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Converting carbon‐based molecular fuels into electricity efficiently and cleanly without emitting CO2 remains a challenge. Conventional fuel cells using noble metals as anode catalysts often suffer performance degradation due to CO poisoning and a host of problems associated with CO2 production. This study provides a CO2‐emission‐free direct formaldehyde fuel cell. It enables a flow of electricity while producing H2 and valuable formate. Unlike conventional carbon‐based molecules electrooxidation, formaldehyde 1‐electron oxidation is performed on the Cu anode with high selectivity, thus generating formate and H2 without undergoing CO2 pathway. In addition, the fuel cell produces 0.62 Nm3 H2 and 53 mol formate per 1 kWh of electricity generated, with an open circuit voltage of up to 1 V and a peak power density of 350 mW cm−2. This study puts forward a zero‐carbon solution for the efficient utilization of carbon‐based molecule fuels that generates electricity, hydrogen and valuable chemicals in synchronization. [ABSTRACT FROM AUTHOR]

Development of high-efficiency and cost-effective carbon capture technology is a central element of our effort to battle the global warming and climate change. Here we report that the unique high-flux and high-selectivity of electrochemical silver-carbonate dual-phase membranes can be retained for an extended period of operation by overcoating the surfaces of porous silver matrix with a uniform layer of Al2O3 thin-film derived from chemical vapor deposition. [ABSTRACT FROM AUTHOR]

Abstract: H2-mesoporphyrin IX and Zn-mesoporphyrin IX have been investigated as sensitizers for the titanium dioxide (TiO2) film electrode to construct a new two-compartment photoelectrochemical biofuel cell (PEBFC). The PEBFC can convert the light and chemical energy to electricity by consuming photons and oxidizing glucose. The two sensitizers are similar with two carboxyl anchoring groups, except that the central hydrogen atoms in the H2-mesoporphyrin IX are replaced by zinc. To determine how cell performance is affected by the sensitizer, we analyze the photochemical and photoelectrochemical properties of the two sensitizers by physical characterization and photoelectrochemical experiments. The UV–Vis absorption spectra and X-ray photoelectron spectra (XPS) indicate that the interactions between the sensitizer and TiO2 decrease in the order of H2-mesoporphyrin IX > Zn-mesoporphyrin IX. The interactions are also determined by Fourier transform infrared (FTIR) spectra which indicate that the two sensitizers are adsorbed on the TiO2 film through the carboxyl groups. The photovoltaic characteristics show the Zn-mesoporphyrin IX is less effective in comparison with the H2-mesoporphyrin IX, since the Zn-mesoporphyrin IX enhances the back electron-transfer process, producing lower IPCE and current. These results reveal that the H2-mesoporphyrin IX is a more efficient sensitizer compared with the Zn-mesoporphyrin IX for the PEBFC. [Copyright &y& Elsevier]

Abstract: The methanol electro-oxidation behaviors on the Pt–MoO x /C catalysts with various compositions were investigated and compared to those of Pt/C catalyst by cyclic voltammetry and chronoamperometry. The Pt–MoO x /C catalysts were prepared by depositing Pt on the MoO x /C support obtained by precipitation-reduction method in advance. The physical properties of the prepared catalysts were characterized by XRD, XPS, EDX and TEM. From the results of XRD and TEM, it was shown that the MoO x /C support facilitated the dispersion of Pt particles. All the Pt–MoO x /C catalysts showed relative lower Mo contents comparing to their nominal values. No PtMo alloy was formed in these catalysts, which were affirmed by XPS and XRD. It was found that all the Pt–MoO x /C catalysts showed higher mass activity (normalized to the mass of Pt) but lower specific activity (normalized to the electrochemical active surface areas) for methanol oxidation than the Pt/C catalyst. With the increase of Mo contents in Pt–MoO x /C catalysts, the activities of Pt–MoO x /C catalysts decreased. Combined with the composition and structure analyses, the differences in methanol oxidation on these catalysts were attributed to the interaction between the Pt particles and the MoO x /C support. It was suggested that the Pt metal–MoO x /C support interaction resulted in two effects. One was decreasing the Pt particle size; the other was decreasing the specific activities of these catalysts for methanol oxidation. Comprising these two contradictory effects, the mass activities of these catalysts for methanol oxidation increased. [Copyright &y& Elsevier]

Converting carbon-based molecular fuels into electricity efficiently and cleanly without emitting CO 2 remains a challenge. Conventional fuel cells using noble metals as anode catalysts often suffer performance degradation due to CO poisoning and a host of problems associated with CO 2 production. This study provides a CO 2 -emission-free direct formaldehyde fuel cell. It enables a flow of electricity while producing H 2 and valuable formate. Unlike conventional carbon-based molecules electrooxidation, formaldehyde 1-electron oxidation is performed on the Cu anode with high selectivity, thus generating formate and H 2 without undergoing CO 2 pathway. In addition, the fuel cell produces 0.62 Nm 3 H 2 and 53 mol formate per 1 kWh of electricity generated, with an open circuit voltage of up to 1 V and a peak power density of 350 mW cm -2 . This study puts forward a zero-carbon solution for the efficient utilization of carbon-based molecule fuels that generates electricity, hydrogen and valuable chemicals in synchronization., (© 2023 Wiley-VCH GmbH.)