Search

Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell (PCFCs) practically. The current study investigates the effect of alumina on the structural, morphological, electrical, and electrochemical properties of CeO2. Lattice oxygen vacancies are induced in CeO2 by a general doping concept that enables fast ionic conduction at low-temperature ranges (300–500°C) for PCFCs. Rietveld refinement of the X-ray diffraction (XRD) patterns established the pure cubic fluorite structure of Al-doped CeO2 (ADC) samples and confirmed Al ions' fruitful integration in the CeO2 lattice. The electronic structure of the alumina-doped ceria of the materials (10ADC, 20ADC, and 30ADC) has been investigated. As a result, it was found that the best composition of 30ADC-based electrolytes induced maximum lattice oxygen vacancies. The corresponding PCFC exhibited a maximum power output of 923 mW/cm2 at 500°C. Moreover, the investigation proves the proton-conducting ability of alumina-doped ceria-based fuel cells by using an oxide ion-blocking layer. [ABSTRACT FROM AUTHOR]

The use of ceramic semiconductors to serve as an efficient proton conductor is an evolving approach in the novel emerging field of semiconductor protonic fuel cells (SPFCs). One of the most critical challenges in SPFCs is to design a sufficient proton-conductivity of 0.1 S cm−1 below <600 °C. Here we report to tune the perovskite BaSnO 3 (BSO), a semiconductor single-phase material, to be applied as a proton-conducting electrolyte for SPFC. It was found that the oxygen vacancies play a vital role to promote proton transport while the electronic short-circuiting issue of BSO semiconductor has been justified by the Schottky junction mechanism at the anode/electrolyte interface. We have demonstrated a SPFC device to deliver a maximum power density of 843 mW cm−2 with an ionic conductivity of 0.23 S cm−1 for BSO at 550 °C. The oxygen vacancy formation by increasing the annealing temperature helps to understand the proton transport mechanism in BSO and such novel low-temperature SPFC (LT-SPFC). [Display omitted] • Semiconductor BaSnO 3 tuned to be a proton conductor. • Single-phase semiconductor BaSnO 3 developed as the functional electrolyte for SPFC. • BaSnO 3 reached a high proton conductivity of 0.23 S cm−1 at 550 °C. • BaSnO 3 electrolyte fuel cell has shown high-power output of 843 mW cm−2 at 550 °C. [ABSTRACT FROM AUTHOR]

An ionic-conducting electrolyte mainly governs the solid oxide fuel cell performance. In this work, a mixed conductor NdBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ was tuned as an electrolyte via compositing with a proton conductor BaZr 0.3 Ce 0.6 Y 0.1 O 3- δ (BZCY), which realizes an ionic conductivity of 0.16 S cm−1 at 550 °C along with fuel cell power density of 470 mW cm−2. The 10 wt.% proton conducting BZCY can not only effectively block the electronic conductivity of NBSCF, but also greatly improve its ionic conductivity and the corresponding device's power output. The interfacial conduction could take a crucial role in the ion transporting process of BZCY-NBSCF composite. These interfaces or nanoscale grain boundaries formed amongst two phases keep excellent capability for designing and creating high performance electrochemical devices along with high-power density. • A mixed ionic electronic conductor NBSCF was tuned as an electrolyte via BZCY. • The 10 wt% BZCY effectively suppressed the electronic conductivity of NBSCF. • BZCY–NBSCF cell exhibited an enhanced ionic conductivity of 0.16 S cm−1 at 550 °C. • BZCY–NBSCF cell showed a power density of 470 mW cm−2 at 550 °C. • The interfacial conduction could take a crucial role in the ion transporting process. [ABSTRACT FROM AUTHOR]

