•Novel SiC/Pyrrolic-N doped carbon material have been synthesized from bamboo.•Inherent SiO2 moieties in natural bamboo has been used as a sacrificial template.•The synergy of SiC and Pyrrolic-N has ...been demonstrated for Faradaic redox reactions.•Natural bamboo-based carbon materials deliver capacitance of 369 F g−1 at 0.5 A g−1.•Bamboo-based carbon materials deliver 100% capacitance retention after 5000 cycles.
It is still challenging to prepare porous carbon materials following a facile, green and universal sacrificial template method from renewable biomass. For this purpose, bio-renewable bamboo is a natural silicon reservoir containing a significant amount of inherent silica that can act as a natural sacrificial template for the formation of porous carbon materials as well as a dopant. Herein, we firstly report the SiC/N dual doped bio-renewable carbon material via a facile, natural sacrificial template method. In this newly developed method, the inherently available SiO2 nanoparticles have been utilized as the natural sacrificial template for creating the multi-porous architecture as well as for the generation of structural defects in the form of SiC nano-species. Additionally, the inherent nitrogen functional groups give rise to the formation of only pyrrolic-N species after pyrolysis. Furthermore, dual doping of SiC and pyrrolic-N species stimulate the faradaic redox reaction during the charge/discharge process and further increase the rate capability at higher current density with excellent electrochemical stability. Hence, the synergistic effect of SiC and N-pyrrolic dually doped carbon network gives rise to the formation of promising electrode material towards supercapacitors. Benefiting from the above unique features, the supercapacitor with the SNAC-1 electrode material delivers excellent capacitive behavior (369 F g−1 at 0.5 A g−1) in 1 M H2SO4 electrolyte with 100% capacitance retention after 5000 charge–discharge cycles. More prominently, the all-solid state, symmetric supercapacitors assembled by SNAC-1 show outstanding capacitance of 162 F g−1 at 0.5 A g−1 and reveal high energy density (∼5.41 W h kg−1 at 0.5 kW kg−1 power density) and excellent cyclic stability. This work provides an ideal sustainable solution from bamboo source to prepare porous SiC/N composites for cost-effective supercapacitor’s electrode materials.
Photocatalytic degradation of dye and phenolic compounds as textile effluent using UV- TiO2 photocatalysis based on color removal.
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•TiO2 is used as a semiconductor photocatalyst in ...presence of UV light.•TiO2 photocatalytic advanced oxidation process is executed by five steps.•Metal and non-metal co-doping on TiO2 can increase photocatlytic performance.•UV- doped TiO2 photocatalysis is able to mineralize toxic dyes and phenolic compounds.
Treatment of textile wastewater using titanium dioxide (TiO2) photocatalysis has been started from the last decade and reached attention to the researchers because of its versatile application. The variety of applications of TiO2 as a photocatalyst has been taken place because of low operating temperature, biologically inert nature, low energy consumption, water insolubility, ease availability and photoactivity, less toxicity, high chemical stability, suitable flat band potential, narrow band gap and environmentally benign. The successful and efficient application of photocatalysis depends on quality of photocatalyst, nature of pollutants, and source of light, which should be in close contact with each other. The TiO2 photocatalyst is used for the effluent treatment of textile wastewater in the presence of ultraviolet (UV) irradiation. Heterogeneous UV-TiO2 photocatalysis is capable to remove organic pollutants from textile wastewater, which has been widely studied and the technology also being commercialized in many developing countries in the world. This review focuses on the mechanism of UV-TiO2 photocatalysis, modification of TiO2 photocatalyst, and application of doping and co-doping in order to improve the photocatalytic activity in wastewater treatment. In addition, the review conveys comprehensive and fundamental assessments of the photocatalytic activity for the removal of organic dyes and phenolic compounds from textile wastewater.
