Fig 4 - uploaded by Wang Yang
Content may be subject to copyright.
Source publication
Three-dimensional (3D) interconnected N-enriched hierarchical porous lamellar carbon (NPLC) with a multilevel pore structure has been fabricated by a wet impregnation method using waste nitrogen-containing mantis shrimp shell as a carbon precursor and KOH as an impregnation solution. The synthesized NPLC-2 shows a large surface area of 1222.961 m2...
Context in source publication
Context 1
... which leads to the high specic capacitance. 27 Moreover, the small mesopores of about 3 nm can accelerate the electrolyte ion transfer and the large mesopores (>10 nm) could store electrolyte on standby for fast electrochemical reactions. 28 FTIR spectra were taken for the qualitative analysis of the chemical constitution of NPLCs, as shown in Fig. 4. The typical peak positioned at 3430 cm À1 is assigned to the O-H stretching vibration stemming from H 2 O and the three peaks at 2970 cm À1 , 2920 cm À1 and 2850 cm À1 relate to the stretching vibra- tion of the C-H bond. The sharp absorption peak observed at 1630 cm À1 is attributed to the stretching vibration of C]X (X ¼ C, N, or ...
Similar publications
Benzimidazole derivatives were synthesized, characterized, and tested as a corrosion inhibitor for J55 steel in a 3.5 wt % NaCl solution saturated with carbon dioxide. The experimental results revealed that inhibitors are effective for steel protection, with an inhibition efficiency of 94% in the presence of 400 mg/L of inhibitor. The adsorption of...
Citations
... The bands around 1560 and 1060 cm −1 observed spectrum indicate the presence of a C=C (from the aromatic ring) and C-O-C stretching, respectively [49,50]. The minor peak at 668 cm −1 corresponds to N-H out-of-plane deformation vibration [51]. The strong absorption band at around 470 cm −1 is assigned to the C-S (sulfur bonded with carbon matrix)/S-O (oxidized sulfur)/-CH 3 out-plane stretching on aromatic carbon functional groups. ...
The growing energy demand and environmental issues have encouraged the development of novel and sustainable energy. Hydrogen is one of the cleanest and most sustainable energy sources that provides an environmentally friendly alternative future fuel. The recent development in hydrogen production through electrocatalytic water-splitting is somewhat high-performance. The potential electrocatalysts play an essential role in hydrogen evolution reactions (HER) for electrochemical water splitting, where expensive and low-abundance platinum-based materials are the standard catalysts for HER. Herein, metal-free, low-cost, and naturally abundant chebulic myrobalan was employed as a source for the preparation of porous carbon by direct pyrolysis route, and the resulting porous carbon was utilized as an electrocatalyst for the production of hydrogen gas. The various analytical techniques confirmed the existence of sulfur, nitrogen, and oxygen in the prepared chebulic myrobalan-derived porous carbon (CM-PC). The presence of effective heteroatoms in the CM-PC may lead to interactive effects between the heteroatoms and porous carbon structures; this suggests the enhancement of the electrochemical performance of HER. The surface area of CM-PC was obtained as 675 m2 g−1 by BET measurement. The CM-PC exhibited a moderate degree of graphitization with hydrophilic functionalities. Based on these excellent properties, the CM-PC was used as an electroactive material to fabricate the working electrode and as a metal-free electrocatalyst for HER in a 0.5 M H2SO4 aqueous solution. The resulting CM-PC delivered a superior catalytic activity toward HER with a Tafel slope of ~ 79 mV decade–1 (Overpotential − 166 mVRHE at a current density of − 10 mA cm–2) and excellent long-term stability in an acidic medium. Importantly, these findings prove that the chebulic myrobalan (biomass) was turned into an effective electrocatalyst for hydrogen generation in the economical route, thereby challenging the uniqueness of platinum catalysts in the hydrogen economy. The result indicates that as-prepared catalysts (CM-PC) have excellent application value in energy and environment.
... These C=O vibration bands could be further attributed to carboxylic groups; however, the carbonyl and lactone groups are mostly responsible because they are stable at lower temperatures and the material was prepared at 700 °C [35]. In addition to the mentioned vibrations, this peak is also attributed to the stretching C=N vibrations, and the distinct peak at 1385 cm −1 could be identified as C-N vibration modes [36]. This indicates that nitrogen functional groups are also present in the carbon structure in addition to the oxygen functionalities. ...
