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All-polymer solar cells (all-PSCs) have seen rapid progress enabled by the development of high-performance polymer acceptors. Most polymer acceptors are based on the monomers of a classic small molecular acceptor (SMA) named Y6 by polymerizing at the position of the end groups, forming an “end-to-end” linkage. In this work, we report a completely different “core-to-core” linking mode by polymerizing the Y-series monomers at the central core position instead. This innovative strategy results in a drastically altered molecular configuration that resembles a “double decker,” with intramolecular packing between different monomer units in the same polymer. The overall molecular packing is improved, benefiting charge delocalization and charge transport. As a result, the PffBQx-T-based ternary blend achieved an outstanding efficiency of 18.7%, attributed to the enhanced absorption response, improved packing, and efficient charge dynamics. Our work demonstrates a novel polymer design rationale that serves as a promising avenue toward highly efficient and stable all-PSCs.

Organic photovoltaic (OPV) is one of the most promising technologies for powering indoor electronic devices. The high-performance indoor organic photovoltaics (IOPV) require medium bandgap materials to absorb visible light efficiently and reduce energy loss. However, state-of-the-art A-DA’D-A type small molecule acceptors (SMAs) have absorptions in the near-infrared region which mismatches with the room light. In this work, two medium bandgap A-DA’D-A type SMAs BTOL-Br and DFOL-Br were synthesized by a molecular synergetic modification strategy for the applications in IOPV. Our results show that DFOL-Br with replacing the A’ unit of benzothiadiazole in BTOL-Br by difluorine substituted benzene ring, exhibits blue-shifted absorption spectra and an up-shifted lowest unoccupied molecular orbital (LUMO) energy level than those of BTOL-Br. When blending the SMAs with a polymer donor PBQx-TCl, the DFOL-Br-based film shows more ordered molecular packing and suitable phase separation. As a result, the DFOL-Br-based device achieves a higher indoor efficiency of 26.8% under a 2600 K light-emitting diode lamp at 2000 lux than that of the BTOL-Br-based one (23.2%). This work indicates that the synergetic modification is an effective strategy for preparing medium bandgap A-DA’D-A type SMAs, which may become a useful SMA design guideline for developing high-performance IOPVs.

Background/Context For centuries, the notions of citizenship and citizenship education have been associated with the nation-state and civic elements. However, since the late 20th century, these traditional notions have been challenged by globalization. In the discourse of globalization, citizenship, and citizenship education, some scholars suggest a simplistic replacement or shift from national citizenship to global citizenship, regional citizenship, or local and group identities. Against these simplistic, single-leveled approaches is the argument for both the continuing importance of nation-specific characteristics of citizenship and the strong need to diversify the nation-state-oriented and civic-specific framework to form multileveled and multidimensional ones. They accommodate individuals’ engagement in the various domains of human activities and their memberships at various levels, ranging from individual to community, local, national, and international or global ones. Some scholars have advocated a multidimensional model of citizenship education by regrouping human relationships and activities into four major dimensions—personal, social, spatial, and temporal—which can intersect with various levels in the multilevel polity. However, these general, static frameworks are not backed by strong empirical evidence and do not explain the complexity of interplay among different actors at the same level and/or between levels.Purpose The purpose of the article is twofold. First, it aims to provide empirical evidence for the general framework of multileveled and multidimensional citizenship education by assessing students’ views of citizenship in a multileveled polity with reference to Hong Kong and Shanghai in China. Second, with the help of the comparative study, the article is intended to supplement the general framework by proposing a theoretical framework that explains the complex interplay of different actors in their choices of citizenship elements from a multileveled polity.Setting The study took place in three public junior secondary schools in Shanghai and three aided secondary schools in Hong Kong and assessed their students’ views of the global, national, local, and personal-social domains of multiple identities in a multileveled polity.Research Design The study adopted a mixed methodology of observations, questionnaires, and interview surveys to collect data.Data Collection and Analysis Data are drawn from questionnaires completed by 1,402 students attending Grades 7–9, and 38 interviews with principals, teachers, and students from both societies between 2002 and 2003.Conclusions/Recommendations The study shows that although students of Hong Kong and Shanghai were aware of having multiple citizenships, some of their views of the relative importance of, and the interrelationships among, four dimensions of citizenship differed. The patterns of their perceptions of multiple citizenships reflect similarities and differences in the organization of citizenship education between schools in Hong Kong and Shanghai, the nation-state's influences on local citizenship curricula, and local governments’ development considerations in remaking collective identity. With the help of the comparative study, the article supplements the general framework by proposing a theoretical framework for interpreting citizenship and citizenship education as dynamic, context-bounded, and multi-leveled social constructions reinvented through the intertwined interactions of different actors in response to social changes, including globalization.

The lack of public funding available for schools in China is a serious problem. To alleviate this situation, the government urges schools to engage in ‘creating income’ by running factories, opening shops, renting out school premises, etc., in order to advance educational provision and improve teachers’ welfare. This article reports upon a recent study of 21 secondary schools in an urban district of Guangzhou. It describes and analyzes how the practices identified above can improve facilities and equipment, boost morale, facilitate innovation and increase autonomy at the school level. In addition, it examines some of the problems that may be generated by such practices.