Simple Electrophoretic Technique Research Articles

Electrophoretic Deposition of Polyethylene Oxide-Based Gel-Polymer Electrolyte for 3D Lithium-Ion Batteries

Despite the advances made in lithium-ion batteries (LIBs) over the last few decades, improved energy and power density is still required for portable devices, transit, and stationary applications [1-3]. Along with developing new materials, optimizing the shape of the battery electrodes is critical for improving the battery performance since the structure of these electrodes has a large impact on ion movement and reaction kinetics. The appeal of 3D structured batteries comes from certain operating features that are not available with conventional 2D geometries. One important feature is the ability to increase areal capacity (mAh cm−2) within a given footprint area of the electrode .Up to today, various methods were employed to coat the foam-type 3D electrodes with polymer or solid-state electrolytes: spin coating, layer-by-layer, and drop coating. Nonetheless, only a number of full-cell operation cases were disclosed, which led to the conclusion that, despite many attempts, drawbacks still exist in solving the homogeneous coating problem of polymer electrolytes.In this work, we report on the simple and facile coating process of polymer electrolyte on the intricate 3D structured NiO@Ni foam anode with the electrophoretic technique. To the best of our knowledge, it was not yet reported in the literature. The conformally coated polymer layer is proven to be very thin and homogeneous without any defects. The NiO@Ni foam/PEO configuration without the use of a commercial separator displayed stable cyclability up to 100 cycles with capacity retention of 88% and coulombic efficiency of 99%. The results are very promising for solving the problem of integrating polymer electrolytes onto any 3D structured anodes.In summary, a facile and simple electrophoretic technique was employed to conformally coat PEO gel-polymer electrolyte onto foam-type NiO/Ni anode for LIBs for the first time. Two electrodes of NiO/Ni foam as a working electrode and Pt metal as a counter electrode were used for the EPD process. Where the PEO solution acted as an electrolyte and, in the end, formed on the NiO/Ni foam surface. Through investigating various layers of PEO, it was concluded that the method allowed obtaining homogeneous thin films of around 2.66 μm for optimal 10 layers, which were free of cracks and defects. The electrochemical performance of the gel-polymer electrolyte PEO with commercially available liquid electrolyte 1M LiPF6 electrolyte solution in EC/EMC/DC was comparable to the traditional separator when used without it in a half-cell with lithium. The cycling stability results displayed an outstanding performance for the PEO electrolyte, delivering a capacity of 406 mAh g-1 at a 0.1 C rate after the 100th cycle. The stability of the formed PEO on the surface of the anode was demonstrated by FTIR analysis after 100 cycles. The stated simple approach allowed a cell operation at room temperature without a commercial separator, which is an excellent result for further developing high-energy-density full 3D batteries.

Tailoring oxygen evolution performances of carbon nitride systems fabricated by electrophoresis through Ag and Au plasma functionalization

The strategic interest in the production of green hydrogen by sunlight-activated water splitting has stimulated significant efforts aimed at the implementation of active and cost-effective catalysts for the oxygen evolution reaction (OER), the overall process bottleneck. Herein, we report on an original fabrication route to OER electrocatalysts based on graphitic carbon nitride. In particular, the target systems were deposited on conductive glass substrates via a simple electrophoretic technique and functionalized with highly dispersed noble metals (Au, Ag or Au + Ag) in low amounts by radio frequency (RF)-sputtering under mild conditions. An advanced material characterization revealed the possibility of tailoring carbon nitride morphology as a function of the used precursor and of achieving a homogeneous spatial distribution of the functionalizing metals. The latter ranged from atomically dispersed (silver), to low-sized nanoaggregates (gold) or partially alloyed core–shell nanoparticles (gold+silver), with an intimate metal-nitride interfacial contact. Functional tests evidenced a remarkable sensitivity to Vis light even at low applied potentials, and photoelectrocatalytic performances directly dependent on the nature of metal species and on the features of the underlying carbon nitride deposit. These evidences, rationalized mainly on the basis of Schottky junctions and the possible concurrence of surface plasmon resonance (SPR), candidate the proposed strategy as a versatile route to cheap and efficient OER electrocatalysts for energy conversion.

Vertically Aligned MoS2 Quantum Dots/Nanoflakes Heterostructure: Facile Deposition with Excellent Performance toward Hydrogen Evolution Reaction

A facile, low-cost, and straightforward procedure was developed for vertical deposition of MoS2 quantum dots (QDs)/nanoflakes (NFs) on fluorine-doped tin oxide (FTO) substrate without any binder. Bulk MoS2 powder was exfoliated in a bath sonicator followed by tip sonicator inside a water–ethanol (0.5/0.5 volume ratio) solution. The obtained MoS2 QDs/NFs are deposited on FTO substrate via a simple electrophoretic technique which resulted in vertical deposition of MoS2 nanoflakes. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) confirmed the formation of MoS2 nanoflakes with thickness of ∼20 nm and lateral dimension of ∼400 nm; transmission electron microscopy (TEM) and AFM analysis revealed that many single- or two-layer MoS2 quantum dots exist with lateral size of ∼5 nm on average on the basal plains of MoS2 nanoflakes. Electrochemical measurements indicated that the vertical MoS2 QDs/NFs/FTO electrode has a Tafel slope of 74 mV/decade and charge transport resistance ...

