Unique catalyst Pd NPs/Fe2O3 exhibits outstanding EOR and ORR activity in alkaline environment: a Pt and carbon free approach.

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The present study explores the contributory benefits of transition metals (TM) and their oxides (TMO) along with metal NPs toward oxygen reduction reaction (ORR) in alkaline medium for low-temperature direct ethanol fuel cells (DEFCs). The metal–co-metal (Pd–Co) NPs were casted over a TMO support, α-MnO2, by a green synthetic approach without using any reducing agent, whereby the introduction of >30% Co in the Pd matrix formulates the optimal catalyst composition Pd69Co31/MnO2 that not only reduces the cost and eliminates the carbon support but also ensures the catalytic efficacy for the binary system. The studies involved morphology determined through electron microscopy and electrochemical characterization with the help of potentiodynamic polarization and rotating disk electroderotating ring–disk electrode techniques. The diminution of ORR overvoltage by ∼85 mV with respect to Pd/C establishes the catalytic pre-eminence of the nanostructured Pd69Co31/MnO2 manifested by the low yield of H2O2 in ORR and an appreciable power density output of 45.5 mW/cm2 for a single test cell at 40 °C. The autocatalytic peroxide removal capacity of the MnO2 support and synergistic interaction within Pd–Co NPs for driving the ORR catalytic ability to a substantial level are the testaments to the major utility of the combinatorial (metal–TM–TMO) ensemble.

A blank slate may seem like an innovator's opportunity, but twentieth-century designer Charles Eames was right: There is no design without constraints. That blank slate means you have to start at the beginning, figuring out the right questions to ask in order to understand what is and isn't known, who can contribute, and how to define the goal. The absence of those constraints quickly became apparent when design became part of Dell's challenge to become the "greenest" technology company on the planet. We recognized that we would need a framework of constraints in which to innovate, but consider that there is no exact formula or calculator for green design in the technology space. Although there are certifications that monitor and regulate practices in the industry, the need exists for greater clarity.Last year, Dell announced a global challenge to address this head-on. We began by engaging customers in forums and communities through our digital properties, such as the Direct2Dell and IdeaStorm blogs we developed, which had grown into case studies of effective engagement with customers. We knew we did not want to own the knowledge domain; rather, we wanted to involve a broader community in understanding what it means to design greener IT. For this goal, we recognized that we needed help from a broad audience to identify the scope of the challenge and create the knowledge base. The result was ReGeneration, a global initiative aimed at people of all ages who care about sustaining the world's natural environment. Dell Chairman and CEO Michael Dell first introduced ReGeneration on World Environment C A S E S T U D Y n its quest to become the greenest technology company on the planet, Dell held a design competition. Interestingly, the computer concepts submitted not only explored multifaceted approaches to sustainability, but also, as Rajib Adhikary describes, became the nexus for a global conversation on green design and a source for many lessons on business and sustainability.