... The broad band in the region between 1200 and 970 cm −1 can be the consequence of two overlapping bands: C-O and C-N banding vibration peaks. The C-O stretching vibration peak (from COOH) typically appears between 1120 cm −1 and 1160 cm −1 [37,38], while the C-N band is usually centered around 1040 cm −1 [36]. To further investigate material surface chemistry, FTIR analysis was performed ( Figure 3). ...
... These C=O vibration bands could be further attributed to carboxylic groups; however, the carbonyl and lactone groups are mostly responsible because they are stable at lower temperatures and the material was prepared at 700 • C [35]. In addition to the mentioned vibrations, this peak is also attributed to the stretching C=N vibrations, and the distinct peak at 1385 cm −1 could be identified as C-N vibration modes [36]. This indicates that nitrogen functional groups are also present in the carbon structure in addition to the oxygen functionalities. ...
The development of carbon materials with desirable textures and new aqueous electrolytes is the key strategy to improve the performance of supercapacitors. Herein, a deep eutectic solvent (DES) was used for in situ templating of a carbon material. A carbon material was characterized (XRD, N2- physisorption, FTIR, SEM and EDS) and used as an electrode material for the first time in multivalent-based supercapacitors. In situ templating of carbon was performed using a novel DES, which serves as a precursor for carbon and for in situ generation of MgO. The generation of MgO and its roles in templating of carbon were discussed. Templating of carbon with MgO lead to an increase in surface area and a microporous texture. The obtained carbon was tested in multivalent-ion (Al3+ and Mg2+) electrolytes and compared with H2SO4. The charge-storage mechanism was investigated and elaborated. The highest specific capacitance was obtained for the Al(NO3)3 electrolyte, while the operating voltage follows the order: Mg(NO3)2 > Al(NO3)3 > H2SO4. Electrical double-layer capacitance (versus pseudocapacitance) was dominant in all investigated electrolytes. The larger operating voltage in multivalent electrolytes is a consequence of the lower fraction of free water, which suppresses hydrogen evolution (when compared with H2SO4). The GCD was experimentally performed on the Al(NO3)3 electrolyte, which showed good cyclic stability, with an energy density of 22.3 Wh kg−1 at 65 W kg−1.
... Biomass in electrocatalysis is often used as a precursor for the formation of conductive carbon supports with high surface areas and ORR activities in alkaline conditions. 203 Bioderived catalysts have been successfully prepared from numerous materials, including wood, 56−59 sisal leaves, 205 pine needles, 206 rice husks, 207 bamboo, 208 loofahs, 209 watermelon, 210 pomelo peels, 211 hemp, 212,213 clover, 214 peanut skin, 215 fern fiber, 216 bones, 60−63205 leather, 217 shrimp shells, 218 and even butterfly wings. 219 Clearly some of these sources are not practically suitable due to limited supplies (an example is discussed further in section 3.2) and environment destruction. ...
The development of efficient and sustainable electrochemical systems able to provide clean-energy fuels and chemicals is one of the main current challenges of materials science and engineering. Over the last decades, significant advances have been made in the development of robust electrocatalysts for different reactions, with fundamental insights from both computational and experimental work. Some of the most promising systems in the literature are based on expensive and scarce platinum-group metals; however, natural enzymes show the highest per-site catalytic activities, while their active sites are based exclusively on earth-abundant metals. Additionally, natural biomass provides a valuable feedstock for producing advanced carbonaceous materials with porous hierarchical structures. Utilizing resources and design inspiration from nature can help create more sustainable and cost-effective strategies for manufacturing cost-effective, sustainable, and robust electrochemical materials and devices. This review spans from materials to device engineering; we initially discuss the design of carbon-based materials with bioinspired features (such as enzyme active sites), the utilization of biomass resources to construct tailored carbon materials, and their activity in aqueous electrocatalysis for water splitting, oxygen reduction, and CO2 reduction. We then delve in the applicability of bioinspired features in electrochemical devices, such as the engineering of bioinspired mass transport and electrode interfaces. Finally, we address remaining challenges, such as the stability of bioinspired active sites or the activity of metal-free carbon materials, and discuss new potential research directions that can open the gates to the implementation of bioinspired sustainable materials in electrochemical devices.
... Interestingly, no appreciable bands were obtained in this range, except in the case of ACP and ACPE, where a minor band in the vicinity of 3451 cm -1 was evolved which could be attributed to O-H vibrations of hydroxyl species or adsorbed water [61]. Next, the three peaks in the proximity of 3016 cm -1 , 2970 cm -1 , and 2935 cm -1 indicates the presence of C-H bonds [62]. Peaks approximately at 2355 cm -1 and 2326 cm -1 (marked with *) emerged due to adsorption of carbon dioxide into the sample from the surrounding environment [1,7]. ...
