Abstract
Polymer electrolyte membrane that has high proton conductivity and low methanol permeability are necessary for direct methanol fuel cells (DMFCs). A sodium alginate (SA)/polyvinyl alcohol ...(PVA)/montmorillonite (MMT)/graphene oxide (GO) quaternary composite membrane was effectively developed in this study. The homogeneous distribution of MMT and GO nanosheets in the SA/PVA/MMT/GO composite membrane was exhibited by scanning electron microscopy (SEM). Intriguingly, it has been established that the SA/PVA membrane contains chemical crosslinks between MMT and GO, which significantly contribute to the rise in proton conductivity. The SA/PVA/MMT/GO hybrid membrane has minimum loss modulus of 47.91% and storage modulus of up to 2.689 × 10
9
Pa, which are 3.8 times greater than those of SA/PVA‐MMT membrane without GO. This value indicates the viscosity and elasticity of the produced membrane. The quaternary composite membrane also exhibits outstanding oxidative stability and methanol barrier characteristics. The methanol permeability of SA/PVA/MMT/GO films 0.524 × 10
−9
cm
2
s
−1
, with methanol absorption as low as 9.72%. The best membrane performs at a high‐power density (1.761 mW/cm
2
) of DMFC at a GO content of 1.3 wt% because it obtains the maximum selectivity value (7.0529 × 10
6
S scm
−3
). Future commercial membranes may be replaced by the innovative quaternary membrane created in this work, which has significant potential.
HIGHLIGHTS
1. One of the most prevalent disease in females worldwide is cervical cancer.2. Simple and safe modality with high efficacy to treat cervical precancerous lesions before being progressed ...to cancer is necessary. 3. Trichloroacetic acid (TCA) has those advantages, so it will become an effective treatment for cervical precancerous lesions in the future.
ABSTRACT
Cervical cancer becomes one of the most prevalent disease in female worldwide. Human papillomavirus (HPV) is main etiology of cervical cancer, thus this disease is preventable. Before progressed into invasive cervical cancer, cervical precancerous lesions developed and classified into 3 stages: CIN1 (LSIL), CIN2, and CIN3 (CIN2+ also referred as HSIL). World Health Organization (WHO) arranged ‘screen-and-treat’ programme to treat cervical precancerous lesions immediately before it progressed to cancer. However, a simple and safe modality with high efficacy is necessary to accommodate this strategy. Trichloroacetic acid (TCA) has those advantages and some research suggested high efficacy to treat cervical precancerous lesions with simple, safe, and cost-effective. TCA has potential to become effective treatment for cervical precancerous lesions in the future.
Nafion is a commercial membrane that is widely used in direct methanol fuel cells (DMFC) but has critical constraints such as being expensive and having high methanol crossover. Efforts to find ...alternative membranes are actively being carried out, including in this study, which looks at producing a Sodium Alginate/Poly (Vinyl Alcohol) (SA/PVA) blended membrane with modification by montmorillonite (MMT) as an inorganic filler. The content of MMT in SA/PVA-based membranes varied in the range of 2.0-20 wt% according to the solvent casting method implemented. The presence of MMT was seen to be most optimal at a content of 10 wt%, achieving the highest proton conductivity and the lowest methanol uptake of 9.38 mScm
and 89.28% at ambient temperature, respectively. The good thermal stability, optimum water absorption, and low methanol uptake of the SA/PVA-MMT membrane were achieved with the presence of MMT due to the strong electrostatic attraction between H
, H
O
, and
OH ions of the sodium alginate and PVA polymer matrices. The homogeneous dispersion of MMT at 10 wt% and the hydrophilic properties possessed by MMT contribute to an efficient proton transport channel in SA/PVA-MMT membranes. The increase in MMT content makes the membrane more hydrophilic. This shows that the loading of 10 wt% MMT is very helpful from the point of view of sufficient water intake to activate proton transfer. Thus, the membrane produced in this study has great potential as an alternative membrane with a much cheaper cost and competent future performance.
This study reports the effect of plasticizers namely isopropanol, polyethylene glycol, maltitol and spermidine on the properties of the sodium alginate composite membrane. The concentration of each ...potential plasticizer was set at minimum to execute performance. Properties of sodium alginate were studied through characterization studies - Field Emission Scanning Electron Microscope (FESEM) to observe on the morphology structure. The membrane performance is also seen through water uptake and swelling ratio tests. Isopropanol produced better plasticizer with the lowest water uptake of 575.53% and less hydrophilic compared to spermidine (1268.46%), polyethylene glycol (1014.30%) and maltitol (595.82%). Further study may require copolymerization to support polyol for ensuring structure firmness. This study proven the plasticizers could enhance membrane’s flexibility in DMFC and becoming a promising choice of additives for better alginate-based membrane establishment.
Nafion, a widely utilized commercial membrane in direct methanol fuel cells (DMFC), presents significant limitations due to its cost and susceptibility to high methanol crossover. This study explores ...alternative membranes, focusing on Sodium Alginate/Poly (Vinyl Alcohol) (SA/PVA) blends with montmorillonite (MMT) modification as an inorganic filler. The MMT content in the SA/PVA membrane was varied from 2 to 20 wt% using the solvent casting method. Optimally, 10 wt% MMT content demonstrated the highest proton conductivity (9.38 mScm−1) and the lowest methanol uptake (89.28%) at ambient temperature. The SA/PVA-MMT membrane exhibited superior thermal stability, optimal water absorption, and reduced methanol uptake, attributed to the electrostatic attraction within the sodium alginate and PVA polymer matrices interacting with H+, H3O+, and –OH ions. The homogeneous dispersion of 10 wt% MMT, along with its hydrophilic properties, facilitated an efficient proton transport channel in SA/PVA-MMT membranes. Increasing MMT content enhanced membrane hydrophilicity, indicating that 10 wt% MMT loading is crucial for adequate water intake to activate proton transfer. This study suggests that the developed membrane holds great potential as a cost-effective alternative with competent performance for future applications.
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