Molecular sequential doping using conjugated polymers is a promising approach to modulate or improve electrical conductivity without sacrificing the morphology of a pristine polymer film. In article ...number 2005129, Hyungtak Seo, Jong H. Kim, Bong‐Gi Kim, and co‐workers develop a cascade doping strategy that realizes excellent electrical conductivity through a separated doping process using two different dopants. The first dopant provides a kinetically favorable working environment for the second dopant, through regeneration, reengagement, and replacement during the secondary doping step.
Since the properties of lead-free piezoelectric materials have thus far failed to meet those of lead-based materials, either chemical doping or morphological texturing should be employed to improve ...the piezoelectric properties of lead-free piezoelectric ceramics. The goal of this study was to synthesize plate-like K sub(1/2)Na sub(1/2)NbO sub(3) and NaNbO sub(3) particles, which are the most favorable templates for morphological texturing of K sub(1/2)Na sub(1/2)NbO sub(3) ceramics. To achieve this goal, Bi sub(2.5)Na sub(3.5)Nb sub(5)O sub(18) precursors in a plate-like shape were first synthesized and subsequently converted into K sub(1/2)Na sub(1/2)NbO sub(3) or NaNbO sub(3) particles that retain the morphology of Bi sub(2.5)Na sub(3.5)Nb sub(5)O sub(18). In this study, we found that sodium or potassium carbonate does not play a major role in converting the Bi sub(2.5)Na sub(3.5)Nb sub(5)O sub(18) precursor to K sub(1/2)Na sub(1/2)NbO sub(3) or NaNbO sub(3), on the contrary to previous reports; however, the salt contributes to the conversion reaction. All synthesis processes have been performed via a molten salt method, and scanning electron microscopy, scanning probe microscopy, and inductively coupled plasma mass spectroscopy were used to characterize the synthesized K sub(1/2)Na sub(1/2)NbO sub(3) or NaNbO sub(3) templates.
Microwave doping of graphene by phosphorus and sulphur is demonstrated and their optical, optoelectronic, and magnetic behaviours have been explored.
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•Microwave doping of graphene is ...primarily graphitic.•Microwave doping of graphene by P ∼ 15 % and S ∼ 12.5 % is reported.•Microwave P- or S- doped graphene is magnetic at room temperature.•Ms for P- and S- doped graphene are ∼ 0.13 and 0.15 emu/g respectively.•Spin-polarized DFT establishes spin asymmetry caused by doping.
Graphene, sp2-hybridized miracle material of 21st century possesses extra-ordinary physico-chemical properties and hence inspires several salient frontline applications. Lack of magnetic ordering limits its dream spintronic chips applications. Phosphorus and sulfur being large and electron-rich atoms, if adequately doped to graphene, will enable carrier injection (worth for electronic chips) and net spin-polarized electrons (worth for spintronic chips) in it. However, in-plane (preferentially) ultra-doping of graphene by phosphorus and sulfur is extremely challenging by conventional techniques. We report microwave doping of graphene by phosphorus and sulfur atoms up to record doping level of 15 and 12.5 % respectively which render graphene room temperature ferromagnetism with a saturation magnetization as high as 0.13 emu/g and 0.15 emu/g for phosphorus and sulfur doping “respectively”. Spin-polarized DFT band structure calculations suggest vivid spin asymmetry caused by doping which supports our experimental findings of primarily graphitic doped samples. Microwave doping of graphene by phosphorus and sulfur brings in dramatic changes in its magnetic behaviour and thus the present research establishes it as a novel doping strategy with excellent efficiency, scalability, and reproducibility, and will inspire new generations of graphene-based spintronic chips.
