Platinum–rhodium–tin/carbon electrocatalysts for ethanol oxidation in acid media: effect of the precursor addition order and the amount of tin

Carbon-supported Pt x –Rh y –Sn z catalysts (x:y:z = 3:1:4, 6:2:4, 9:3:4) are prepared by Pt, Rh, and Sn precursors reduction in different addition order. The materials are characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy techniques and are evaluated for the electrooxidation of ethanol in acidic media by cyclic voltammetry, chronoamperometry, and anode potentiostatic polarization. The influence of both the order in which the precursors are added and the composition of metals in the catalysts on the electrocatalytic activity and physico-chemical characteristics of Pt x –Rh y –Sn z /C catalysts is evaluated. Oxidized Rh species prevail on the surface of catalysts synthesized by simultaneous co-precipitation, thus demonstrating the influence of synthesis method on the oxidation state of catalysts. Furthermore, high amounts of Sn in composites synthesized by co-precipitation result in very active catalysts at low potentials (bifunctional effect), while medium Sn load is needed for sequentially deposited catalysts when the electronic effect is most important (high potentials), since more exposed Pt and Rh sites are needed on the catalyst surface to alcohol oxidation. The Pt3–Rh1–Sn4/C catalyst prepared by co-precipitation is the most active at potentials lower than 0.55 V (related to bifunctional effect), while the Pt6–Rh2–Sn4/C catalyst, prepared by sequential precipitation (first Rh and, after drying, Pt + Sn), is the most active above 0.55 V.The authors thank the Brazilian National Council of Technological and Scientific Development-CNPq (Grants: 402243/2012-9, 303630/2012-4, 474261/2013-1, 407274/2013-8, and 310282/2013-6) for the scholarships and financial support for this work

Situational Incompetence: The Failure of Governance in the Management of Large Scale IT Projects

Part 4: IT Project ManagementInternational audienceInformation technology (IT) projects in the government (public) sector experience significant challenges. Despite decades of research, the adoption of formal methods, the use of external suppliers and packaged software, these remediation attempts have not appeared to have reduced nor mitigated the problems faced when the public sector undertakes large IT projects. Previous studies have examined the causes of IT project failure, in particular these have focused on factor analysis. A relatively limited number of studies have investigated the contribution of IT competence, and even fewer have considered the role and contribution of non-IT executives in IT project outcomes. This study sought a deeper understanding of what drives the behaviour of large scale IT projects. Of particular note was the finding by Kruger and Dunning (2009) that ‘the skills required to do the job are the same skills needed to identify competence in others’. It was this finding which was found to most influence the observed behaviours of executive leadership leading to IT project failure.This research reports on a qualitative study that investigated 181 interviews and 5,000 pages of project data drawn from a large-scale public sector IT project which resulted in a cost overrun that exceeded AUD$1 Billion. The interview transcripts and project data were analysed using an inductive case study methodology and the research process was influenced by aspects of Grounded Theory.A new Theory of Situational Incompetence has been developed as a result of the analysis. The research culminates in a proposed measurement instrument intended to gauge leadership competence in the context of increasing project size and complexity