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Nickel was electrodeposited on porous Ag/GDC (silver/Ce 0.9 Gd 0.1 O 2-x ) scaffolds and dense Ag/GDC composites for the fabrication of SOFC electrodes and catalytic membranes respectively. To control the distribution and amount of nickel deposition on the Ag/GDC surfaces; first, a systematic cyclic voltammetry study of nickel electrodeposition from a Watts bath on silver foils was carried out to understand the influence of operating conditions on the electrodeposition process. From the cyclic voltammetry study, it can be concluded that suitable operating conditions for nickel electrodeposition into porous Ag/GDC scaffolds and catalytic membranes are: 1.1 M Ni 2+ concentration in Watts bath; deposition potential between −0.65 to −1.0 V vs. Ag/AgCl; a temperature at 55 • C; sodium dodecyl sulfate (SDS) as the surfactant; pH 4.0 ± 0.2 and an agitation rate of 500 rpm. It was observed that the nickel surface microstructure changed with the deposition current densities due to the co-evolution of H 2 . Pulse and continuous electrodeposition modes allow nickel to be deposited throughout porous Ag/GDC scaffolds and onto catalytic membranes. The pulse electrodeposition mode is favored as this is shown to result in an even Ni distribution within the porous scaffolds at minimum H 2 pitting. Nickel is used as a catalyst and current collector in electrochemical energy conversion systems such as solid oxide fuel cells (SOFCs), electrolysers, and as a catalyst in catalytic membranes ( Figure 1). Conventionally, Ni is incorporated into SOFC anodes by mechanically mixing NiO and ionic conductive materials such as yttriastabilized zirconia (YSZ) and Ce 0.9 Gd 0.1 O 2-x (GDC), then sintering at high temperature. However, the use of relatively large volumes of Ni (∼30 vol%) needed to achieve adequate electronic conductivity in the electrodes will affect the stability of cell microstructure under redox cycling. Recent advances in the manufacture of SOFC anodes via infiltration of Ni nitrate solution into a porous backbone (scaffold) have made it possible to achieve an excellent performance with a significantly reduced amount of nickel.1,2 However, repeated infiltration involving heating and cooling cycles is a lengthy and energy consuming process, presenting challenges to its industrial application. An alternative is to use electroless and electrodeposition techniques, which offer the potential to accelerate the incorporation of Ni into porous scaffolds at room or near-room temperature. The electroless deposition of Ni is well known and it is a simple process used to coat any substrate, however the use of boron-or phosphorus-based reducing agents in this technique is unsuitable for fuel cells due to adverse catalytic effects of the residues.3 Alternatively, hydrazine has been used as the reducing agent in the past years 4-6 yet its high toxicity may not be suitable for large production.Catalytic membranes have shown their potential to reform methane to syngas (CO+H 2 ) by coupling oxygen separation from air and catalytic partial me...

Regular water quality monitoring of water bodies is essential to ensure it is within the allowing standard limits. The development of a simple and low-cost water quality measurement device for real time monitoring using Internet of Things (IoT) technology is presented in this study. Kolora meter is an alternative to the existing commercial monitoring devices. It was developed using the open-source platform Arduino UNO model and NodeMCU board as the microcontroller and Wi-Fi connection respectively. Two sensors such as temperature and turbidity were selected to be installed in the early stage of Kolora meter development. The physical parameters (temperature and turbidity) of water were measured and the measured data collected are able to be viewed and monitored on the mobile phone using Kolora Mobile Application via Wi-Fi connection. Therefore, this surface water quality device has potential to be applied in real time monitoring for early pollution detection and during COVID-19 pandemic spread due to limited movement.

Summary High‐temperature solid oxide fuel cells (HT‐SOFCs) generally operate at 800°C to 1000°C and intermediate temperature SOFCs (IT‐SOFCs) at 600°C to 800°C. Reducing the SOFCs operational from high to ITs results in many issues mainly at the cathode site. One of the shortcomings that have been addressed is high polarization losses associated with oxygen reduction reaction (ORR) and degradation of La1−xSrxCo1−yFeyO3−δ (LSCF) cathode materials. Strontium (Sr) has been discovered to segregate and inhibit the surface‐active site for the ORR under specified conditions (temperature, relative humidity, and suppressing activity). It enriched the surface, formed Sr‐rich secondary phases, and eventually changes the composition and the structure of the perovskite surfaces. Therefore, this review aims to summarize the occurrences of Sr segregation at the LSCF cathode surfaces as a function of operating conditions and their effects on the material performance. In addition, the characterization techniques utilized to investigate the Sr segregation, and strategies for Sr segregation mitigation are also discussed.

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An indigenous purple non-sulfur bacteria Rhodopseudomonas palustris PBUM001 was used to produce hydrogen gas via batch photofermentation of palm oil mill effluent (POME). The photofermentation hydrogen production was carried out in a 5-l reactor (B. Braun Biostat® B) with a working volume of 3.5 l (height: 39 cm and diameter: 16 cm) under anaerobic condition. The stirred tank reactor (STR) was conducted at temperature, 30 ± 2 °C; POME concentration, 100% (v/v); light intensity, 4.0 klux; pH 6, inoculum size, 10% (v/v); agitation rate, 250 rpm, and operated for 66 h. Two sets of experiments were run in STR (R1 and R2) and the data obtained were used for kinetic study of photofermentation hydrogen production. Unstructured models were used to describe the bacterial growth, substrate consumption, and hydrogen gas production by R. palustris PBUM001. The discrepancy between the proposed model and the experimental data in simulating hydrogen production from POME by R. palustris PBUM001 was measured by using residual sum of squares (RSS). Logistic model could be adopted to describe the kinetics of bacterial growth (RSS: 0.3039–0.2313) and the proposed model for substrate consumption agreed well with the experimental data obtained in this study as shown by its RSS value of 19.1319 and 26.8259 for R1 and R2, respectively. A modified Leudeking-Piret model was applied for the data fitting to determine the relationship between the cell growth and photofermentation hydrogen production (RSS: 1.3267–26.3741).

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