Effect of interfacial state in bipolar membrane on rectification and water splitting

Irradiation‐induced grafting of polyacrylamide onto the sulphonated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (SPPO) films as well as its use as catalytical layer in a bipolar membrane

“…Compared with the bipolar membranes using un-grafted SPPO as cation-exchange layer, all the bipolar membranes prepared from the grafted SPPO possess lower voltage. These improvements in bipolar membrane's performance are no doubt to origin from the grafted polyacrylamide, which has two positive effects for water dissociation: one is that it has high water affinity and thus can provide more hydrophilic points for water dissociation as discussed intensively in literatures; 14,28,29 the other is that it is a weak base and can catalyze the water dissociation according to the following conventional proton transfer reaction:…”

Effect of ion-exchange nanofiber fabrics on water splitting in bipolar membrane

“…All measurements were carried out at 23 ± 0.5 • C. Under reverse bias conditions, current and voltage are said to be negative values, which appear in the third quadrant. However, in this work, the measured current and voltage were multiplied by −1 to place them in the first quadrant [2,3]. The pH change in each compartment was measured by a pH meter (TOA WM-60EG, Japan) equipped with pH electrodes (TOA GST-5721C, Japan).…”

“…BPM-based electrodialysis is an efficient process for generating acids and bases without by-products and is applicable to the recovery of acid and base from wastewater or the production of organic and inorganic acids [1][2][3][4][5]. The watersplitting phenomenon occurs at the interface between the CEL and AEL.…”

“…Therefore, the water-splitting capability of BPMs depends on their interfacial state. It is well accepted that materials immobilized in the intermediate region, such as weak acids (e.g., carboxylic and phosphoric groups), bases (e.g., tertiary and quaternary amino groups), and metallic compounds (e.g., Cr 3+ , Fe 3+ ), catalyze the water-splitting reaction [1,2] [2]. In addition, Chou and Tanioka suggested composite bipolar membranes (CBM) consisting of a three-layered structure (Fig.…”

Fundamental studies on the intermediate layer of a bipolar membrane

“…In order to further discover the relation between the water-splitting effect and the chemical composition of the middle layer, Tanioka and co-workers investigated the performance of bipolar membranes with an anionexchange polymer inserted, or a middle layer formed from polystyrene, polycarbonate, or a mixture of N -succinyl chitosan and polyvinyl alcohol [14][15][16]. However, our recent study shows that polyethylene glycol is a good catalyst for water dissociation in a bipolar membrane, indicating that the wetness of the junction is also crucial [17].…”