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A coral-like dendritic AgPt alloy catalyst with 50 at% Ag is fabricated by a facile self-growth-assisted reduction route at room temperature and exhibits enhanced performance for both the HER and MOR in acidic electrolyte.

Direct methanol fuel cells (DMFCs) have attracted considerable scientific interest because of their ease of operation and implementation; however, poor electrocatalytic activity and durability are the main hindrances for their commercial feasibility. Moreover, the deactivation of active Pt sites, due to the coverage of CO-like species during the electrochemical oxidation reaction, significantly degrades the electrochemical surface area (ECSA). In the present work, stable Pt-supported tin-modified indium oxide (ITO) was synthesized as a promising electrocatalyst towards the methanol oxidation reaction (MOR) in DMFCs. It was found that 20 wt% Pt/ITO yielded much higher current density (∼0.71 mA/cm2) than the state-of-the-art carbon-supported Pt (E-TEK) electrocatalyst. Furthermore, the If/Ib ratio, which featured the CO tolerance of the electrocatalyst, of 20 wt% Pt/ITO was found to be ∼1.42, which is ∼1.5-fold higher than that of 20 wt% Pt/C (E-TEK). Chronoamperometry results indicated that 20 wt% Pt/ITO manifested much higher stability than 20 wt% Pt/C (E-TEK).

High cost and poor durability of Pt-based electrocatalysts are the main challenges for future commercialization of direct ethanol fuel cells (DEFCs). In the present work, a stable and effective Pt/Ti0.8W0.2O2 electrocatalyst toward ethanol electrooxidation reactions (EORs) was prepared by utilizing the attributes of noncarbon catalyst supports and low Pt loading. The 18.5 wt % Pt/Ti0.8W0.2O2 electrocatalyst was successfully fabricated through a simple and rapid microwave-assisted polyol route (ethylene glycol was used as a reducing agent). In comparison with a conventional 20 wt % Pt/C electrocatalyst, the as-prepared 18.5 wt % Pt/Ti0.8W0.2O2 electrocatalyst resulted in much lower onset potential, higher If/Ib value, and superior stability toward EOR, which can be ascribed to the synergistic effect between Pt nanocatalyst and the Ti0.8W0.2O2 catalyst support. Therefore, these findings imply that 18.5 wt % Pt/Ti0.8W0.2O2 is a promising anodic electrocatalyst and possesses the ability to replace Pt/C electrocatalysts in the future.

To overcome the disadvantages of commercial carbonaceous catalysts in direct methanol fuel cells (DMFCs), novel Pt/Ti1–xIrxO2 catalysts are fabricated in this study. Simultaneously, the influence of the Ir composition in the support on the electrocatalytic activities and physicochemical properties of Pt/Ti1–xIrxO2 catalysts is also evaluated. Ti1–xIrxO2 materials with the tunable Ir composition (x = 0.1, 0.2, 0.3) synthesized via a simple and green hydrothermal route exhibited much higher electrical conductivity and surface area than the undoped TiO2. Furthermore, the well-distributed Pt nanoparticles (NPs) with small sizes (∼3 nm) over supports were obtained by using a modified chemical reduction route. Electrochemical results revealed that a series of 20 wt. % Pt/Ti1–xIrxO2 catalysts exhibited superior durability and electrochemical activity toward the methanol oxidation reaction to the commercial 20 wt. % Pt/C (E-TEK) catalyst. According to these results, Ti1–xIrxO2 materials seem to be very promising as a stable catalyst support in the harsh medium of DMFCs.

Correction for ‘Facile room-temperature fabrication of a silver–platinum nanocoral catalyst towards hydrogen evolution and methanol electro-oxidation’ by Hau Quoc Pham et al., Mater. Adv., 2022, DOI: 10.1039/d1ma01077h.

Finding out robust active and sustainable catalyst towards alcohol electro-oxidation reaction is major challenges for large-scale commercialization of direct alcohol fuel cells. Herein, a robust Pt nanowires (NWs)/Ti0.7W0.3O2 electrocatalyst, as the coherency of using non-carbon catalyst support and controlling the morphology and structure of the Pt nanocatalyst, was fabricated via an effortless chemical reduction reaction approach at room temperature without using surfactant/stabilizers or template to assemble an anodic electrocatalyst towards methanol electro-oxidation reaction (MOR) and ethanol electro-oxidation reaction (EOR). These observational results demonstrated that the Pt NWs/Ti0.7W0.3O2 electrocatalyst is an intriguing anodic electrocatalyst, which can alter the state-of-the-art Pt NPs/C catalyst. Compared with the conventional Pt NPs/C electrocatalyst, the Pt NWs/Ti0.7W0.3O2 electrocatalyst exhibited the lower onset potential (~0.1 V for MOR and ~0.2 for EOR), higher mass activity (~355.29 mA/mgPt for MOR and ~325.01 mA/mgPt for EOR) and much greater durability. The outperformance of the Pt NWs/Ti0.7W0.3O2 electrocatalyst is ascribable to the merits of the anisotropic one-dimensional Pt nanostructure and the mesoporous Ti0.7W0.3O2 support along with the synergistic effects between the Ti0.7W0.3O2 support and the Pt nanocatalyst. Furthermore, this approach may provide a promising catalytic platform for fuel cell technology and a variety of applications.

The issue of CO2 emissions, the major caused leads to climate change has always been of particular interest in the context of the industrialization process and urbanization taking place more and more complex. Ho Chi Minh City is a large city of Vietnam with a high rate of urbanization and thus the CO2 emissions management process needs to be studied. In this work, we have developed the Geographic Information System (GIS) to build the mapping of CO2 emission from population of Metropolis, case study of Ho Chi Minh City in Vietnam for the first time. The mapping CO2 emissions for Ho Chi Minh city from the population have been calculated from human respiration and combustion gas in daily activities. We found that the highest level of CO2 emissions is located the western suburbs of the city including Binh Tan district, Tan Phu district, Tan Binh district, Go Vap district, District 12, Binh Chanh and Hoc Mon district. In seven districts with emission levels high, Binh Tan has the highest CO2 emissions and opposite Can Gio district has the lowest CO2 emission due to Can Gio district is a district adjacent to the sea and mainly mangroves forests, traffic condition is not conducive to the process of industrial development, therefore no attract workers from the others district, the province as Binh Tan district and local people trend to industrial zones making the district’s population the lowest. The results of this work can make reasonable policy in the management and reduction of CO2 emissions for future cities with low carbon city.