Mass generation of scrap tires presents a major challenge for environmental safety, however, their upcycling into carbon-based nanomaterials by the virtue of pyrolysis treatments can open up new windows for energy conversion and storage technologies in the context of the circular economy. Herein, we report the synthesis of Fe-N-C oxygen reduction reaction (ORR) electrocatalyst for fuel cell (FC) applications using carbonaceous char derived from scrap tires through microwave-assisted pyrolysis (MAP). The char obtained from MAP was activated with potassium hydroxide and then pyrolyzed at a high temperature to fabricate Fe-N-C after mixing with iron and nitrogen precursors. Finally, the developed Fe-N-C was ball-milled and acid-etched for homogenization and leaching of iron oxide nanoparticles. In this study, structural evaluation during each synthesis step was elucidated and correlated with the ORR activity in all three pHs i.e. acidic, neutral, and alkaline. Moreover, the effect of electrocatalyst loading on ORR kinetics was also analyzed using two different loadings (0.2 and 0.6 mg cm⁻²) on the rotating ring disk electrode (RRDE). The developed Fe-N-C demonstrated encouraging onset potentials of 0.881, 0.822, and 0.936 V vs RHE in acidic, neutral, and alkaline conditions, respectively. Whereas the ORR activity was slightly reduced after the milling-etching step. Lower peroxide yield together with a tetra-electronic reduction of oxygen was witnessed in acidic and neutral conditions, however, peroxide production was increased in the alkaline medium.
... The typical peak position at 3351 cm −1 was assigned to the O−H stretching vibration, and the two distinct peaks at 2923 and 2852 cm −1 were assigned to the asymmetric and symmetric stretching of the C−H bond. 49 The doublet observed between 1650 and 1750 cm −1 has been resolved and assigned to two peaks, i.e., CO (1719 cm −1 ) and aromatic CC (1670 cm −1 ). The deconvoluted peaks are given in Figure S4b. ...
... 50 The sharp absorption peaks, centered at 748 and 692 cm −1 were ascribed to the outof-plane deformation vibration of the N−H bonds. 49 Similar FTIR results were reported by Tao et al., 23 but the study was The XPS survey scans given in Figure 5a−c clearly exhibit the presence of C, O, and N, verifying the presence of N-GO at all plasma powers. The peaks at 285.6, 400.8, and 532.8 eV were assigned to the C 1s core level spectrum of sp 2 -C, the N 1s spectrum of the doped N, and the O 1s spectrum, respectively. ...
... The doping percentage of 3.55% N atoms achieved through this facile method was comparable to those reports where doping was introduced via multistep processes. 45,49,51 For instance, in the modified Hummers method, 47 5.6% of nitrogen content was obtained. ...
... [19] The peak at 1380cm À1 is identified as the CÀNv ibrationm odes. [20] The peak at 1210 cm À1 correspondst ot he characteristic stretching vibrations of CÀNb onds. The peak at 1040 cm À1 is due to the S=Os tretching vibration. ...
... eV being attributed to pyridinic, pyrrolic, and quaternary Na toms,r espectively. [20,26] The S2ps pectrum in Figures 5d(i-iii)a nd S4 a(iv) can be fitted with two peaks. The binding energies of the S2ps pectrumF igure 5d and Figure S4 a(iv) have fitted two differentp eaks. ...
Carbon‐based symmetric supercapacitors (SCs) are known for their high power density and long cyclability, making them an ideal candidate for power sources in new‐generation electronic devices. To boost their electrochemical performances, deriving activated carbon doped with heteroatoms such as N, O, and S are highly desirable for increasing the specific capacitance. In this regard, activated carbon (AC) self‐doped with heteroatoms is directly derived from bio‐waste (lima‐bean shell) using different KOH activation processes. The heteroatom‐enriched AC synthesized using a pretreated carbon‐to‐KOH ratio of 1:2 (ONS@AC‐2) shows excellent surface morphology with a large surface area of 1508 m² g⁻¹. As an SC electrode material, the presence of heteroatoms (N and S) reduces the interfacial charge‐transfer resistance and increases the ion‐accessible surface area, which inherently provides additional pseudocapacitance. The ONS@AC‐2 electrode attains a maximum specific capacitance (Csp) of 342 F g⁻¹ at a specific current of 1 Ag⁻¹ in 1 m NaClO4 electrolyte at the wide potential window of 1.8 V. Moreover, as symmetric SCs the ONS@AC‐2 electrode delivers a maximum specific capacitance (Csc) of 191 F g⁻¹ with a maximum specific energy of 21.48 Wh kg⁻¹ and high specific power of 14 000 W kg⁻¹ and excellent retention of its initial capacitance (98 %) even after 10000 charge/discharge cycles. In addition, a flexible supercapacitor fabricated utilizing ONS@AC‐2 electrodes and a LiCl/polyvinyl alcohol (PVA)‐based polymer electrolyte shows a maximum Csc of 119 F g⁻¹ with considerable specific energy and power.
