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Controllable anisotropic growth of perovskite nanocrystals (NCs) is challenging since it is difficult to separate the nucleation and growth processes. Here, a two-step nucleation strategy is proposed to control the binding interaction between surface ligands and NCs, resulting in facet-induced coordination competition. Oleic acid as surface activated ligand leads to the formation of defective lead bromine octahedron, and the binding interaction between 4-dodecylbenzenesulfonic acid and lead atoms promotes the formation of two kinds of binding interactions. Based on this strategy, the anisotropic growth of CsPbBr3 nanoplatelet (NPLs) with adjusted length from 11.4 to 24 nm, and the evolution of NPLs from stacked to tongue-shaped have been realized. Elemental line scan reveals the sulfur atoms mainly distribute at the edge of NPLs. Furthermore, binding energy calculation and experimental results illustrate the coordination competition of different binding interaction on specific facets induces the anisotropic growth of NPLs. Importantly, strong emission anisotropy of highly ordered NPLs with polarization ratio up to 0.58 is illustrated. This work not only deepens our understanding of the controllable synthesis of perovskite NCs, but also provides a reference for the regulation of light emitting diode and soler cells. [ABSTRACT FROM AUTHOR]

By data of 10,357 individual investors from Renrendai.com, an established peer‐to‐peer (P2P) lending platform in China over the period of 2011–2014, we examine whether investors' prior investment outcomes influence their subsequent risk‐taking behavior in the credit market. We find strong evidence that a prior trading loss induces greater subsequent risk‐taking. Specifically, investors decrease their number of bids and the bidding amount; and choose listings with a lower interest rate and higher credit grade. The investors who obtain more prior gains become more cautious and take on less posterior risk. Overall, this study complements the lack of relevant research in the credit market. [ABSTRACT FROM AUTHOR]

This paper investigates expert bidding imitation in peer‐to‐peer lending platforms. We employ data from Renrendai.com, which contains information of about 170,000 investors who placed almost four million bids on 111,234 loan listings from 2010 to 2018. The experts are defined as investors who either have more central roles or who spend more time or money on the network. We find that an average investor mimics the bids of expert lenders. Inactive lenders learn top investors' lending behaviour through observational learning and then, follow their actions, although they do not know the experts' identity. Finally, we show that experts rarely imitate other experts, yet they exhibit herding behaviour. [ABSTRACT FROM AUTHOR]

This study examines the performance of a new online peer‐to‐peer (P2P) lending platform in China that relies on non‐expert individuals to screen for loans. Using the bank deposit rate as a benchmark, positive excess returns exist under the posted price mechanism, which indicates that P2P markets provide lenders with adequate profit opportunities to compensate for investment risks. Moreover, we find that loans with higher excess returns are more likely to be funded and are bid on more quickly than other loans. Finally, voluntarily disclosed soft information in the listing's description plays a significant moderating role in the lenders' decision‐making process. Borrowers who promise to repay on time are more likely to be funded and to be funded faster, but those who claim economic hardship have a lower probability of being funded. Our results provide evidence that lenders have the ability to seek excess returns in P2P lending markets and highlight that aggregating the views of peers can improve the market efficiency. [ABSTRACT FROM AUTHOR]

Understanding the subtle structure–property relationships of quantum dots (QDs) is essential for targeted modulation of optoelectronic properties, and the influences of surface defects of inorganic halide perovskite (HP) QDs are still not very clear. Here, the negative exciton trapping effects of surface halide vacancies (VX) on the photoluminescence quantum yield QY (PLQY) of HPQDs are determined by a detailed analysis of the optical parameters, exciton dynamics, and surface chemical states. Based on the fact that VX contribute greatly to nonradiative recombination processes, versatile in situ and postpassivation strategies are developed by constructing intact Pb–X octahedrons. High QYs for standard red CsPbBr1I2 (85%), green CsPbBr3 (96%), and blue CsPbBr1.3Cl1.7 (92%) emissions are achieved. The superiorities of the reduced VX are further demonstrated by high external quantum efficiency of 0.8% and a stable emission wavelength of the blue light‐emitting diodes. This study deepens the understanding of HPQDs and demonstrates the potential for the artificial control of the optical properties of HPQDs. [ABSTRACT FROM AUTHOR]