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Defects in solution-processed perovskite films can trap photoinduced carriers, facilitate ion migration, and accelerate degradation of perovskites, thus posing a major threat to the performance of perovskite solar cells (PSCs). To address these issues, we rationally proposed a multifunctional sulfonium salt molecule, namely diphenyl-(trifluoromethyl)-sulfonium trifluoromethanesulfonate (TFS-TFMS), which was designed to chelate the detrimental defects of perovskite films using a cost-effective post-treatment method. Theoretical and experimental evidence indicated that defects on the surface and grain boundaries of perovskite films, including uncoordinated Pb2+, volatile organic cations and mobile ionic vacancies, were synergistically anchored by S＝O, –CF3 and TFS+ groups in the TFS-TFMS molecule via Lewis acid–base coordination, hydrogen bonds and electrostatic interactions, respectively. The carrier dynamic behavior and energy level alignment at the interface between perovskites and hole-transportation-layers were also significantly improved. Consequently, the power conversion efficiency (PCE) of PSCs was boosted from 21.99% to 23.56% upon the introduction of TFS-TFMS, along with a diminished hysteresis index. In addition, the TFS-TFMS modified devices without encapsulation can retain 86% and 80% of their initial PCEs under aging conditions of 40–60% relative humidity (1752 h) or heating at 85 °C (504 h), respectively. It is expected that this synergistical design strategy of fluorine-rich sulfonium salt molecules can inspire more potential multifunctional modulators for efficient and stable PSCs towards commercialization in the future. [ABSTRACT FROM AUTHOR]

We investigate the relationship between product market competition and internal corporate governance from the perspective of stock price crash risk using a sample of Chinese A-share listed firms from 2003 to 2014. We find that product market competition significantly decreases stock price crash risk and this effect is more pronounced for firms with poor corporate governance (i.e. state-owned enterprises (SOEs), firms with remote independent directors, and firms with lower managerial ownership). This pattern of evidence suggests that product market competition, as an external governance mechanism can substitute poor internal corporate governance by disciplining insiders' information hoarding and thus lead to lower stock price crash risk. The further finding that market competition improves information quality supports the information hoarding channel. Our findings hold up to a battery of robustness checks and endogeneity tests. [ABSTRACT FROM AUTHOR]

The sodium-ion battery (SIB) as a promising candidate for large-scale energy storage has attracted widespread attention in recent years. However, its practical application is plagued by the lack of suitable anode materials that can afford long cycle life, high rate capability and large capacity. Herein, we report a high-performance self-supported Bi microforest (MF) anode with Bi microtree arrays uniformly grown on porous Cu foil for SIBs. The Bi MF can be directly employed as an anode without using any binders and conductive additives. Finite-element analysis and electrochemical kinetics analyses reveal that such a tree-like microstructure facilitates fast Na+ diffusion and promotes effective stress dissipation. As a result, the Bi MF electrode shows exceptionally high rate capability (338.9 mA h g−1 at 50 A g−1 with a capacity retention of 94.2%) and excellent cycling stability (95.9% capacity retention after 1200 cycles at 1 A g−1). More importantly, by pairing the Bi MF anode with a Na3V2(PO4)3 cathode, the assembled full cell achieves a long cycle life and an inspiring energy density of 132.2 W h kg−1, showing the great potential of the Bi MF anode in sodium-ion full-cells. [ABSTRACT FROM AUTHOR]

Self-assembled monolayers (SAMs) have been successfully employed to enhance the efficiency of inverted perovskite solar cells (PSCs) and perovskite/silicon tandem solar cells due to their facile low-temperature processing and superior device performance. Nevertheless, depositing uniform and dense SAMs with high surface coverage on metal oxide substrates remains a critical challenge. In this work, we propose a holistic strategy to construct composite hole transport layers (HTLs) by co-adsorbing mixed SAMs (MeO-2PACz and 2PACz) onto the surface of the H2O2-modified NiOx layer. The results demonstrate that the conductivity of the NiOx bulk phase is enhanced due to the H2O2 modification, thereby facilitating carrier transport. Furthermore, the hydroxyl-rich NiOx surface promotes uniform and dense adsorption of mixed SAM molecules while enhancing their anchoring stability. In addition, the energy level alignment at the interface is improved due to the utilization of mixed SAMs in an optimized ratio. Furthermore, the perovskite film crystal growth is facilitated by the uniform and dense composite HTLs. As a result, the power conversion efficiency of PSCs based on composite HTLs is boosted from 22.26% to 23.16%, along with enhanced operational stability. This work highlights the importance of designing and constructing NiOx/SAM composite HTLs as an effective strategy for enhancing both the performance and stability of inverted PSCs. [ABSTRACT FROM AUTHOR]