The interfacial properties of electrolyte materials have a crucial impact on the ionic conductivity of solid batteries and solid oxide fuel cells. Here we construct cuprospinel CuFe 2 O 4 (CFO)–ZnO composite as a functional electrolyte for fuel cell device. In an optimal composition of 0.3CFO-0.7ZnO electrolyte fuel cell, the maximum power output of 675 mW cm−2 is obtained at 550 °C. The electrical properties and electrochemical performance are strongly dependent on the ratios between CFO and ZnO in CFO-ZnO composite. Notably, surprising fuel cell performance with high ionic conductivity is attained by constructing this p-type CFO composited with n-type ZnO. Proton conduction was further verified experimentally. The interfacial ionic conduction pathway between the two constituent phases plays a vital role to enhance the proton conductivity, and the bulk p-n heterojunction can block internal electronic pass. An excellent current and power densities of CFO-ZnO composite are observed along with a high conductivity of 0.35 S·cm-1 at 550 °C. This work opens a new perspective for the semiconductor materials that can widely be developed for electrolytes, based on their tunable band structure. • CFO–ZnO heterostructure composite was developed as the functional electrolyte. • 0.3CFO-0.7ZnO achieved super proton conductivity of 0.35 S·cm-1 at 550 °C. • Fuel cell-based on 0.3CFO-0.7ZnO demonstrated high performance. • Bulk p-n heterostructure effect of CFO-ZnO resulted in high fuel cell performance. [ABSTRACT FROM AUTHOR]

Semiconductor ionic materials (SIM) have recently gained broad attention due to their unique structural and chemical properties that enable efficient proton transport, making them promising materials for advanced fuel cell applications. This mini-review provides an overview of the proton transport phenomena in SIM and discusses their significance and future perspectives. We discuss the different types of SIMs, their proton transport mechanisms, and the factors that affect their performance. Furthermore, we emphasize the correlation between traditional perovskite oxides and SIMs and how this can be leveraged to improve the development of more advanced proton conductors for fuel cells. Also, we have highlighted the Proton-coupled electron transfer (PCET) mechanism in SIM. This mini-review provides a comprehensive overview of the current state of this emerging field, including its scientific foundations, future prospects, and applicable materials, technologies, devices, and basics for proton ceramic fuel cells (PCFCs). • This review covers efficient proton transport in SIM for fuel cell applications. • Discussed SIM protons transport's relevance, prospects, and factors. • To develop fuel cell proton conductors, we study Perovskite-SIM interactions. • This review covers PCET methods, challenges, and SIM's future. [ABSTRACT FROM AUTHOR]

The Central Asia and South Asia have become pivotal in the contemporary global politics. The closing of the twentieth century and the beginning of the twenty-first century have developed complex political conditions in the region due to changed geo-political circumstances which has involved South Asia and Central Asia as well. The object of the paper is to analyze that the’ Glocalization of politics’ in South Asia and Central Asia focuses on the concept of thinking global and acting local. It my overcome a complex of geopolitical, logistical, and economic factors which are a barrier in inter-regional connectivity and to transport the natural resources of Central Asian states to the global market in order to meet the world’s growing energy demands. Though Central Asia has abundant of natural resources, yet its geopolitical conditions have made it difficult for transporting and marketing them to the world economic market. The main problem that foreign investors are facing in the Central Asia is that how to transport the energy reservoirs from these landlocked states to the world market. The transportation route is of great geopolitical significance. The regional and global actors are in pursuit of their own national interests and to get politico-economic benefits from these two strategically important regions. The presence of regional and global competitors has aggravated the affairs of both regions. The research methodology is descriptive and analytical and the conclusion of this research paper is that the’ Glocalization of politics’ in South Asia and Central Asia is inversely proportional to the inter-regional connectivity. [ABSTRACT FROM AUTHOR]

Natural clay minerals have been applied to various energy fields due to their low cost, good stability, and abundance of resources, but few of them have been investigated for fuel cell application. Proton ceramic fuel cell, one of the most promising sustainable-energy-conversion technologies, has attracted a lot of attentions because it possesses high ionic conductivity at relatively low temperatures (<600 °C). However, the characteristics of expensive construction cost and high temperature operation hinder the development and industrialization of fuel cell. In this paper, natural clay minerals palygorskite (PAL) and Na 0.60 CoO 2 (NCO) nanosheets composite were synthesized via an electrostatic adsorption method, and used as the electrolyte of fuel cell. NCO/PAL demonstrated a high conductivity of 0.27 S∙cm−1 at 550 °C and the maximum power output of 641 mW cm−2 was achieved for NCO/PAL cell. The mechanism of proton transport at the interface of NCO/PAL semiconductor-insulator composite was discussed. [Display omitted] • Natural PAL was composited with NCO nanosheets via a facile electrostatic attraction method. • PAL/NCO composites were used as the electrolyte for advanced fuel cells at low temperature. • PAL/NCO cell reached a conductivity of 0.27 S∙cm−1 and the maximum power output of 641 mW cm−2 at 550 °C. • Proton transport at the interface of NCO/PAL semiconductor-insulator composite was proposed. [ABSTRACT FROM AUTHOR]

