Modern Economy ◽

Key Factor ◽

Silk Route ◽

Passive Investors

Before the seventeenth century, trade across Eurasia was mostly conducted in short segments along the Silk Route and Indian Ocean. Business was organized in family firms, merchant networks, and state-owned enterprises, and dominated by Chinese, Indian, and Arabic traders. However, around 1600 the first two joint-stock corporations, the English and Dutch East India Companies, were established. This book tells the story of overland and maritime trade without Europeans, of European Cape Route trade without corporations, and of how new, large-scale, and impersonal organizations arose in Europe to control long-distance trade for more than three centuries. It shows that by 1700, the scene and methods for global trade had dramatically changed: Dutch and English merchants shepherded goods directly from China and India to northwestern Europe. To understand this transformation, the book compares the organizational forms used in four major regions: China, India, the Middle East, and Western Europe. The English and Dutch were the last to leap into Eurasian trade, and they innovated in order to compete. They raised capital from passive investors through impersonal stock markets and their joint-stock corporations deployed more capital, ships, and agents to deliver goods from their origins to consumers. The book explores the history behind a cornerstone of the modern economy, and how this organizational revolution contributed to the formation of global trade and the creation of the business corporation as a key factor in Europe's economic rise.

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An Assessment of a Low-Cost Wastewater Disposal System after Twenty-Five Years of Operation

Water Science & Technology ◽

10.2166/wst.1987.0249 ◽

1987 ◽

Vol 19 (5-6) ◽

pp. 701-710 ◽

Cited By ~ 3

Author(s):

B. L. Reidy ◽

G. W. Samson

Keyword(s):

Large Scale ◽

Low Cost ◽

Wastewater Disposal ◽

Industrial Base ◽

Industrial Wastewaters ◽

The Past ◽

Gasification Process ◽

Appropriate Treatment ◽

Environmentally Safe ◽

Coal Resource

A low-cost wastewater disposal system was commissioned in 1959 to treat domestic and industrial wastewaters generated in the Latrobe River valley in the province of Gippsland, within the State of Victoria, Australia (Figure 1). The Latrobe Valley is the centre for large-scale generation of electricity and for the production of pulp and paper. In addition other industries have utilized the brown coal resource of the region e.g. gasification process and char production. Consequently, industrial wastewaters have been dominant in the disposal system for the past twenty-five years. The mixed industrial-domestic wastewaters were to be transported some eighty kilometres to be treated and disposed of by irrigation to land. Several important lessons have been learnt during twenty-five years of operating this system. Firstly the composition of the mixed waste stream has varied significantly with the passage of time and the development of the industrial base in the Valley, so that what was appropriate treatment in 1959 is not necessarily acceptable in 1985. Secondly the magnitude of adverse environmental impacts engendered by this low-cost disposal procedure was not imagined when the proposal was implemented. As a consequence, clean-up procedures which could remedy the adverse effects of twenty-five years of impact are likely to be costly. The question then may be asked - when the total costs including rehabilitation are considered, is there really a low-cost solution for environmentally safe disposal of complex wastewater streams?

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Rapid, large-scale species discovery in hyperdiverse taxa using 1D MinION sequencing

BMC Biology ◽

10.1186/s12915-019-0706-9 ◽

2019 ◽

Vol 17 (1) ◽

Cited By ~ 17

Author(s):

Amrita Srivathsan ◽

Emily Hartop ◽

Jayanthi Puniamoorthy ◽

Wan Ting Lee ◽

Sujatha Narayanan Kutty ◽

...

Keyword(s):

Dna Sequences ◽

Large Scale ◽

Low Cost ◽

Small Body ◽

Small Subset ◽

Similar Species ◽

Large Species ◽

Morphological Examination ◽

Species Discovery ◽

Short Period

Abstract Background More than 80% of all animal species remain unknown to science. Most of these species live in the tropics and belong to animal taxa that combine small body size with high specimen abundance and large species richness. For such clades, using morphology for species discovery is slow because large numbers of specimens must be sorted based on detailed microscopic investigations. Fortunately, species discovery could be greatly accelerated if DNA sequences could be used for sorting specimens to species. Morphological verification of such “molecular operational taxonomic units” (mOTUs) could then be based on dissection of a small subset of specimens. However, this approach requires cost-effective and low-tech DNA barcoding techniques because well-equipped, well-funded molecular laboratories are not readily available in many biodiverse countries. Results We here document how MinION sequencing can be used for large-scale species discovery in a specimen- and species-rich taxon like the hyperdiverse fly family Phoridae (Diptera). We sequenced 7059 specimens collected in a single Malaise trap in Kibale National Park, Uganda, over the short period of 8 weeks. We discovered > 650 species which exceeds the number of phorid species currently described for the entire Afrotropical region. The barcodes were obtained using an improved low-cost MinION pipeline that increased the barcoding capacity sevenfold from 500 to 3500 barcodes per flowcell. This was achieved by adopting 1D sequencing, resequencing weak amplicons on a used flowcell, and improving demultiplexing. Comparison with Illumina data revealed that the MinION barcodes were very accurate (99.99% accuracy, 0.46% Ns) and thus yielded very similar species units (match ratio 0.991). Morphological examination of 100 mOTUs also confirmed good congruence with morphology (93% of mOTUs; > 99% of specimens) and revealed that 90% of the putative species belong to the neglected, megadiverse genus Megaselia. We demonstrate for one Megaselia species how the molecular data can guide the description of a new species (Megaselia sepsioides sp. nov.). Conclusions We document that one field site in Africa can be home to an estimated 1000 species of phorids and speculate that the Afrotropical diversity could exceed 200,000 species. We furthermore conclude that low-cost MinION sequencers are very suitable for reliable, rapid, and large-scale species discovery in hyperdiverse taxa. MinION sequencing could quickly reveal the extent of the unknown diversity and is especially suitable for biodiverse countries with limited access to capital-intensive sequencing facilities.

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