scholarly journals Hierarchical Micro/Mesoporous Carbons Synthesized with a ZnO Template and Petroleum Pitch via a Solvent-Free Process for a High-Performance Supercapacitor

ACS Omega ◽  
2017 ◽  
Vol 2 (5) ◽  
pp. 2106-2113 ◽  
Author(s):  
Guan-Wen Liu ◽  
Tsung-Yi Chen ◽  
Cheng-Han Chung ◽  
Hong-Ping Lin ◽  
Chun-Han Hsu
2021 ◽  
Vol 5 (7) ◽  
pp. 188
Author(s):  
Chen Fang ◽  
Haiqing Xiao ◽  
Tianyue Zheng ◽  
Hua Bai ◽  
Gao Liu

Cycling stability is a key challenge for application of silicon (Si)-based composite anodes as the severe volume fluctuation of Si readily leads to fast capacity fading. The binder is a crucial component of the composite electrodes. Although only occupying a small amount of the total composite mass, the binder has major impact on the long-term electrochemical performance of Si-based anodes. In recent years, water-based binders including styrene-butadiene rubber (SBR) and carboxymethyl cellulose (CMC) have attracted wide research interest as eco-friendly and low-cost alternatives for the conventional poly(vinylidene difluoride) (PVDF) binder in Si anodes. In this study, Si-based composite anodes are fabricated by simple solid mixing of the active materials with subsequent addition of SBR and CMC binders. This approach bypasses the use of toxic and expansive organic solvents. The factors of binder, silicon, and graphite materials have been systematically investigated. It is found that the retained capacities of the anodes are more than 440 mAh/g after 400 cycles. These results indicate that organic solvent free process is a facile strategy for producing high performance silicon/graphite composite anodes.


RSC Advances ◽  
2021 ◽  
Vol 11 (15) ◽  
pp. 8628-8635
Author(s):  
Chang Ki Kim ◽  
Jung-Min Ji ◽  
M. Aftabuzzaman ◽  
Hwan Kyu Kim

The incorporation of the Te element into nitrogen-doped carbon-based nanomaterials is a good strategy to improve the capacitive performance of carbon materials and the incorporation of two types of atoms improves the overall capacitive performance of the materials due to a synergetic effect.


Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 164
Author(s):  
Patrícia M. Carvalho ◽  
Rita C. Guedes ◽  
Maria R. Bronze ◽  
Célia M. C. Faustino ◽  
Maria H. L. Ribeiro

Lipoaminoacids (LAA) are an important group of biosurfactants, formed by a polar hydrophilic part (amino acid) and a hydrophobic tail (lipid). The gemini LAA structures allow the formation of a supramolecular complex with bioactive molecules, like DNA, which provides them with good transfection efficiency. Since lipases are naturally involved in lipid and protein metabolism, they are an alternative to the chemical production of LAA, offering an eco-friendly biosynthetic process option. This work aimed to design the production of novel cystine derived gemini through a bioconversion system using immobilized lipases. Three lipases were used: porcine pancreatic lipase (PPL); lipase from Thermomyces lanuginosus (TLL); and lipase from Rizhomucor miehei (RML). PPL was immobilized in sol-gel lenses. L-cystine dihydrochloride and dodecylamine were used as substrates for the bioreaction. The production of LAA was evaluated by thin layer chromatography (TLC), and colorimetric reaction with eosin. The identification and quantification was carried out by High Performance Liquid Chromatographer-Mass Spectrometry (HPLC-MS/MS). The optimization of media design included co-solvent (methanol, dimethylsulfoxide), biphasic (n-hexane and 2-propanol) or solvent-free media, in order to improve the biocatalytic reaction rates and yields. Moreover, a new medium was tested where dodecylamine was melted and added to the cystine and to the biocatalyst, building a system of mainly undissolved substrates, leading to 5 mg/mL of LAA. Most of the volume turned into foam, which indicated the production of the biosurfactant. For the first time, the gemini derived cystine lipoaminoacid was produced, identified, and quantified in both co-solvent and solvent-free media, with the lipases PPL, RML, and TLL.


RSC Advances ◽  
2016 ◽  
Vol 6 (60) ◽  
pp. 55382-55392 ◽  
Author(s):  
Jie Xu ◽  
Jie-Kun Shang ◽  
Quan Jiang ◽  
Yue Wang ◽  
Yong-Xin Li

g-C3N4 materials have been prepared at lower temperatures (450–475 °C) by the aid of alkali treatment. In cycloaddition of CO2 to epoxides, the g-C3N4 materials demonstrated high and stable catalytic activities.


2017 ◽  
Vol 41 (21) ◽  
pp. 12901-12909 ◽  
Author(s):  
Chunfeng Shao ◽  
Ziqiang Wang ◽  
Errui Wang ◽  
Shujun Qiu ◽  
Hailiang Chu ◽  
...  

Guanine was, for the first time, used as a nitrogen source during the synthesis of nitrogen-doped porous carbons (NMCs) with enhanced electrochemical performance.


Sign in / Sign up

Export Citation Format

Share Document