Nowadays, semiconductor ionic materials have drawn significant attention for developing new electrolytes in low temperature solid oxide fuel cells (LT-SOFCs). Here we investigate the effect of nickel doping on ionic conductivity of Sm 2 O 3 as an electrolyte material for low temperature SOFCs. The amount of Ni ion doping has an intense effect on the electrochemical properties and power generation. An optimized composition of 10 mol% nickel doped samarium oxide (10NSO) as an electrolyte in the fuel cell has a high open circuit voltage (OCV) of 1.09 V and a notable power output of 1080 mW cm−2 at 520 °C. Further investigation revealed that the 10NSO displays a superior ionic conduction up to 0.26 S cm−1 at 520 °C. Moreover, the cell demonstrates high stability up to 80 h. The high electrochemical property and good stability recommend that the NSO is a favorable candidate for symmetrical SOFC electrolyte. • Insulating Sm 2 O 3 doped with NiO was developed as a novel electrolyte in LT-SOFC. • Proton conduction was discovered in the NiO-Sm 2 O 3 system. • Ionic conductivity of Ni-doped Sm 2 O 3 could reach to 0.26 S cm−1 at 520 °C. • 10 mol% Ni-doped Sm 2 O 3 achieved a maximum power density of 1080 mW cm−2 at 520 °C. [ABSTRACT FROM AUTHOR]

Ultra-wide bandgap semiconductor Ceria oxide attracts tremendous interest because of its high stability and electrical properties. The ionic transport properties of CeO 2 have tremendously been elaborated in terms of electrolytes, especially using bulk doping like Sm doped Ceria and gadolinium doped Ceria, but challenges remain. In this work, we propose the surface doping of Sn into CeO 2 for the engineering of the electronic structure of CeO 2 with a focus on surface properties. The Sn doping into CeO 2 enables the Fermi-level to lower level, which further induces a local electric field, dramatically enhancing the surface proton transport at the surface and interface. Furthermore, higher concentrations of Oxygen vacancies and lattice disturbance on the surface layer are mainly ascribed to surface modification, which eventually promotes proton transport. The prepared fuel cell device based on Ce 0.9 Sn 0.1 O 2 as an electrolyte has delivered a total high performance of 905 mW cm−2 and proton performance of 787 mW/cm2 along with an ionic and protons conductivity of 0.21 and 0.19 S cm−1 at 520 °C. The surface doping of Sn in CeO 2 builds continuous surfaces as proton channels for high-speed transport. This work presents a reasonable methodology to develop high-performance, low-temperature ceramic fuel cells. [Display omitted] • CeSnO 2 was synthesized using the sol-gel technique. • The designed cell has a high ionic conductivity of 0.21 S/cm at 520 °C. • The proposed device has delivered a remarkable power output of 905 mW/cm2 520 °C. • Formation of BIEF due to surface doping dramatically enhances the surface's proton transport. • The DFT calculation was performed to assist the experimental results. [ABSTRACT FROM AUTHOR]

Exploring high conductive materials is still a challenge for high performance intermediate-temperature fuel cells. In this study, two-dimensional LiAl 0.5 Co 0.5 O 2 (LACO) nanosheets coated by a compatible amorphous LiAlO 2 (LAO) layer are evaluated as proton/Li+ conductor electrolyte. The fuel cell in which the LAO-LACO is used as electrolyte could deliver the maximum power output of 1120 mW cm−2 at 550 °C. The LAO coating enhances not only the ionic conductivity by modifying the space-charge regions, but also improves the LACO's chemical stability and device performance. Kelvin probe force microscopy further detected a local electric field (LEF) built in the LAO-LACO coating confines protons at the interface to transport fast. Such heterostructure with the LEF accelerating mechanism presents a novel approach for developing high-performance intermediate-temperature fuel cells. • LACO nanosheets coated by LAO was developed as the functional electrolyte for PCFCs. • Fuel cell based on LACO modified by LAO achieves a maximum performance of 1120 mW cm−2 at 550 °C. • A local electric field (LEF) built in the LACO modified by LAO exhibits a H+/Li+ ionconductance at the interface. [ABSTRACT FROM AUTHOR]