In order to discuss the effect of different combing processing routes on polyester cotton blended fabric style, polyester and cotton were separately combed then blended to spin polyester cotton blended combed yarn according to blending ratio of 65/35. Additionally, polyester were carded, cotton were combed and blended to spin semi-combed polyester cotton blended yarn. Both the polyester cotton blended combed yarn and polyester cotton blended semi-combed yarn were processed into polyester cotton blended combed fabric and polyester cotton blended semi-combed fabric using the same weaving and dyeing processes. The two types of fabric were tested for various style parameters, including tensile, shear, bending, compression and surface characteristics using KES fabric style analyzer. The results showed that compared with polyester cotton blended semi-combed fabric, the polyester cotton combed blended fabric exhibited improvements in various style aspects. The bending rigidity was reduced 20%, bending hysteresis distance was reduced 17%, compression work ratio was reduced 22% and fluctuation of friction coefficient was reduced 18%. It is considered that the polyester cotton blended combed fabric has better qualities in terms of softness, smoothness and resilience compared to the polyester cotton blended semi-combed fabric. [ABSTRACT FROM AUTHOR]

We examine the effect of nonfamily leadership in family firms, whereby family members do not act as either a board chair or a CEO, on corporate earnings management. We find that firms with nonfamily leadership conduct significantly more earnings management than firms with family leadership, although this effect can be alleviated by more effective internal control and a stronger reputation concern. Additional analyses show that the increased related-party transactions can be one mechanism through which the nonfamily leadership increases earnings management. We further find that nonfamily leaders in family firms are on average weaker but receive higher (excess) payment than their peers in nonfamily firms, all consistent with the role of the nonfamily member as a marionette for the family's misbehaviors. Moreover, earnings management increases with the degree of family noninvolvement and is mainly driven by nonfamily chairs rather than the CEOs. Overall, our paper suggests that not having a family leader aggravates incentives for the controlling family to manage earnings to realize private benefits. [ABSTRACT FROM AUTHOR]

This study examines the voting behaviour of independent directors from academia based on manually collected voting data. We find that academic independent directors are less likely to dissent on board proposals than other independent directors, especially the directors who have fewer industry-specific experiences or have a relatively higher pay from the focal firm. The academic directors are also more likely to lose board seats after dissension, consistent with their concern of less job security as they are easily replaced. Lastly, although academic directors generally have weaker incentives to vote against insiders, they are more likely to dissent on proposals concerning related-party transactions. Overall, our study sheds new light on the role of academic independent directors in board monitoring effectiveness. [ABSTRACT FROM AUTHOR]

Research Question/Issue: This paper examines the relationship between having nonfamily members (i.e., family outsiders) as board chairs and corporate philanthropy. Research Findings/Insights: In a hand‐collected dataset of Chinese family firms, we find that firms invest less in philanthropy when the board chair is a nonfamily member. However, this impact is mitigated when the chair's discretion is restricted, as in highly visible firms or firms controlled by the founding family. The negative relation between nonfamily chairs and corporate philanthropy is also weaker when the interest of chairs is more aligned with that of the controlling family, where chairs are inside‐promoted or members of founding team, when board chairs and the families have more goal consistency, when stakeholders have higher demands for corporate social responsibility or investors care less about profitability. Further analysis shows that nonfamily chairs help firms reduce overinvestment in philanthropy, the board chair has a more salient effect than the CEO on philanthropic giving, and the results are not driven by expropriation issues of the controlling family. Theoretical/Academic Implications: Our study highlights the heterogeneity of board chairs in family firms, board chair's significant influence on a firm's social performance, and the agency problem related with the board chair, which are all underexplored topics in prior literature. Practitioner/Policy Implications: Our evidence offers insights to practitioners about the impact of board chairs on corporate philanthropy. Family firms need pay attention to the recruitment of board chairs and hold a comprehensive view of family firm professionalization as a nonfamily board chair might negatively affect firms' stakeholder relationship management but bring benefits by mitigating excess philanthropic activities. Besides, practitioners shall be aware of agency problems originating from board chairs. Incentives or monitoring over chairs might be useful to address potential conflicts of interest. [ABSTRACT FROM AUTHOR]