A synergistic N doping plus PO43− intercalation strategy is used to induce high conversion (ca. 41 %) of 2H‐MoS2 into 1T‐MoS2, which is much higher than single N doping (ca. 28 %) or single PO43− ...intercalation (ca. 10 %). A scattering mechanism is proposed to illustrate the synergistic phase transformation from the 2H to the 1T phase, which was confirmed by synchrotron radiation and spherical aberration TEM. To further enhance reaction kinetics, the designed (N,PO43−)‐MoS2 nanosheets are combined with conductive vertical graphene (VG) skeleton forming binder‐free arrays for high‐efficiency hydrogen evolution reaction (HER). Owing to the decreased band gap, lower d‐band center, and smaller hydrogen adsorption/desorption energy, the designed (N,PO43−)‐MoS2/VG electrode shows excellent HER performance with a lower Tafel slope and overpotential than N‐MoS2/VG, PO43−‐MoS2/VG counterparts, and other Mo‐base catalysts in the literature.
An N‐doping plus PO43− intercalation strategy is used to induce high conversion (ca. 41 %) of 2H‐MoS2 into 1T‐MoS2, which is much higher than single N‐doping or PO43− intercalation (ca. 28 % and ca. 10 %, respectively). A scattering mechanism is proposed to illustrate the synergistic phase transformation from 2H phase to 1T phase, confirmed by synchrotron radiation and spherical aberration TEM.
Ultrathin NiMn-LDH nanosheets in situ grown on nickel foam are prepared, in which suitable dose of Mn doping can change the electronic configuration, construct special stacking fault disorder to ...alleviate undesired structural change and produce a new impurity band to enhance electronic conductivity. These merits make NiMn-LDH //AC achieve superior cycling performance of at high current density of 10 A g−1.
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•NiMn-LDH/NF possesses high specific capacity, excellent rate capability and superior cycling performance.•Mn-dopant improves electrochemical performance of α-Ni(OH)2 by special stacking fault disorder and changed band gap energy.•EXAFS data, XRD patterns and DFT calculations prove the novel stacking fault disorder between NiO2 slabs.
Mn-doping engineering route has been demonstrated an effective way to enhance the electronic conductivity of α-Ni(OH)2 as a hybrid supercapacitor electrode material. However, the problem of limited cycling lifetime remains unsolved and the structural evolution of Mn-doping at the atomic level is still under debate. Herein, a novel life span improving strategy is proposed to modulate the electronic configuration and the layer stacking mode of Mn doped Ni(OH)2 (NiMn-LDH) in situ grown on nickel foam by controlling the Mn doping level (~6% atomic) and occupied site (3a site only). XRD, EXAFS and DFT calculations have been employed to confirm that the modified electronic configuration due to Mn doping induces local contraction of metal-O/metal bond length and increases curve degree within ab planes, which further introduces special stacking fault disorder between layers to stabilize the structure. Finally, the suitable-dose Mn doped NiMn-LDH exhibits high capacity (1498 C g−1 at 2 A g−1), excellent rate capability and superior cycling performance (almost 100% capacity retention after 30,000 cycles at 50 A g−1). This work demonstrates modulating local environment by suitable dose of metal doping can boost the cycling performance of nickel-based electrode materials for applications in energy storage and conversion.
Gene doping: Present and future Cantelmo, Rebeca Araujo; da Silva, Alessandra Pereira; Mendes-Junior, Celso Teixeira ...
European journal of sport science,
September 2020, Letnik:
20, Številka:
8
Journal Article
Recenzirano
Being an elite athlete is an extremely coveted position, which can lead an individual to use doping. As knowledge is extended, doping techniques have become increasingly sophisticated, and the newest ...method of doping is gene doping. This article aims to present an updated bibliographic survey that addresses gene doping between 1983 and 2018. Anti-doping agencies have not yet approved any detection technique for this type of doping. The possibility of eradicating such doping is almost zero mainly because gene therapy advances rapidly. In this scenario, the future of gene doping must be discussed and decided before irreversible limits are exceeded.
Element doping allows manipulation of the electronic properties of 2D materials. Enhanced transport performances and ambient stability of black‐phosphorus devices by Te doping are presented. This ...provides a facile route for achieving airstable black‐phosphorus devices.
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