Perovskite oxides show high electrocatalysis behavior for energy-related applications due to their reactivity, adjustable properties and impurity tolerance. It is very important to improve the slow kinetics and long-term stability of perovskite oxides. The ability of perovskite oxides to accommodate more metallic element inside the crystal structure without compromising the matrix gives a chance to engineer the catalytic properties for various energy applications. In the perovskite structure, the transition metal at the B-site can come out at the surface upon reduction forming catalytically active nanoparticles. This is known as exsolution. Generation of different kinds of metal or alloy nanoparticles on the perovskite surface gives the opportunity of tailoring electrochemical properties for outstanding performance. The exsolution process creates active interfaces which also helps to enhance the performance and stability. The advancements in this area will drive this process further for application in different sustainable energy technologies. A report combining all the advancements and applications of exsolution in recent years may be helpful to understand the process in a more detail way. In this review, a broad overview of the exsolution process of perovskite oxides, its sustainable electrochemical energy systems are discussed. • Exsolution of perovskite oxides and its energy-related applications are discussed. • Common features, mechanism & driving forces of exsolution are discussed in detail. • The article provides fundamental understanding of the process. • It gives knowledge to select suitable perovskite oxides for specific application. [ABSTRACT FROM AUTHOR]

As an electrolyte, enough ionic conductivity, either proton (H+) or oxide (O2−) conduction, has demanded the better performance of low-temperature (especially below 550 °C) solid oxide fuel cell (LT-SOFCs). Notably, that either conductivity, higher performance, reliability, or higher cost is hampering the LT-SOFC marketing. In our current subject, we report the La-doped BZY proton conductor as an electrolyte has exhibited high ionic conductivity of 0.15 S/cm with a higher performance of 0.78 W/cm2 at 550 °C. Also, the performance of LBZY is superior to the un-doped BZY electrolyte. Such high performance mainly ascribed due to the doping of La into BZY. Besides, the mechanism for high ion conductivity is explained. This work manifests that using the LBZY semiconductor perovskite as an electrolyte is more suitable for fuel cell technology. Image 1 • The La-doped BZY (La-BZY) perovskite was synthesized using the sol-gel method. • La-BZY was applied as an electrolyte material for low-temperature solid oxide fuel cells (LT-SOFCs). • The device contains (La-BZY) electrolyte has delivered the maximum power output 0.78 W/cm2 with high OCV 1.04 V. • A lower value of ohmic resistance and grain boundary resistance may provide the fast ions transport path. • The La-doped BZY has verified to possess the dominant proton (H+) conduction. [ABSTRACT FROM AUTHOR]

In recent years, ceramic cells based on high proton conductivity have attracted much attention and can be employed for hydrogen production and electricity generation, especially at low temperatures. Nevertheless, attaining a high power output and durability is challenging, especially at low operational temperatures. In this regard, we design semiconductor heterostructure SFT-ZnO (SrFe 0.3 TiO 3 -ZnO) materials to function as an electrolyte for fuel cell and electrolysis applications. Using this approach, the functional semiconductor heterostructure can deliver a better power output and high ionic and proton conductivity at low operational temperatures. The prepared cell in fuel cell mode has demonstrated excellent performance of 700 mW cm -2 and proton performance of 540 mW cm -2 at the low temperature of 520 °C, suggesting dominant proton conduction. Further, the prepared cell delivers exceptional current densities of 1.18 and 0.38 A cm -2 (at 1.6 and 1.3 V, respectively) at 520 °C in the electrolysis mode. Our electrochemical cell is stable in fuel and electrolysis mode at a low temperature of 500 °C.