Investigation of Trap States in Organic Semiconductors for Organic Solar Cells Applications

Energy is an essential resource for supporting everyday life and economic development. Among numerous approaches which people use to collect energy, photovoltaics stands out for two factors: it allows to obtain electricity by exploiting an abundant source of solar energy and it does it in an environmentally friendly way. In recent years, the development of organic solar cells gained a large interest as this technology offers low-cost, light-weight and flexible devices. Moreover, in contrast to inorganic semiconductors, organics offers a variety of materials with optoelectronic properties tailored in a wide range. To further increase the solar cell efficiency, it is important to study charge-carrier transport, that is strongly influenced by the presence of trap states. Organic semiconductors are particularly prone to the formation of such states due to the weak attraction between molecules. No investigation of trap states has been done for oligothiophenes so far in spite of their excellent performance in organic solar cells. In this work, the blend of the dicyanovinyl end-capped oligothiophene DCV5T-Me and C60 is studied on the presence of trap states. This material showed high efficiencies in vacuum-processed small-molecule organic solar cells with a PCE of the best single-junction cell of 8.3% and a fill factor (FF) of 65.8%. The traps are investigated by using impedance spectroscopy (IS) and thermally stimulated currents (TSC) measurements. The blend DCV5T-Me:C60 (2:1, 80°C) contains two types of electron and a set of hole trap states. A deep Gaussian distributed electron trap at 470 meV (with respect to the transport level) is observed in the blend by IS measurements. Its origin is attributed to the distortion of the natural morphology in the C60 phase due to the intermixing of donor and acceptor molecules. Moreover, a shallow Gaussian distributed electron trap at 100 meV (with respect to the transport level) is observed in neat C60 by IS measurements. Finally, a distribution of shallow trap states with depth below 200 meV (with respect to the transport level) and overall trap density of Nt > 8.7E+16 cm^−3 is indicated in the blend by TSC measurements. The majority of these defects is attributed to hole trap states in the DCV5T-Me phase. The deep electron traps at 470 meV reduce the free charge carrier density and act as recombination centers, leading to trap-assisted recombination. According to drift-diffusion simulations, these deep traps lead to the relative reduction of FF of about 10%. The hole trap states in DCV5T-Me can explain a reduced hole mobility of μh=7E−5 cm^2/(Vs), which is limiting for the solar cell performance as it is two orders of magnitude lower than the electron mobility

Autodidactic approach: forming self-directed efl learning readiness

The article deals with the problem of preparing intending EFL teachers at teacher training universities for professionally-oriented selfdirected learning readiness in the field if foreign languages. For this purpose the brief outline of basic characteristics of such a readiness is given on the basis of analysis of scientific literature on the problem. The authors of the article share their positive experience in applying the autodidactic approach to teaching English to students of the English Department in the Institute of Foreign Languages of Ural State Pedagogical University. The research results prove that it is possible to effectively form students’ self-directed EFL learning readiness by means of increasing their methodological awareness in the field of teaching foreign languages and applying their knowledge and skills to the process of self-directed learning itself both within and beyond the classroom environment. The three stages of the approach are described in detail: learning, self-directed learning, and peer-teaching. The final stage is considered professionally-oriented since it allows students to act in the capacity of future teachers of English but, here, within the classroom environment. The approach is realized according to five consequent principles: intersubject coordination, tutoring, individually oriented assessment, heuristic and multitasking principles. The principles by their nature go back to the student-centered and activity approach, the integrative-differentiative approach and the contextual approach which serve as the methodological bases of the autodidactic approach developed

