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A titanium-doped Ce 0.8 Sm 0.2 O 1.9 composite is developed as an anode component of low temperature solid oxide fuel cells running on methane fuel. Crystallographic parameters of (Ce 0.8-x Ti x )Sm 0.2 O 2-δ (0.00 0.8-x Ti x )Sm 0.2 O 2-δ composites are applied to an anode-supported single cell consisting of Ni-(Ce 0.8-x Ti x )Sm 0.2 O 2-δ anode/Ce 0.8 Sm 0.2 O 1.9 electrolyte/La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ cathode. Catalytic properties of Ni-(Ce 0.8-x Ti x )Sm 0.2 O 2-δ are inspected with the electrochemical performance and performance stability of the cells in dry methane fuel. The cell with Ni-(Ce 0.73 Ti 0.07 )Sm 0.2 O 2-δ (x = 0.07) anode displays a low polarization resistance and an optimum maximum power density (679 mW cm −2 at 600 °C). A performance stability investigation indicates that the cell exhibits a fairly low degradation rate of 3 mV h −1 during a 31 h operation in dry methane. These findings suggest the application potential of the titanium doped Ce 0.8 Sm 0.2 O 1.9 for the anode of solid oxide fuel cells.

This short communication describes a novel MoO2-based cathode and its potential application for solid oxide electrolysis cells. Electrochemical performances of the MoO2-based cathode are investigated with respect to a commercial Ni/YSZ-based cathode for both co-electrolysis (of H2O and CO2) and electrolysis of only CO2 at 750 °C. Under the co-electrolysis mode, the MoO2-based cell and the Ni/YSZ cell show a similar electrochemical performance, while in the CO2 electrolysis mode, the MoO2-based cell demonstrates a much improved electrocatalytic activity compared with the Ni/YSZ cell. This improved electrochemical activity of the MoO2-based cathode under the CO2 electrolysis mode is further investigated by its electrochemical impedance spectroscopy (EIS) study. According to our EIS study, the polarization resistance of the MoO2-based cell is 67% lower than that of the Ni/YSZ-based cell under the open circuit potential. A performance stability study indicates that the MoO2-based cell exhibits a relatively low performance degradation under the CO2 electrolysis mode during its 10-h constant voltage test, and low carbon amount (6.6 wt.%) is detected after the performance stability measurement. These findings suggest the advantages of applying the MoO2-based cathode for the CO2 electrolysis.

Electricity is the most commonly used form of energy for artificial lighting in modern society. Despite a rapid growth in the rate of electrification, 9% of electrified Indian households in our six sampled states continued to use kerosene as their primary lighting fuel in 2018. This appears as a puzzle considering the benefits of electric lights. Using a panel survey of rural households in six states in India, we examine why some grid-connected households primarily used kerosene lamps for illumination. We use a logistic regression model to test our hypothesis regarding the relationship between primary lighting choices and electricity quality. The results show that household primary lighting choices are correlated with nighttime duration of electricity service, daytime duration of electricity service, and the number of days without any electricity connection, at the 99% confidence level. Among these three factors, nighttime duration of electricity service has the greatest impact. To further promote the use of electric lights, intensive schemes to improve electricity quality are needed.

The deactivation of bifunctional Ni/HZSM-5 catalysts is essentially due to the formation of heavy secondary products (i.e., coke) in the hydrodeoxygenation (HDO) of bio-oil. Coke deposited on the Ni/HZSM-5 catalyst was characterized using analytical techniques, including Fourier transform infrared spectroscopy (FTIR), thermogravimetric (TG) analysis, and transmission electron microscopy (TEM). The type and quantitative distribution of the deposited coke on the Ni/HZSM-5 catalyst were determined by the dissolution of the aluminum–silicate matrix in a hydrofluoric acid solution. The composition of soluble coke was obtained by gas chromatography–mass spectrometry (GC–MS) measurements. It is found that coke can be divided into soft coke, hard coke, and graphite at different reaction temperatures. Organic reactants can be transformed into soft coke and hard coke by different chemical reactions, such as alkylation, aromatization, hydrogen transfer, and dehydrogenation. The quantitative distribution between solu...

This short communication describes the performance of a solid oxide fuel cell (SOFC) fueled by directly feeding premium gasoline to the anode without using external reforming. The novel component of the fuel cell that enables such operation is the mixed conductivity of MoO 2 -based anode. Using this anode, a fuel cell demonstrating a maximum power density of 31 mW/cm 2 at 0.45 V was successfully fabricated. Over a 24 h period of operation, the open cell voltage remained stable at ∼0.92 V. Scanning electron microscopy (SEM) examination of the anode surface pre- and post-testing showed no evidence of coking.

A NiMo–Ce0.5Zr0.5O2-δ (NiMo-CZ) catalyst has been developed for gasoline-fed solid oxide fuel cells (SOFCs). To apply the catalyst on a button-type single cell, the NiMo-CZ is deposited on top of conventional Ni-yttria-stabilized zirconia (YSZ) anode as a catalytic internal micro-reforming layer. The NiMo-CZ layer is effective in increasing the gasoline conversion and enhancing the yields of both H2 and CO at 750 °C. On the other hand, due to the high mechanical stress induced from the constrained sintering with a thicker catalyst layer, only a limited amount of catalyst (~20 mg) could be applied over the conventional button-type cell, which is not beneficial for enhancing overall cell performances. To overcome this issue, a tubular single cell configuration is adopted that allowed for higher catalyst loadings. By introducing higher catalyst loadings (~80 mg) in the vacant tubular channel of the single cell, the gasoline conversion, H2 yield, and CO yield all improve while cell lifetime increases by 42% compared to the performance of the button-type cell. The results suggest the potential of the NiMo-CZ catalyst for gasoline-fed SOFCs, and it demonstrates the advantage of the tubular single cell configuration for incorporating higher catalyst loadings for internal catalytic fuel reforming.