The near equimolar and non-equimolar high entropy alloys (HEAs) having five or more major components along with their mingled sites over the surface have made them unique materials for various ...catalytic reactions involving renewable energies. HEAs provide a platform to tune the surface microstructure and chemistry by selecting and controlling the elements, opening up vistas to design new materials for catalysis. The present perspective aims to provide the correlation between HEAs' structure and catalytic performance in various applications with views on challenges and unique opportunities. The scientific and technological curiosity needs to dig deep into the multicomponent phase space to discover various new materials with unique catalytic properties.
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•HEAs provide a platform to tune the surface microstructure and chemistry by selecting and controlling the elements, opening up vistas to design new materials for catalysis.•The present perspective aims to provide the correlation between the structure and catalytic performance of HEAs in various applications with views on challenges and unique opportunities.•The scientific and technological curiosity needs to dig deep into the multicomponent phase space to discover various new materials with unique catalytic properties.
Industrialization harms the quality of water; therefore, cleaning and monitoring water sources are essential for sustainable human health and aquatic life. An increase in active surface area and ...porosity can result in quick and efficient cleaning activity. 3D printing can build porous architecture with controlled porosity and active surface area. Here, catalytically active ZnO nanosheets were grown on the surface of 3D printed architecture (Schwarzites and Weissmuller) with different porosity and surface area. The Weissmuller structure along with ZnO, has shown better catalytic performance due to its higher porosity (~69%) and high active surface area, compared to Schwarzites structure. Synergistic effect of adsorption and photodegradation has resulted in ~95% removal efficiency of mixed dye within 10 min by Weissmuller structure. The dye degradation efficiency was determined using colorimetric measurements with a regular smartphone for real-time quantitative investigation of dye removal efficiency. Most importantly, decorated 3D printed structures exhibit high structural stability without residuals (ZnO nanosheets) in water after performing the recycling experiment. Therefore, the decorated 3D printing structures and colorimetric detection method will offer a user-friendly versatile technique for analysis of removal efficiency of toxic components in different polluted water sources without using high-end sophisticated instruments and complicated procedures.
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•3D printed polymer scaffold with different geometry and surface porosity.•In situ growth of ZnO nanoflakes on 3D printed scaffolds.•The synergistic effect between the photodegradation and adsorption in a one system.•Smartphone-based user-friendly facile detection of dye removal efficiency.•RGB calculation for quantitative analysis using colorimetric absorption technique.
Hybrid oxidation methodologies (HOMs) and active site enrichment of 2D nanocatalyst through defects induction are ubiquitously used for generating adequate reactive oxygen species (ROS) in ...synergistic decontamination of nano hazards. In this study, 2D graphitic carbon nitride (2D-gCN), synthesized through a single-step liquid exfoliation methodology, depicts a tensile strain-induced planar defect intensified structure, as comprehended from microscopic, spectroscopic, diffraction, and photo-electrochemical (PEC) studies. Also, the piezo-photocatalytic capability of degrader 2D-gCN is revealed through a rapid removal of several noxious organic pollutants, i.e., methylene blue (MB, 97% in 16 min), bromophenol blue (BB, 88% in 16 min), and ampicillin (AMP, 75%, in 120 min) in a controlled catalytic condition. Rates for MB, BB, and AMP piezo-photo-dismissals are respectively ~ 16.4, 9.4, and 3.4 times higher than sole photocatalysis. The dismissal pathway consists of band bending through photon-aided piezo-cavitation, which leads to maximum ROS production and recombination suppression. Furthermore, LC–MS analysis confirms AMP remediation. In radicals trapping, OH, h
+
, and O
2
.−
are predominantly accountable for the AMP, BB, and MB dismissal, respectively. The piezo-photocatalytic stability has been assured through the morphological and bond characteristics of reusable 2D-gCN. So, using the HOM approach, 2D-gCN can be projected as a proficient remediator in wastewater treatments.
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•Defects are strengthened through Gd ions chemisorption onto 2D-gCN electrode.•XPS, SBET, and HR-TEM findings assure the lattice defects of Gd3+/2D-gCN NSs.•Nyquist and Bode plots ...exhibit the capacitive nature of the electrodes.•Ion’s intercalation leads to enhance the areal capacitance via EDLC mechanism.•Complete retention of Csp (2.59 mF cm−2) over 1000th cycles for Gd3+/2D-gCN NSs.
Thiswork reveals a facile synthesis of gadolinium ions adsorbed 2D-graphitic carbon nitride nanosheets (Gd3+/2D-gCN NSs) via a chemical-adsorption method for supercapacitor electrode materials. The structural, microstructural, and electrochemical properties ofGd3+/2D-gCN NSs and pristine 2D-gCN NSs are ascertained.The calculated capacitance for Gd3+/2D-gCN NSs is almost three times higher than the pristine one. The Nyquist and Bode plots exhibit thecapacitancemechanism.Gd+intercalation between the electrical double layers of adjacent 2D-gCN nanosheets increase the Van der Waals gap, which enhances it's specific capacitance. There is almost 100% retention of capacitance for Gd3+/2D-gCN NSs based device over 1000thcycle.
•A promising and sustainable solution using green additives for anticorrosive coating on carbon steel.•Influence of green graphene mixed with bitumen coating improves corrosion resistance property ...(99.5%).•Green graphene and bitumen coating improves, hydrophobicity, and nano-hardness of composite coating.
