Anhydrous proton-conducting imidazole triflate-SiO2 composite

Tu, Tran Anh; Phúc, Nguyễn Hữu

doi:10.1016/j.heliyon.2022.e12527

Cited by 1 publication

(2 citation statements)

References 35 publications

(34 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In recent years, there has been increasing interest in imidazole-based proton conductors. High-proton conductivity in imidazole or composite proton conductors based on imidazole has been reported. ,, Numerous studies have also been conducted on inorganic or organic-oriented framework-type proton conductors encapsulating imidazole as proton conduction species. – In addition, it was discovered that the silanol groups on the surface of SiO 2 could interact with imidazole through acid–base reactions, enhancing proton conductivity in the acid–base interaction region. – In this case, silanol group can act as a acid group due to the small p K a of around 4.4–4.5 . Our group has previously reported on the efficiency of SiO 2 -containing matrixes as proton conductors. – In this study, we developed novel proton conductors composed of both sides of imidazole sandwiched between HCl and SiO 2 as two types of materials through acid–base reactions using a mechanochemical milling technique (Figure a).…”

Section: Introductionmentioning

confidence: 99%

“…High-proton conductivity in imidazole or composite proton conductors based on imidazole has been reported. 10,12,13 Numerous studies have also been conducted on inorganic or organic-oriented framework-type proton conductors encapsulating imidazole as proton conduction species. 14−16 In addition, it was discovered that the silanol groups on the surface of SiO 2 could interact with imidazole through acid−base reactions, enhancing proton conductivity in the acid−base interaction region.…”

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and Structure-Electrochemical Property Relationships of Hybrid Imidazole-Based Proton Conductors for Medium-Temperature Anhydrous Fuel Cells

Maegawa,

Wlazło,

Huy Phuc

et al. 2023

Chem. Mater.

Self Cite

View full text Add to dashboard Cite

Medium-temperature anhydrous operation (above 120 °C) of polymer electrolyte membrane fuel cells (PEMFCs) has been extensively investigated, particularly for heavy-duty fuel cell applications. In this context, inorganic–organic composites based on acid–base reactions emerge as essential candidates for medium-temperature PEMFC applications. This study aims to develop a proton-conductive salt by simultaneously coordinating multiple acid species with heterocyclic imidazole (Imi), which possesses basic sites capable of reacting with acids. The goal is to create a highly proton-conductive composite suitable for anhydrous conditions. The mechanochemical milling method was employed to incorporate SiO2 as a second material into imidazole hydrochloride (ImiHCl). As a result, the addition of SiO2 to ImiHCl led to an enhancement in proton conductivity compared with imidazole (Im), imidazole hydrochloride (ImiHCl), and imidazole–SiO2 (Imi–SiO2). Furthermore, a method based on density functional theory (DFT) was proposed to predict the high/low proton conductivity, which exhibited good correlation with the experimentally obtained conductivity values. This DFT approach provided insights into the proton conduction mechanism. Through comprehensive physical characterizations (FT-IR, NMR, XRD, and TGA) and DFT calculations, it was revealed that the high proton conductivity observed in the corresponding xImiHCl-(100 – x)SiO2 composites (composition ratio of ImiHCl: x = 40–100) can be attributed to an increased number of proton species, accelerated proton dissociation facilitated by SiO2, and promotion of proton diffusion. Particularly, the xImiHCl-(100 – x)SiO2 (x = 60) electrolyte demonstrated the highest proton conductivity of 1.4 × 10–2 S cm–1. Subsequently, a PBI-based electrolyte membrane prepared using 60ImiHCl-40SiO2 significantly enhanced the fuel cell performance to 521 mW cm–2 under anhydrous conditions at 150 °C.

show abstract