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High school students' lack of science career intentions has attracted the attention of stakeholders and researchers in many fields. Studies relevant to the formation of science career perceptions and the development of science careers have played crucial roles in the science education research field. The current study draws on two widely applied theories in investigating students' science career intentions: social cognitive career theory (SCCT) and science capital theory. The study employs quantitative- dominant mixed methods, including structural equation modelling and case studies. Through the construction of models, this study demonstrates the processes by which Chinese high school students (age 16-18) form their science career intentions. These formation processes consist of a set of interactions between contextual factors (family science capital) and personal cognitive factors (e. g. self-efficacy, interest). This study provides evidence of the applicability of both science capital theory and SCCT in the Chinese context. In addition, at the theoretical level, the current study complements science capital theory and SCCT. It reveals that aspects of personal agency, for example self-efficacy, can mediate the relation between students' family science capital and their science career intentions. Science capital theory posits an indirect relationship between family science capital and science career intentions; the current study's findings complement this observation and strengthen its explanation. For SCCT, the present study investigates the disputed questions from previous literature about some key variables: self-efficacy, interest, and learning experiences; and it refines the understanding of these variables. This study offers insights to help understand the formation processes of Chinese high school students' science career intentions. The study thereby contributes to the development and refinement of relevant theories, and it also provides applied implications for educational policy and future studies.

The demand for clean and sustainable energy has set the stage for the development of affordable and efficient electrocatalysts for hydrogen generation. MoS2, a typical transition metal dichalcogenides (TMDs), is a promising electrocatalyst for hydrogen evolution reaction (HER) owing to its tunable atomic structure. However, several key challenges, including low electrical conductivity and the limited active sites of hydrogen bonding. remain in MoS2 based electrocatalysts, which hinders its potential applications in water splitting. In this work, in order to improve the catalytic activity of MoS2, several innovative strategies have been utilized to synergistically increase active sites, reduce resistance, and lower the energy barrier of hydrogen absorption. In detail, 4 effective approaches have been designed to fabricate optimized MoS2 nanosheets for highly efficient hydrogen production, including nanoparticle decoration, phase transformation, element substitution, and single atom intercalation. The MoS2 nanosheets show excellent catalytic performance with high current density, low onset potential, reduced Tafel slope, and good catalytical stability. The underline mechanism of enhanced hydrogen production is systematically investigated, and the remarkable HER performances can be attributed to the synergistic effects of the modified MoS2. It is found that through rational control of morphology and electronic structure, the adsorption and desorption process of H atoms on MoS2 could be balanced, and the Gibbs free energy of hydrogen binding is moderate with a value relatively close to the Pt electrodes. Besides, more active sites arise from phase transformation or unsaturated single metal atoms, which also promotes the HER process dramatically. Finally, nanoparticle decoration and element substitution increase the electrical conductivity, and specific doping element leads to optimized energy level and reduced work function, facilitating the electron transfer. The controlled design strategy may also be applied to develop other TMDs based electrocatalysts with high HER activity and opens up a new direction to engineer electrochemical properties of functional materials.

In this day and age, the research of Diluted Magnetic Semiconductors (DMS) has evolved into a significant field in Material Science. It is widely investigated because of its remarkable advantage of combining properties of both semiconductors and ferromagnetism. Indeed, EuS, Mn doped GaAs and InAs as well as oxide semiconductor based room temperature DMSs are all breakthroughs in improving magnetic performance and are milestones in DMS fabrication. However, oxide semiconductor based DMSs such as Co doped ZnO and Fe doped TiO2 are facing a dilemma that the magnetic performance examined could possibly be the characteristic of transition metal itself rather than doping in DMS material as a result of dopant accumulating effects. In this sense, a new fabrication method –neodymium and cobalt co-doped ZnO nanowire – is observed, which to large extent, would minimize the accumulation of dopants effectively, and provides relatively satisfactory magnetic property of DMS materials. In this project, we first introduce the concept of DMS and its applications. Secondly, we focus on ZnO based DMS thin film materials to look into the fabrication process, structure and various properties, followed by applicable ways to increase doping concentration and Curie temperature. In addition, we discuss about the disputes of conventional DMS and possible solutions – nanowire magnetic semiconductors. At last, we carry out experiments of Nd and/or Co co-doped ZnO nanowires and investigate the relevant properties.