Autodidactic English for intending efl teachers: a coursebook structure

The article deals with the problem of structuring a coursebook on English for intending EFL teachers at teacher training universities. Considering the main requirements for their professionally-oriented training in Russia, self-directed language learning readiness is analyzed on the basis of scientific literature on the problem. As one of the possible solutions of the problem the authors of the article suggest using an autodidactic approach to teaching English and share their positive experience in applying it to practice at the Institute of Foreign Languages of Ural State Pedagogical University. The autodidactic approach is based on intersubject coordination, tutoring, individually oriented assessment and heuristic principles and presupposes the realization of three subsequent stages: learning, self-directed learning, and peer-teaching. The application of the autodidactic principles and the stages of the approach finds reflection in the structure of the coursebook on English “Autodidactic English for Intending EFL Teachers” which is given in detail in the article. The coursebook structure is modular, the three basic modules being “Autodidactic Awareness” (which assists students at the stage of learning), “Brush up Your Study Skills” (at the stage of self-directed EFL learning) and “Teach and Learn” (at the stage of peer-teaching). The main modules are supplemented by “Language Portfolio” and “Assess Your Self-Directed Learning Readiness” modules which help both the teacher and students to plan their interaction and assess the results of their work. The research results prove that it is possible to effectively form students’ self-directed EFL learning readiness by means of increasing their methodological awareness in the field of teaching foreign languages and applying their knowledge and skills to the process of self-directed learning both within and beyond the classroom environment

Specifics of the development of students’ creative abilities in the context of higher education

This study examines the problems of the development of students’ creative abilities, their structure and specifics, similarities and differences from creativity. The aim of the research is theoretical and empirical consideration of the specifics of students’ creative abilities and their development. The problems of the essence of creative abilities, the role of their formation in the young age, specific methods and techniques are revealed. The research methodology and its algorithm were selected due to the purpose of the study. Experimental work included a complex psychological and pedagogical experiment, consisting of the indicative, formative and control stages. The study of students’ creative abilities was carried out on the basis of the Institute of Foreign Languages of the Federal State Autonomous Educational Institution of Higher Education “The Peoples’ Friendship University of Russia” (RUDN). An experimental and a control group were formed, each included 45 people, the sampling is valid for all significant characteristics. The results of the study allow us to conclude that the training forms are especially effective in the development of students’ creative abilities. The level of development of the teacher’s creative abilities is a significant factor in the formation of students’ creative abilities.

Specifics of the development of students’ creative abilities in the context of higher education

This study examines the problems of the development of students’ creative abilities, their structure and specifics, similarities and differences from creativity. The aim of the research is theoretical and empirical consideration of the specifics of students’ creative abilities and their development. The problems of the essence of creative abilities, the role of their formation in the young age, specific methods and techniques are revealed. The research methodology and its algorithm were selected due to the purpose of the study. Experimental work included a complex psychological and pedagogical experiment, consisting of the indicative, formative and control stages. The study of students’ creative abilities was carried out on the basis of the Institute of Foreign Languages of the Federal State Autonomous Educational Institution of Higher Education “The Peoples’ Friendship University of Russia” (RUDN). An experimental and a control group were formed, each included 45 people, the sampling is valid for all significant characteristics. The results of the study allow us to conclude that the training forms are especially effective in the development of students’ creative abilities. The level of development of the teacher’s creative abilities is a significant factor in the formation of students’ creative abilities.

The improvement of students’ stress resistance with the help of the development of self-regulation during university studies

The article is devoted to the urgent problem of the formation of stress resistance in university students with the help of self-regulation training. The study highlights the specifics of examination of this phenomenon in modern science, the structure of stress resistance, and the significance and characteristics of the development of students’ stress resistance. The article also emphasizes the fact that the development of the given asset is especially effective within the self-regulation training, which is an effective method for improving the emotional-volitional component of students’ personality. The article indicates that the developed self-regulation of students and, in particular, personal self-regulation are important for the development of stress resistance. The research is aimed at studying the specifics of university students’ stress resistance with the help of self-regulation training. To achieve the goal of the research, the experiment aimed at studying the state and dynamics of students’ stress resistance was developed and carried out. The research methodology and its algorithm were selected, which included a complex psychological and pedagogical experiment and tracking the state and dynamics of stress resistance before and after the formative influence. The study was carried out at the Department of Social Pedagogy of the Institute of Foreign Languages, Peoples’ Friendship University of Russia. The study involved 56 students, the sample is representative in terms of gender and other characteristics. The results of the study allow the authors to conclude that self-regulation training is an effective method for the formation of stress resistance in students.

