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In order to improve cost competitiveness and the further application of metal-supported cells, it is important to explore cathodes suitable for low-temperature sintering. However, decreasing cathode sintering temperature while maintaining robust interface of cathode/electrolyte and decent electrochemical performances is challenging for solid oxide fuel cells. Herein, by combining the Pechini method with one-pot method, La 0.6 Sr 0.4 CoO 3-δ @ Gd 0.1 Ce 0.9 O 2-δ (LSC@GDC) composite cathodes are prepared and investigated, compared with mechanically mixed LSC-GDC cathodes. At the cathode sintering temperature of 800 °C, the LSC@GDC cathode single cells perform better performances, with deceased resistances, improved power density outputs and better feasibility to wide oxygen partial pressures from 0.21 atm down to 0.03 atm. The optimum composition of 70:30 wt% for LSC@GDC is proposed. The anode supported single cell with LSC@GDC30 cathode exhibits a maximum power density of 0.789 W/cm2 and 0.545 W/cm2 at 750 °C, under cathode oxygen partial pressure of 0.21 atm and 0.03 atm, respectively. Moreover, the low temperature sintered LSC@GDC50 cathode performs decent durability during repeatedly controlled thermal cycling over 10 times. • LSC@GDC cathode is successfully prepared by novel two-step one-pot method. • The cathode sintering activity improves as well as interface contact. • The cell performance in harsh condition is dramatically enhanced. • The cell exhibit decent long-term durability and thermal cycling stability. [ABSTRACT FROM AUTHOR]

Hydrogen-rich gas production from reforming of naphthalene as a typical tar model compound was investigated under catalytic, plasma and plasma-catalytic systems. The effect of Gd promoter and solvent on naphthalene decomposition and gaseous products within the reforming reaction was studied. The catalysts were prepared by the thermal fusion method and characterized by XRD, XPS, SEM, BET, TEM, TG and H 2 -TPR. Compared to catalytic systems and plasma systems, the plasma-catalytic system shows the highest naphthalene conversion, as well as highest yield of hydrogen-rich gas on account of the synergetic effect of plasma and catalyst. Ni–Gd/SiO 2 @Al 2 O 3 catalyst exhibits superior catalytic activity than that on Ni/SiO 2 @Al 2 O 3 , due to higher dispersity of nickel species and reducibility of catalysts, as well as more Ni0 species and more surface oxygen species. No sintering and no coke formed on the fusion used catalyst owing to low content and high dispersion of nickel species. Maximum both naphthalene conversion and H 2 yield were observed on Ni-10Gd catalyst, about 89 % and 0.17 mol/mol-naphthalene, respectively. Furthermore, the presence of OH· radicals originating from methanol and the subsequent methanol reforming reaction play a pivotal role in augmenting naphthalene conversion and facilitating the formation of H 2 , CO, and CH 4. [Display omitted] • Ni-10Gd catalyst showed the highest conversion in plasma reforming of naphthalene owing to synergetic effect. • Gd enhances the dispersity and reducibility of catalyst, Ni0 species and surface oxygen species, as well as the naphthalene disintegrates. • Fusion catalysts exhibited high resistance to carbon deposition and sintering. • More OH· radicals in methanol contribute to the activity in plasma-catalytic system. [ABSTRACT FROM AUTHOR]

The practical applications of graphitic carbon nitride (g-C 3 N 4) for photocatalytic hydrogen evolution is strictly hindered by the low surface area, poor light harvesting capability and detrimental recombination of photoexcited charge carriers. Herein, using melamine as precursor and metal hydride (i.e., CaH 2) as active agent, we facilely incorporate various types of defects (i.e., nitrogen (N) vacancies (V N), cyano groups (C N) and surface absorbed oxygen species(O abs)) into g-C 3 N 4 within a single step. The as-prepared material (denoted as MM-H) exhibits narrowed bandgap, promoted photoexcited electron-hole separation rate and facilitated charge transfer kinetics with enlarged BET surface area and massive porosity. As a result, a prominently enhanced photocatalytic H 2 productivity efficiency (1305.9 μmol h−1g−1) is shown on MM-H. This performance is better than that of g-C 3 N 4 with CaH 2 post-treatment (617.3 μmol h−1g−1) and raw bulk-C 3 N 4 (178.2 μmol h−1g−1). This work opens up a new dimension for designing high performance g–C 3 N 4 –based catalysts targeting various photocatalytic processes. Image 1 • A strategy with the assist of CaH 2 is proposed to synthesize defective g-C 3 N 4. • Various types of defects are introduced into catalyst (MM-H) in one step. • The MM-H shows manipulated porosity and modulated band structure. • The MM-H exhibits an over 7 times enhancement in photocatalytic H 2 generation. [ABSTRACT FROM AUTHOR]

Biomass is frequently used to produce CO and H 2 together with undesirable by-products containing CO 2 and liquid tar by pyrolysis and gasification. This leads to decreased energy efficiency and increased maintenance costs. This study investigated the reforming of biogas and tar, respectively, using non-thermal plasma featuring dielectric barrier discharge (DBD). The gas surrogates studied were CH 4 and CO 2 , and toluene was used as a substitute for tar. During reforming of biogas, CO or H 2 was added to the CH 4 and CO 2 to investigate their effects on CH 4 and CO 2 conversion. Both the discharge power and gas components influenced the conversion of CH 4 and CO 2 . The conversion efficiency of CH 4 and CO 2 and the selectivity of H 2 and CO both increased with the discharge power while reforming the mixture of CH 4 and CO 2 . The maximum conversion efficiency of CH 4 and CO 2 and selectivity of CO and H 2 were obtained with a CH 4 :CO 2 ratio of 1:2. During reforming of toluene, the conversion efficiency of toluene reached a maximum value of 90% and the production yields of H 2 , CO, and CO 2 reached respective maximums of 0.79, 2.24, and 1.51 mol/mol-toluene at a discharge power of 90 W and temperature of 300 °C. Higher temperatures of 400–500 °C did not favour toluene destruction due to the thermal breakdown of the quartz dielectric and the rapid decrease in the discharging intensity. In addition, reaction mechanism for reforming of both biogas and toluene was proposed to improve our understanding of the reforming process in DBD plasma. [ABSTRACT FROM AUTHOR]