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Molybdenum disulfide (MoS2) has gained a lot of interest as a potassium storage material with a high anode capacity. However, the slow reaction kinetics and its highly unstable structure prevent the full realization of its electrochemical performance during the insertion and extraction of K+. Herein, sulfur vacancy-modified MoS2 nanolayers grown coaxially with an external carbon coating and internal carbon nanotube support (denoted as C–MoS2−x@CNTs) are designed as anode materials for potassium storage. This unique structure enables fast K+ reaction kinetics facilitated by S vacancy engineering, uniform growth of MoS2 nanolayers controlled by internal carbon nanotubes, and the stability of the complete electrode preserved by the encapsulation of carbon. Therefore, the prepared C–MoS2−x@CNTs reveal a high rate performance value of 180.9 mA h g−1 (5 A g−1) with a reversible capacity value of 323.8 mA h g−1 (50 mA g−1). It sustains a capacity of 141.2 mA h g−1, exhibiting excellent cycling stability, even after 300 cycles at a current density of 2 A g−1. [ABSTRACT FROM AUTHOR]

The ability of Engineering graduates to function as successful professionals depends not only on technical disciplinary knowledge but also on a wide range of professional competencies. Students’ often react differently to educators attempts to develop professional competencies compared to technical competencies. Understanding the nature of these reactions is important if we are to design the most effective educational approaches to the development of professional competencies. In this paper we report on an exploratory factor analysis that used data from a detailed survey of students (N = 339) to identify underlying factors that provide insights to understand the variations in student reactions. A set of five factors were identified from this analysis: capability; learning experience; learning outcomes; employment experience; environment. Two of these factors (learning experience and environment) also exhibited significant differences in the impact between professional and technical competencies. A number of implications for educational design were explored. [ABSTRACT FROM AUTHOR]

Introduction: Engineering students should develop critical-thinking skills and insist on appropriate performance levels both from themselves and from their colleagues during their training. In doing so, they will adopt critical attitudes toward their own and others' work. This will help them to successfully perform their future professional work with the highest standards. Methods: In this research, peer- and self-assessments of in-class presentations through a survey-based program were used to analyze the development of critical-thinking skills among engineering students. The program included two key features: firstly, formative assessments were repeatedly conducted over time; secondly, teachers' ratings were provided to students as comparative benchmarks. This approach encouraged students to reflect on their ratings over time using the reference of the teacher. Results: From a general perspective, the analysis of survey responses showed that students assigned lower ratings in assessments conducted at a later stage, despite receiving higher ratings from their teachers over time. Therefore, students became more demanding throughout the experience in spite of the increased quality of their work according to the teachers' assessments. Moreover, students tended to closely attune their evaluations to their teachers' ratings. Comparing peer- and self-assessments, it was noted that students were more demanding toward the work of their peers in the long term, and especially their ability to explain concepts, than they were toward their own work. Nevertheless, high temporary increases were observed in students' own self-assessments of presentation-file quality. Finally, students did not conduct overall assessments with the same level of demand as their teachers at any time during the experience. Discussion: The results demonstrate that this program and similar initiatives are useful to help engineering students to develop critical-thinking skills and to broaden their expectations with respect to their own and their colleagues' work. However, other relevant aspects could be evaluated in lengthier programs, such as whether the students' levels of critical thinking and expectations are maintained when the comparative reference of a teacher's assessment is unavailable. [ABSTRACT FROM AUTHOR]