... All three samples show two peaks at about 24°and 44°, which are corresponding to the (002) diffraction and the (100) diffraction, respectively [44,45]. The two broad and weak peaks of NHPCA show the high degree of disorder which provides larger ions transport channel compared to the graphitized structure [46]. This can also be proved by the highly disordered lattice in HRTEM image (Fig. 1i). ...
In this work, nitrogen-doped carbon with hierarchical porous and hollow sphere structure has been synthesized through a simple and facile route of spray drying using glycine as the nitrogen-containing carbon source. After KOH activation, the prepared material (NHPCA) shows a large specific surface area of 962 m² g⁻¹ with moderate N-doping of 5.74% and exhibits a high specific capacitance of 271 F g⁻¹ in 6 M KOH electrolyte at 1.0 A g⁻¹, remarkable rate capability and particularly stable cycling performance with no significant specific capacitance drop after 10000 cycles at 1.0 A g⁻¹. The excellent electrochemical properties come from the unique structure and the doping of nitrogen. The hierarchical pore structure improves the efficiency of electrolyte ions transport, and diffusion and the hollow sphere structure further facilitates mass transport. The doping of nitrogen increases the total capacitance by providing redox pseudo-capacitance. The results indicate the as-prepared nitrogen-doped carbon with hierarchical porous and hollow sphere structure can be used as a hopeful candidate for an efficient electrode of commercial supercapacitors devices.
It is necessary to separate CO2 from biogas to improve its quality for the production of biomethane. Herein, an improvement in the separation of CO2/CH4via adsorption was achieved by modifying the surface of CMS. The surface modification of CMS was performed by impregnation with metal oxide (Fe3O4) and N-doping (DES-[ChCl:Gly]). Subsequently, the efficacy of the surface-modified CMS was investigated. This involved CMS modification, material characterization, and performance analysis. The uptake of CO2 by CMS-DES-[ChCl:Gly] and CMS-Fe3O4 was comparable; however, their performance for the separation of CO2/CH4 was different. Consequently, CMS-DES-[ChCl:Gly] and CMS-Fe3O4 exhibited ca. 1.6 times enhanced CO2 uptake capacity and ca. 1.70 times and 1.55 times enhanced CO2/CH4 separation, respectively. Also, both materials exhibited similar repeatability. However, CMS-DES-[ChCl:Gly] was more difficult to regenerate than CMS-Fe3O4, which is due to the higher adsorption heat value of the former (59.5 kJ).
Currently, wastewater treatment is a vital environmental concern as it is a huge challenge for people to live healthy life. Consequently, legislation aimed at ensuring the removal of toxic effluents...
Practical utilization of Li-sulfur batteries (LSBs) is still hindered by the sulfur cathode side due to its inferior electrical conductivity, huge volume expansion and adverse polysulfide shuttling effects. Though using polar catalysts coupled with mesoporous carbons may well surmount these barriers, such unsheltered catalysts rarely survive due to oversaturated polysulfide adsorption and extra sulfuration side reactions. To overcome above constrains, we herein propose to implant highly reactive nanocatalysts into carbon matrix with few nanometers insertion depth for mechanical protection. As a paradigm study, we have embedded La2O3-quantum dots (QDs) into carbon nanorods, which are then assembled into carbon microspheres (CMs). As evaluated, La2O3 QDs-CMs can help elevate the cathode redox reaction kinetics and sulfur utilization ratios, delivering a large capacity of 1392 mAh g-1 at 0.25C and high-capacity retention of 76% after total cycling. The thin carbon layers on La2O3 QDs exert a key role in impeding excess polysulfide accumulation on catalysts and thus prevent their deactivation/failure. Our strategy may guide a smart way to make catalysts-involved sulfur cathode systems with ultra-long working durability for LSBs applications.
