The design of advanced high-energy-density supercapacitors requires the design of unique materials that combine hierarchical nanoporous structures with high surface area to facilitate ion transport and excellent electrolyte permeability. Here, shape-controlled 2D nanoporous carbon sheets (NPSs) with graphitic wall structure through the pyrolysis of metal-organic frameworks (MOFs) are developed. As a proof-of-concept application, the obtained NPSs are used as the electrode material for a supercapacitor. The carbon-sheet-based symmetric cell shows an ultrahigh Brunauer-Emmett-Teller (BET)-area-normalized capacitance of 21.4 µF cm (233 F g ), exceeding other carbon-based supercapacitors. The addition of potassium iodide as redox-active species in a sulfuric acid (supporting electrolyte) leads to the ground-breaking enhancement in the energy density up to 90 Wh kg , which is higher than commercial aqueous rechargeable batteries, maintaining its superior power density. Thus, the new material provides a double profits strategy such as battery-level energy and capacitor-level power density.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/adma.201705789 | DOI Listing |
ACS Nano
January 2025
College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, P. R. China.
Electrocatalytic CO-to-CO conversion with a high CO Faradaic efficiency (FE) at low overpotentials and industrial-level current densities is highly desirable but a huge challenge over non-noble metal catalysts. Herein, graphitic N-rich porous carbons supporting atomically dispersed nickel (NiN-O sites with an axial oxygen) were synthesized (denoted as O-Ni-N-GC) and applied as the cathode catalyst in a CORR flow cell. O-Ni-N-GC showed excellent selectivity with a FE over 92% at low overpotentials ranging from 17 to 60 mV, and over 99% at 80 mV.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Department of Physics, Malaviya National Institute of Technology Jaipur, Rajasthan 302017 India. Electronic address:
Designing advanced materials that effectively mitigate the poor cycle life of battery-type electrodes with high specific capacities is crucial for next-generation energy storage systems. Herein, graphene oxide-ceria (GO-CeO) nanocomposite synthesized via a facile wet chemical route is explored as cathode for high-performance supercapacitors. The morphological analysis suggests fine ceria (CeO) nanoparticles dispersed over ultrathin graphene oxide (GO) sheets while structural studies reveal face-centered cubic phase of CeO in the nanocomposite.
View Article and Find Full Text PDFBiotechnol Prog
January 2025
AdBIOPRO, VINNOVA Competence Centre for Advanced Bioproduction by Continuous Processing, Royal Institute of Technology (KTH), Stockholm, Sweden.
The possibility to produce recombinant adeno-associated virus (rAAV) by adherent HEK293T cells was studied in a stirred tank bioreactor (STR) culture of cell aggregates. A proof-of-concept of rAAV production was successfully demonstrated in a process where single cells were first expanded, then cell aggregates were formed by dilution into a different medium 1 day before triple plasmid transfection was conducted. An alternative approach for the STR inoculation using a seed taken from a high cell density perfusion (HCDP) culture was also investigated.
View Article and Find Full Text PDFSmall
January 2025
Center of Nanomaterials for Renewable Energy (CNRE), State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, P. R. China.
The traditional perfluorosulfonic acid proton exchange membrane is crucial for proton exchange membrane fuel cells, but its high cost has impeded broader commercialization. In this study, a novel concept of a cost-effective and stable vertically aligned polydopamine-intercalated montmorillonite membrane (VAPMM) is introduced. 2D nanochannels formed within the lamellar structure of polydopamine-coated montmorillonite nanosheets provide a significant stable in-plane proton conductivity of 0.
View Article and Find Full Text PDFAdv Mater
January 2025
Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK.
Thick metamorphic buffers are considered indispensable for III-V semiconductor heteroepitaxy on large lattice and thermal-expansion mismatched silicon substrates. However, III-nitride buffers in conventional GaN-on-Si high electron mobility transistors (HEMT) impose a substantial thermal resistance, deteriorating device efficiency and lifetime by throttling heat extraction. To circumvent this, a systematic methodology for the direct growth of GaN after the AlN nucleation layer on six-inch silicon substrates is demonstrated using metal-organic vapor phase epitaxy (MOVPE).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!