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Seawater electrolysis for hydrogen production represents a substantial opportunity to curtail production expenditures and exhibits considerable potential for various industrial applications. Platinum-based precious metals exhibit excellent activity for water electrolysis. However, their limited reserves and high costs impede their widespread use on a large scale. Single-atom catalysts, characterized by low loading and high utilization efficiency, represent a viable alternative, and the development of simple synthesis methods can facilitate their practical application. In this work, we report the facile synthesis of a single-atom Pt-loaded NiCoFeSx (Pt@NiCoFeSx) bifunctional catalytic electrode using a simple impregnation method on a nickel foam substrate. The resulting electrode exhibits low overpotentials for both HER (60 mV@10 mA cm−2) and OER (201 mV@10 mA cm−2) in alkaline seawater electrolytes. When incorporated into a seawater electrolyzer, this electrode achieves a direct current energy consumption of only 4.18 kWh/Nm3H2 over a 100 h test period with negligible decay. These findings demonstrate the potential of our approach for industrial-scale seawater electrolysis. [ABSTRACT FROM AUTHOR]

Students with special needs are often isolated from the rest of the class and have to attend specific courses designed for them. This report describes an action-research project with two students with a hearing impediment and who were following a course at a university of science and technology. A student with mild autism was appointed as a teaching assistant because the course teacher wanted to provide him with the opportunity to express himself and to communicate with others. The course teacher presented material by means of an interactive whiteboard and video-based coursebook to maximise student understanding and foster learning, while the autistic assistant, also using an interactive whiteboard, often helped the two students go over what they had learned. A literature review focuses on the use of an interactive whiteboard and activity-theory in education, especially with students with special needs. This paper concludes with the statement that the findings were encouragingly positive. Suggestions are made to assist teachers who would like to take further steps towards the use of computer technology in special needs education.

The use of podcasting has attracted the attention of teachers because it is content-rich and is of wide general interest. Users can listen to podcasts via the Internet or download them on to a portable music player. Some also offer video or animation to make the contents more interesting and easier to understand. Accordingly, podcasts that tend to focus on the use of vocabulary can be very effective in language learning. They help learners hear how to pronounce their words clearly and use them appropriately. In addition to the benefit of its multimodal facilities, the main advantage of podcasting lies in the variety and the control it provides. Many podcasts provide an authentic context including those which are vocationally orientated. In other words, learners can access podcasts linked to their field of study or interest. Therefore, this research project explores how podcasts in an ESL (English for specific purposes) environment can be used with foreign language learners. It then discusses learners' perspectives of podcasts related to certain subjects. Finally, it proposes a number of suggestions for practical strategies and techniques for teaching English through podcasting.

Low-energy consumption seawater electrolysis at high current density is an effective way for hydrogen production, however the continuous feeding of seawater may result in the accumulation of Cl−, leading to severe anode poisoning and corrosion, thereby compromising the activity and stability. Herein, CoFeAl layered double hydroxide anodes with excellent oxygen evolution reaction activity are synthesized and delivered stable catalytic performance for 350 hours at 2 A cm−2 in the presence of 6-fold concentrated seawater. Comprehensive analysis reveals that the Al3+ ions in electrode are etched off by OH− during oxygen evolution reaction process, resulting in M3+ vacancies that boost oxygen evolution reaction activity. Additionally, the self-originated Al(OH)n− is found to adsorb on the anode surface to improve stability. An electrode assembly based on a micropore membrane and CoFeAl layered double hydroxide electrodes operates continuously for 500 hours at 1 A cm−2, demonstrating their feasibility in brine electrolysis. Developing high-performance electrodes for catalyzing brine oxidation is essential for cost effective hydrogen production. Here, this study reveals the self-protective mechanism of CoFeAl layered double hydroxides, enabling stable operation in the presence of concentrated seawater at 2 A cm−2. [ABSTRACT FROM AUTHOR]

Anchoring noble metals to non-noble metals oxide to create single-atom catalysts (SACs) was an appealing approach to improve atomic efficiency and catalyst activity with simultaneous reduction of cost. However, knowledge of how single-atom anchors at unique loading positions and varying numbers of coordination atoms behavior in oxygen evolution reaction (OER) was still inadequate. Herein, the Ir was chosen to anchor at three-fold face center cubic (FCC) hollow sites, three-fold hexagonal close packed (HCP) hollow sites, and Oxygen Vacancy (OV) sites on Co3O4 (111) surface with different coordination environments by first-principles study of OER. The results displayed that the overpotential (η) of threefold FCC hollow sites with four coordination oxygens (FCC-4O) was 0.35 V, which was the lowest overpotential among our catalysts. The d-band center and Bader charge results demonstrated the coordination oxygen could change Ir electron structure, specifically FCC-4O, making the adsorption between the carrier and the intermediate more moderate for reducing the energy barrier of the potential-determining step. When Ir possesses five coordination oxygens, the HCP sites spontaneously transformed into the FCC sites, showing it was an unstable state. In addition, band gap studies indicated that the OV sites catalysts had a reduced band gap and stronger electron transport ability, notably for the Ir with four-coordination hydroxyl group (OV-4OH), which led to high OER performance (η = 0.46 V). Finally, the solvation effect and kinetic stability were tested, it could be found that both FCC-4O and OV-4OH showed good OER performance, especially FCC has good stability and may be more possible in experimental conditions. The figure described volcano diagram of our catalysts and the illustration of FCC sites, HCP sites, and OV sites. FCC-4O had the best OER performance among our catalysts with η = 0.35 V. [ABSTRACT FROM AUTHOR]

Water electrolysis is a crucial technology in the production of hydrogen energy. Due to the escalating industrial demand for green hydrogen, the required electrode size for a traditional alkaline water electrolyzer has been increasing. Numerous studies have focused on developing highly active oxygen evolution reaction (OER) catalysts for water electrolysis. However, there remains a significant gap between the microscale synthesis of catalysts in laboratory settings and the macroscale preparation required for industrial scenarios. This challenge is particularly pronounced in the synthesis of sizable self-supported electrodes. In this work, we employed a commercially available Raney Ni-coated Ni mesh as a precursor material to fabricate a self-supported NiFe(OH)x@Raney Ni anode with a substantial dimension exceeding 300 mm through a straightforward immersion technique. The as-prepared electrode exhibited remarkable electrocatalytic OER activity, as an overpotential of only 240 mV is required to achieve 10 mA cm−2. This performance is comparable to that of NiFe-LDHs synthesized via a hydrothermal method, which is difficult to scale up for industrial applications. Furthermore, the electrode demonstrated exceptional durability, maintaining stable operation for over 100 h at a current density of 500 mA cm−2. The large-scale electrode displayed consistent overpotentials across various areas, indicating uniform catalytic activity. When integrated into an alkaline water electrolysis device, it delivered an average cell voltage of 1.80 V at 200 mA cm−2 and achieved a direct current hydrogen production energy consumption as low as 4.3 kWh/Nm3. These findings underline the suitability of electrodes for industrial scale applications, offering a promising alternative for energy-efficient hydrogen production. [ABSTRACT FROM AUTHOR]