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[Purpose/Significance] The online public opinions of emergencies are usually uncontrollable. To explore the influencing factors and the configuration function of the online public opinion dissemination of emergencies in colleges and universities can provide certain basis for the management and control of the online public opinions of emergencies in colleges and universities. [Method/Process] Based on the five forces model of online public opinions, combined with the actor network theory, the influence of opinion leaders, netizens' attention, media participation, event duration, university types and event nature were selected as the anaphylactic variables of the influence of university emergency online public opinion events. Qualitative comparative analysis of fuzzy sets was used to analyze 32 emergency cases in universities from 2019 to 2020. [Result/Conclusion] The results show that a total of four conditional groups of states that generate high influence of online public opinions on university emergencies were obtained: The influence of opinion leaders and netizens' attention play a key driving role in public opinion dissemination. Media participation is an important factor to promote the high influence of public opinions; The shorter the duration of the event, the lower the impact; The higher the severity of the event, the more likely it is to cause high public opinion influence. Therefore, in the process of public opinion dissemination, the role of opinion leaders and media should be played correctly, the guidance of netizens should be strengthened, and the coping mechanism of online public opinion should be improved.

Core‐shell structured bimetallic platinum‐metal (Pt−M) nanoparticles, as a new class of active and stable nanocatalysts, have shown many advantages in increasing the utilization of precious Pt and improving electrocatalytic performances. Here, a core‐shell Pt3Co@Pt supported on porous graphitic carbon (denoted as Pt3Co@Pt/C) is synthesized via a simple thermal method, and further used as an efficient electrocatalyst for oxygen reduction reaction (ORR) in the direct methanol fuel cell. An atomic‐resolution high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) measurement combining with line‐profile analysis reveals that the average thickness of Pt‐shell is around 0.4–0.6 nm, forming an ultrathin catalytic layer. Given its unique geometric and electronic structure, the as‐prepared Pt3Co@Pt/C displays highly enhanced electrocatalytic ORR activity and stability, boosted anti‐methanol poisoning ability with a high onset potential and an exceptional half‐wave potential in 0.1 M HClO4 solution. Impressively, its mass activity (0.71 mA mgPt−1) and specific activity (2.75 mA cmPt−2) for ORR are 3.7‐ and 8.1‐fold higher than those of commercial Pt/C catalyst, respectively. The Pt3Co@Pt/C nanocatalysts show remarkable tolerance against methanol poisoning, evidenced by the in situ Fourier‐transform infrared (FTIR) spectroscopy. This work points out a path for the design of high‐performance nanocatalysts for accelerating the development of clean energy technologies involving ORR. [ABSTRACT FROM AUTHOR]

Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built-in electric field (BEF) strategy to fabricate heterogeneous nickel phosphide-cobalt nanowire arrays grown on carbon fiber paper (Ni 2 P-CoCH/CFP) with large work function difference (ΔΦ) as bifunctional electrocatalysts for overall water splitting. Impressively, Ni 2 P-CoCH/CFP exhibits a remarkable catalytic activity for hydrogen and oxygen evolution reactions to obtain 10 mA cm -2 , respectively. Moreover, the assembled lab-scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis with a 100 % faradic efficiency. Computational calculations combining with experiments reveal the interface-induced electric field effect facilitates asymmetrical charge distributions, thereby regulating the adsorption/desorption of the intermediates during reactions. This work offers an avenue to rationally design high-performance heterogeneous electrocatalysts., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Photoelectrocatalytic (PEC) CO 2 reduction to value-added chemicals is a promising solution to address the energy and environmental issues we face currently. Herein, a unique photocathode Bi@ZFO NTs (Bi and α-Fe 2 O 3 co-modified ZnO nanorod arrays) with high utilization of visible light and sharp-tips effect are successfully prepared using a facile method. Impressively, the performance of Bi@ZFO NTs for PEC CO 2 reduction to HCOOH included small onset potential (-0.53 V vs RHE), Tafel slope (101.2 mV dec -1 ), and a high faraday efficiency of 61.2% at -0.65 V vs RHE as well as favorable stability over 4 h in an aqueous system under visible light illumination. Also, a series of experiments were performed to investigate the origin of its high activity, indicating that the metallic Bi and α-Fe 2 O 3 /ZnO nanojunction should be responsible for the favorable CO 2 adsorption/activation and charge transition/carrier separation, respectively. Density functional theory calculations reveal that the Bi@ZFO NTs could lower the intermediates' energy barrier of HCOO* and HCOOH* to form HCOOH due to the strong interaction of Bi and α-Fe 2 O 3 /ZnO.