Specifics of the development of students’ creative abilities in the context of higher education

This study examines the problems of the development of students’ creative abilities, their structure and specifics, similarities and differences from creativity. The aim of the research is theoretical and empirical consideration of the specifics of students’ creative abilities and their development. The problems of the essence of creative abilities, the role of their formation in the young age, specific methods and techniques are revealed. The research methodology and its algorithm were selected due to the purpose of the study. Experimental work included a complex psychological and pedagogical experiment, consisting of the indicative, formative and control stages. The study of students’ creative abilities was carried out on the basis of the Institute of Foreign Languages of the Federal State Autonomous Educational Institution of Higher Education “The Peoples’ Friendship University of Russia” (RUDN). An experimental and a control group were formed, each included 45 people, the sampling is valid for all significant characteristics. The results of the study allow us to conclude that the training forms are especially effective in the development of students’ creative abilities. The level of development of the teacher’s creative abilities is a significant factor in the formation of students’ creative abilities.

Formation of students’ social competence in the context of additional vocational education

The article is devoted to the urgent problem of the formation of students’ social competence while receiving additional vocational education. The study highlights the specifics of the examination of this phenomenon in modern science and the significance of the development of students’ social competence. The article also emphasizes the fact that the development of the given asset is especially effective within the training activity in addition to the traditional educational environment of a university, in particular, in the context of the various forms of additional vocational education. The research is aimed at studying the specifics of the formation of students’ social competence while receiving additional vocational education. To achieve the goal of the research, an experiment aimed at studying the state and dynamics of students’ social competence was developed and carried out. The research methodology and its algorithm were selected, which include a complex psychological and pedagogical experiment and tracking the state and dynamics of social competence before and after the formative influence. The study was carried out at the Department of Social Pedagogy of the Institute of Foreign Languages of the Peoples’ Friendship University of Russia. The study involved 40 students; the sample was representative in terms of gender and other characteristics. The results of the study allow concluding that training is an effective method for the formation of students’ social competence in the context of additional vocational education. The results of the experiment and their interpretation confirm this hypothesis.

Classification of written translation skills for English legal discourse

The article deals with the content of notions "English legal discourse", "translation difficulties", "translation strategy", "translation tactics", "translation skills". Description is given of the complex of written translation strategies for English legal discourse. The authors suggest developing groups of translation skills at pre- translation, translation and post- translation stages

Improvement of value orientations in the process of forming the professional competence of teachers

This study examines the issues of value orientations of a teacher and their development as an integral part of professional competence. We drew attention to the relationship between the value orientations and the value sphere within the process of teacher’s professional development, the conditionality of professional competence by the value system. The aim of the research is the theoretical and empirical study of value orientations as a component of the professional competence of teachers. Particular attention is paid to the role and significance of creativity in the teaching performance. Based on the analysis of current literary sources, we examined the phenomenon of professional creativity of a teacher, made an attempt to define this concept and considered its structure and structural components. The research methodology and its algorithm were selected due to the purpose of the study. Experimental work included a complex psychological and pedagogical experiment and diagnostics of the stated parameters before and after the implementation of the advanced training. The study was carried out on the basis of the Institute of Foreign Languages of the Federal State Autonomous Educational Institution of Higher Education “The Peoples’ Friendship University of Russia” (RUDN). The results of the study allow us to conclude that there is a significant relationship between the professional creativity of a teacher and the effectiveness of professional performance, which is confirmed by the results of statistical processing of the data obtained. In the Russian psychological and pedagogical literature on the problem of professional competence two basic concepts are discussed, competence and competency. Researchers argue that these concepts are multidimensional and systemic in nature. In Russia, the difference between these concepts is most thoroughly substantiated in the glossary of the Federal State Educational Standard. It is indicated that competencies consist of knowledge, skills and abilities, as well as of practical experience. The ability to apply them in professional activities is called competence.