Use of enzyme electrophoresis for differentiating Schistosoma nasale and S. spindale infections of Indoplanorbis exustus in Sri Lanka

Indoplanorbis exustus is the intermediate snail host of both Schistosoma nasale and S. spindale in Sri Lanka. Due to the similar morphology of the cercariae difficulties exist in identifying the species of schistosome infecting snails at transmission sites. Isoelectric focusing in polyacrylamide gels of malate dehydrogenase, glucose phosphate isomerase, phosphoglucomutase and acid phosphatase has been carried out on extracts of cercariae and potentially useful diagnostic markers have been identified. Cellulose acetate membrane electrophoresis has been used to separate two glucose phosphate isomerase phenotypes each of which appears to be diagnostic for one of the species. This simple electrophoretic technique has been used to identify schistosome infections in Indoplanorbis exustus collected at two transmission sites in Sri Lanka. Out of a total of 1,240 snails collected, 13 snails were shown to be infected with S. nasale, 19 with S. spindale and two snails were found to have mixed infections.

Rubisco as a taxonomic tool: Introducing a simple electrophoretic technique for separating the holoenzyme

A simple electrophoretic technique for separating Rubiscoholoenzyme (ribulose bisphosphate carboxylase-oxygenase) from crude extracts is introduced. No preliminary purification steps are required. To prove the validity of the technique we rely on well studiedBrassica spp., tobacco and spinach. We recommend this method for studies concerned with intrageneric relationships and for proving the intraspecific constancy of Rubisco.

Circular Herpesvirus sylvilagus DNA in spleen cells of experimentally infected cottontail rabbits.

Cottontail rabbits (Sylvilagus floridanus) were infected with Herpesvirus sylvilagus, and spleen cells were analyzed for the presence of virus-specific, covalently closed circular, and linear DNA molecules by a simple electrophoretic technique, followed by transfer to nitrocellulose filters and hybridization with cloned viral DNA (Gardella et al., J. Virol. 50:248-254, 1984). Approximately 0.2 copies per cell of circular DNA and 0.2 copies per cell of linear DNA were detected by hybridization with a cloned viral DNA fragment. The size of the viral DNA was estimated at ca. 158 kilobase pairs. Restriction endonuclease patterns suggested structural similarities to cottontail herpesvirus DNA.

Simple electrophoretic technique for creatine kinase MM isozyme in neonatal duchenne muscular disease screening using dried blood samples

By increasing diadenosine pentaphosphate to a final concentration of 75 μmol to 100 μmol/l to inhibit excess adenylate kinase, a highly sensitive substrate in a gelatin matrix allowed the development of a simple and cheap electrophoretic technique for creatine kinase MM isozyme in dried blood samples. The method is suitable for neonatal Duchenne muscular dystrophy screening, and it is an alternative method for a previously described bio-luminescent assay, which requires special equipment.

A simple electrophoretic technique for the estimation of complement C3 conversion: Specific application to the investigation of anaphylactoid response to I.V. agents

A simple electrophoretic technique employing commercially available agarose films is described for the routine estimation of plasma complement C3 conversion. This technique has particular value in the investigation of anaphylactoid responses in patients following the administration of intravenous hypnotic drugs, plasma substitutes or radio-contrast media.

THE VALUE OF LDH ISOENZYMES IN THE RAPID DIAGNOSIS OF BRAIN TUMOURS

The value of LDH isoenzymes in the rapid diagnosis of brain tumoursA combined biochemical and histopathological analysis of 126 intracranial tumour biopsies has been undertaken to assess the possible value of LDH isoenzyme analyses in differential diagnosis. LDH isoenzymes were separated by a simple electrophoretic technique and visualized by a histochemical staining method. The analytical results were quantitated in the densitometer. Using this technique it is possible to obtain results within 15 min of reception of the biopsy specimen and only small pieces of tumour material are required. The results of the investigation have shown that all the tumours investigated have an LDH isoenzyme pattern which is different from that of normal brain. Although in some cases the abnormal pattern was non‐specific it was found that certain general rules could be formulated, and the technique is a useful supplement to histological evaluation of frozen sections.

Electrophoretic examination of human serum amylase isozymes by using a simple thin layer polyacrylamide gel electrophoresis

A simple electrophoretic technique using thin layer polyacrylamide gel provided a good resolution of serum amylase isozymes with separation of up to 9 isozyme fractions. A strong oxidizing agent, ammonium persulfate, which had been used in polyacrylamide gel formation system, was removed by prior electrophoresis from the separating gel before sample application to avoid possible degradation of amylase molecule into subunits.From the results of electrophoretic mobility studies of serum, pancreatic and salivary amylase isozymes, it was concluded that amylase isozymes in human serum were of pancreatic and salivary origin.In patients with acute pancreatitis, increased amylase activities were observed on those of pancreatic origin. On the contrary, in patients with pancreatectomy, these isozyme activities disappeared from serum. In patients with mumps, amylase activities of salivary origin, which were observed in patients with pancreatectomy, increased in serum.