Limitations of the Tauc Plot Method

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(47)

Published: Sept. 3, 2023

Abstract The Tauc plot is a method originally developed to derive the optical gap of amorphous semiconductors such as germanium or silicon. By measuring absorption coefficient α ( hν ) and plotting versus photon energy , value for determined. In this way non‐direct transitions between approximately parabolic bands can be examined. last decades, modification (poly‐) crystalline has become popular study direct indirect interband transitions. For purpose, ahν n = 2) plotted against determine electronic bandgap . Due ease performing UV–vis measurements, nowadays standard analyze various solids, regardless their different structure. Although leads partially widely varying values respective nominally identical materials, there still no that critically questions which peculiarities in structure prevent use solids material classes applies. This aims close by discussing its limiting factors exemplary with structures.

Language: Английский

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Severe plastic deformation for producing superfunctional ultrafine-grained and heterostructured materials: An interdisciplinary review

Journal of Alloys and Compounds, Journal Year: 2024, Volume and Issue: 1002, P. 174667 - 174667

Published: May 9, 2024

Ultrafine-grained and heterostructured materials are currently of high interest due to their superior mechanical functional properties. Severe plastic deformation (SPD) is one the most effective methods produce such with unique microstructure-property relationships. In this review paper, after summarizing recent progress in developing various SPD for processing bulk, surface powder materials, main structural microstructural features SPD-processed explained including lattice defects, grain boundaries phase transformations. The properties potential applications then reviewed detail tensile properties, creep, superplasticity, hydrogen embrittlement resistance, electrical conductivity, magnetic optical solar energy harvesting, photocatalysis, electrocatalysis, hydrolysis, storage, production, CO2 conversion, corrosion resistance biocompatibility. It shown that achieving not limited pure metals conventional metallic alloys, a wide range processed by SPD, high-entropy glasses, semiconductors, ceramics polymers. particularly emphasized has moved from simple metal tool powerful means discovery synthesis new superfunctional nonmetallic materials. article ends declaring borders have been extended science it become an interdisciplinary address scientific questions as mechanism geological astronomical phenomena origin life.

Language: Английский

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Recent progress in defect‐engineered metal oxides for photocatalytic environmental remediation

Photochemistry and Photobiology, Journal Year: 2024, Volume and Issue: 100(4), P. 830 - 896

Published: May 16, 2024

Rapid industrial advancement over the last few decades has led to an alarming increase in pollution levels ecosystem. Among primary pollutants, harmful organic dyes and pharmaceutical drugs are directly released by industries into water bodies which serves as a major cause of environmental deterioration. This warns severe need find some sustainable strategies overcome these increasing eliminate pollutants before being exposed environment. Photocatalysis is well-established strategy field pollutant degradation various metal oxides have been proven exhibit excellent physicochemical properties makes them potential candidate for remediation. Further, with aim rapid industrialization photocatalytic technology, constant efforts made activity oxides. One such introduction defects lattice parent catalyst through doping or vacancy plays role enhancing catalytic achieving rates. review provides comprehensive analysis their altering material. Various defect-rich like binary oxides, perovskite spinel summarized application degradation. Finally, summary existing research, followed challenges along countermeasures provided pave path future studies this promising field.

Language: Английский

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Challenges in unconventional catalysis

Catalysis Today, Journal Year: 2023, Volume and Issue: 420, P. 114180 - 114180

Published: May 9, 2023

Catalysis science and technology increased efforts recently to progress beyond conventional "thermal" catalysis face the challenges of net-zero emissions electrification production. Nevertheless, a better gaps opportunities analysis is necessary. This review analyses four emerging areas unconventional or less-conventional which share common aspect using directly renewable energy sources: (i) plasma catalysis, (ii) for flow chemistry process intensification, (iii) application electromagnetic (EM) fields modulate catalytic activity (iv) nanoscale generation at catalyst interface strong local EM by plasmonic effect. Plasma has demonstrated synergistic effects, where outcome higher than sum both processes alone. Still, underlying mechanisms are complex, synergy not always obtained. There crucial need understanding design catalysts tailored environment, reactors with optimal transport species surface, tune conditions so they work in catalyst. Microfluidic (flow chemistry) another sector leading intensification syntheses, particularly organic chemistry. New must be designed exploit full novel possibilities. With focus on (a) continuous-flow photocatalysis, (b) electrochemical (c) microwave (d) ultrasound activation, series examples discussed, also indications scale-up industrialisation. The third area discussed regards effect performances applying oriented spanning several orders magnitude. Under well-defined conditions, gas breakdown and, some cases, formation generates activated phase species. field-driven chemical conversion depend further structured electric/magnetic catalysts, shape field strength direction. Different effects influencing have been reported, including reduced activation energy, surface charging, hot spot generation, selective heating. last topic complementary third, focusing possibility tuning photo- electro-catalytic properties creating localised electrical possibilities carriers generated discussed. thus aims stimulate reader make new, creative address reaching carbon-neutral world.