Here, we present the utilization of sustainable silica-rich green graphene (GG), obtained from the pyrolysis of remnant agricultural biomass (RAB), to enhance the corrosion-resistant properties of bitumen-modified coatings on carbon steel. Potentiodynamic polarization (PDP) analysis of GG-modified bitumen coatings exhibited higher corrosion resistance compared to uncoated steel, along with improved nano-hardness and hydrophobicity. The chemical interactions and barrier properties of GG-modified coatings hinder corrosive species ingress on to the metal surface, offering a sustainable, cost-effective solution for advanced corrosion-resistant coating material onunderground pipelines in marine environment.
We present a brief review and perspective on the development of eutectic alloys, emphasizing the emergence of complex microstructures during eutectic solidification of ternary and higher-order ...multicomponent alloys. Such alloys' abundant existence promises a large domain in the alloy development space for newer materials suitable for high-temperature applications. Hence the review explores these developments in eutectic alloys based on aluminum, titanium, nickel, intermetallics, and recently developed high entropy alloys. While the importance of fundamental understanding and various functional properties of the eutectic alloys cannot be ignored, this paper focuses primarily on the microstructure and their mechanical properties. The possibilities of ultrafine eutectics and multiscale variation of length scale and morphologies are emphasized. It highlights the potential for the future emergence of these alloys as high-strength structural materials for engineering applications.
Rapid depletion of non–renewable sources has made us look into possible green energy alternatives to meet energy challenges. Electrocatalytic reactions involving oxygen evolution reaction (OER) and ...oxygen reduction reaction (ORR) play crucial roles in assisting the derivation of clean forms of energy. Here, we demonstrate that few layers of the manganese oxide: hausmannitene (atomically thin two dimensional (2D-Mn3O4) can be exfoliated from its bulk form hausmannite (Mn3O4). Most significantly, the hausmannitene exhibits catalytic activity towards oxygen reduction and evolution reactions. The hausmannitene has enhanced Mn(III) ions (∼65%) compared to its parent structure hausmannite (∼31%). The Mn(III) ions in a distorted lattice show the highest catalytic activity towards OER performance with the oxygen electrode activity (ΔE) of 1.08 eV for hausmannitene. The density functional theory (DFT) calculations, confirmed the presence of both Mn(III) and Mn(II) sites on the (112)-oriented surface of Mn3O4 which are highly active for OER and ORR, having vacant and filled orbitals of lowest and highest energy, respectively. Increased oxidation sites aiding to better performance of 2D structure was theoretically manifested. Therefore, demonstrating that similar mechanisms can be used to explore other 2D oxides as possible efficient stable electrocatalyst substitute for energy conversion.
Conversion of carbon dioxide into selective hydrocarbon using a stable catalyst remains a holy grail in the catalysis community. The high overpotential, stability, and selectivity in the use of a ...single-metal-based catalyst still remain a challenge. In current work, instead of using pure noble metals (Ag, Au, and Pt) as the catalyst, a nanocrystalline high-entropy alloy (HEA: AuAgPtPdCu) has been used for the conversion of CO2 into gaseous hydrocarbons. Utilizing an approach of multimetallic HEA, a faradic efficiency of about 100% toward gaseous products is obtained at a low applied potential (−0.3 V vs reversible hydrogen electrode). The reason behind the catalytic activity and selectivity of the high-entropy alloy (HEA) toward CO2 electroreduction was established through first-principles-based density functional theory (DFT) by comparing it with the pristine Cu(111) surface. This is attributed to the reversal in adsorption trends for two out of the total eight intermediates*OCH3 and *O on Cu(111) and HEA surfaces.
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Two-dimensional (2D) materials are at the forefront of current materials research due to their exciting and unique properties. 2D tellurides are emerging materials which are yet to be ...fully explored. To provide an overview of this emergent field, in this review, we discuss the structure, properties, synthesis methods, and applications of selected 2D tellurides, with stoichiometry of MxTey, and MxNyTez, (M, N are metal atoms). We present a summary of the latest advances in modeling, experimental synthesis, and characterization of 2D tellurides. Additionally, stress and strain-induced tunability of the physical properties have been reviewed, with a focus on the application of 2D tellurides in electronic, optoelectronic, and magnetic devices. We have discussed many emergent quantum properties of these materials. Finally, we conclude with a perspective on the future of 2D metal tellurides.
Although direct methanol fuel cell offers high energy use efficiency and low pollution emission, the lack of suitable electrode materials poses a great challenge to its commercial application. ...Herein, a facile and scalable approach is developed to fabricate a hybrid electrocatalyst consisting of strongly coupled worm‐shape Pt nanocrystals and nitrogen‐doped low‐defect graphene (N‐LDG) sheets. Interestingly, it is found that the formation of Pt nanoworms (NWs) is induced by the N atoms in the high‐quality carbon matrix, which also allows the integration of their respective structural advantages and leads to a strong synergetic coupling effect. As a result, the obtained Pt NW/N‐LDG catalyst exhibits an extremely high mass activity of 1283.1 mA mg−1 toward methanol oxidation reaction, accompanied by reliable long‐term stability and good antipoisoning ability, which are dramatically enhanced as compared with conventional Pt nanoparticle catalysts dispersed on undoped LDG, reduced graphene oxide, and commercial carbon black supports.
The growth of Pt nanoworms on nitrogen‐doped low‐defect graphene is achieved by a combined CVD, heat treatment, and solvothermal method. Owing to the prominent structural features including large surface areas, well‐preserved pristine graphene structure, presence of catalytically active N atoms, and interconnected worm‐shape Pt configuration, the resulting hybrid is endowed with exceptional electrochemical properties toward methanol oxidation reaction.
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