Language: Английский

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Improving photocatalytic oxidation of semiconductor (TiO2, SnO2, ZnO)/CNTs for NOx removal

Journal of Industrial and Engineering Chemistry, Journal Year: 2023, Volume and Issue: 127, P. 321 - 330

Published: July 12, 2023

Language: Английский

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Photodeposition‐Based Synthesis of TiO₂@IrO_x Core–Shell Catalyst for Proton Exchange Membrane Water Electrolysis with Low Iridium Loading

Advanced Science, Journal Year: 2024, Volume and Issue: 11(30)

Published: June 14, 2024

Abstract The widespread application of green hydrogen production technologies requires cost reduction crucial elements. To achieve this, a viable pathway to reduce the iridium loading in proton exchange membrane water electrolysis (PEMWE) is explored. Herein, scalable synthesis method based on photodeposition process for TiO 2 @IrO x core–shell catalyst with reduced content as low 40 wt.% presented. Using this method, titania support particles homogeneously coated thin oxide shell only 2.1 ± 0.4 nm are obtained. exhibits not high ex situ activity, but also decent stability compared commercially available catalysts. Furthermore, unique structure provides threefold increased electrical powder conductivity structures without shell. In addition, facilitates fabrication sufficiently thick layers at decreased loadings mitigating impact crack formation layer during PEMWE operation. It demonstrated that novel clearly outperforms commercial reference single‐cell tests an below 0.3 mg Ir cm −2 exhibiting superior iridium‐specific power density 17.9 kW g −1 10.4 reference.

Language: Английский

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Metal-organic framework (MOF)-based materials for photocatalytic antibacterial applications

Coordination Chemistry Reviews, Journal Year: 2024, Volume and Issue: 523, P. 216298 - 216298

Published: Nov. 6, 2024

Language: Английский

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Nanostructured CeO₂ photocatalysts: optimizing surface chemistry, morphology, and visible-light absorption

Nanoscale, Journal Year: 2024, Volume and Issue: 16(20), P. 9659 - 9679

Published: Jan. 1, 2024

Emerging photocatalytic applications of cerium dioxide (CeO

Language: Английский

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Photoelectrocatalytic activation of sulfate for sulfamethoxazole degradation and simultaneous H2 production by bifunctional N,P co-doped black-blue TiO2 nanotube array electrode

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 485, P. 149828 - 149828

Published: Feb. 19, 2024

Language: Английский

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Enhanced photocatalytic degradation of organic pollutants in water using copper oxide (CuO) nanosheets for environmental application

JCIS Open, Journal Year: 2024, Volume and Issue: 13, P. 100102 - 100102

Published: Jan. 7, 2024

Rapid, inexpensive, and low-power/solar light-driven photocatalytic degradation of organic pollutants to deal with annually produced trillion tons synthetic dye wastewater prevent water scarcity issues, ecotoxicological risks, human health has always been challenging. To overcome this limitation, the present study synthesized earth-abundant, inexpensive copper oxide nanosheets using a simple single-step hydrothermal route. The structural, physicochemical, functional properties have characterized several characterization techniques. activity was studied for two commonly industrially used dyes, Methylene Blue (MB) Rhodamine B (RhB). importance work is usage cheap commercially available Phillips UV light (11 W) as well direct sunlight. With optimized conditions, almost complete both dyes achieved within 35 minutes under low-power 70 by illumination natural enhanced performance can be correlated synergetic effect higher charge transfer mechanism, good catalytic 'active surface area' availability (13.2 m2/g), parameters that affect reaction efficacy. Additionally, five repeated uses without sacrificing confirmed their stability sustainability promising candidate large-scale industrial textile remedies.

Language: Английский

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