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fabricated for application over a large area, and applicability in flexible electronics. [1][2][3][4][5][6] It is possible to design high-performance devices by designing photoactive materials that constitute a bulk heterojunction (BHJ), [7][8][9] device engineering, [10][11][12][13] and a combination of these. [14,15] Therefore, this has attention as an area in which commercialization can occur through the application of flexible, wearable, and portable devices, and building-integrated photovoltaics. [4,[16][17][18][19][20] Recently, different methods such as spin coating, [21][22][23] slotdie coating, [24][25][26] and blade coating, [27,28] are being attempted to develop large-area modules with laboratory-to-industrial applications. Among them, slot-die coating can easily control each layer and the related processing factors, such as discharge rate and speed, thus enabling control of thickness and conformation. Therefore, it is the most appropriate coating method to use to produce devices and modules with large areas. [16,29] Krebs and co-workers fabricated flexible OSC modules using a roll-to-roll (R2R) manufacturing process called "ProcessOne." Their flexible OSC modules with power conversion efficiencies (PCEs) of 2-3% demonstrated an energy payback time (EPBT) of 2.02-1.35 years. [30,31] Using Proces-sOne, the BHJ layer and buffer layer were formed using slot-die coating and the Ag back electrode was formed via screen printing; this resulted in the design of OSC modules with inverted structures, which enabled cost-effective production. [32,33] Several particular challenges need to be considered in the manufacturing of this type of OSC modules using an R2R process; these included thermally treating the film [34,35] and ensuring the thermal stability of the substrate [36] the uniformity of the film morphology, [22][23][24] and the evaporation process of the buffer layer and the electrode. [3,25,26,37] The large-area flexible OSC modules have been reported their efficiencies with various materials and coating methods. In flexible unit-cells with small-area, Peng and co-workers recently reported high PCE of 14.06% introducing ternary heterojunction strategy in active area of 0.04 cm 2 . [38] The flexible OSC module based thermally evaporated top electrode reported relatively higher performances. Zhou and co-workers reported tandem structure with PCE of 6.5% in active area of 10.5 cm 2 , also, Ma and co-workers reported ternary structure with PCE of To ensure laboratory-to-industry transfer of next-generation energy harvesting organic solar cells (OSCs), it is necessary to develop flexible OSC modules that can be produced on a continuous roll-to-roll basis and to apply an allsolution process. In this study, nonfullerene acceptors (NFAs)-based donor polymer, SMD2, is newly designed and synthesized to continuously fabricate high-performance flexible OSC modules. Also, multifunctional hole transport layers (HTLs), WO 3 /HTL solar bilayer HTLs, are developed and applied via an all-solution process called "ProcessOne...

For the commercialization of organic solar cells (OSCs), the fabrication of large-area modules via a solution process is important. The fabrication of OSCs via a solution process using a nonfullerene acceptor (NFA)-based photoactive layer is limited by the energetic mismatch and carrier recombination, reducing built-in potential and effective carriers. Herein, for the fabrication of high-performance NFA-based large-area OSCs and modules via a solution process, hybrid hole transport layers (h-HTLs) incorporating WO3 and MoO3 are developed. The high bond energies and electronegativities of W and Mo atoms afford changes in the electronic properties of the h-HTLs, which can allow easy control of the energy levels. The h-HTLs show matching energy levels that are suitable for both deep and low-lying highest occupied molecular orbital energy level systems with a stoichiometrically small amount of oxygen vacancies (forming W6+ and Mo6+ from the W5+ and Mo5+), affording high conductivity and good film forming properties. With the NFA-based photoactive layer, a large-area module fabricated via the all-printing process with an active area over 30 cm2 and a high power conversion efficiency (PCE) of 8.1% is obtained. Furthermore, with the h-HTL, the fabricated semitransparent module exhibits 7.2% of PCE and 22.3% of average visible transmittance with high transparency, indicating applicable various industrial potentials.

Antioxidant agents counter reactive oxygen species (ROS) and can be used in cosmetic and medicinal applications. The goal of this study was to evaluate the antioxidant activity of an Antarctic moss species from King George Island (Antarctica), tentatively designated as KSJ-M5. On the basis of morphological characteristics, KSJ-M5 was identified as Sanionia uncinata (Hedw.) Loeske (Amblystegiaceae). The identification was confirmed by comparing the partial sequence of the ITS (internal transcribed spacer) region with that in GenBank. The antioxidant activity of an ethanol extract of KSJ-M5 was evaluated by analyzing its reducing power, superoxide scavenging activity, ABTS [2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] cation scavenging activity, and DPPH (1,1-diphenyl-2-picrylhydrazyl) free-radical scavenging activity. The reducing power of 1 mg of KSJ-M5 extract was equivalent to 31.9 +/- 0.9 microg (Mean +/- SD, n = 3) of the commercial standard, BHT (butylated hydroxytoluene). IC(50) values of the KSJ-M5 extract for DPPH free-radical scavenging activity, superoxide scavenging activity, and ABTS cation scavenging activity were found as 356 +/- 26.8 microg/mL, 466.2 +/- 43.4 microg/mL, and 181.3 +/- 12.2 microg/mL, respectively. The total phenolic content in 1 mg of KSJM5 extract was equivalent to 12.7 +/- 2.7 microg of pyrocatechol. These results clearly showed that KSJ-M5 could be an important source of natural antioxidant agents for improved medicinal and cosmetic applications.

The COVID-19 pandemic has significantly changed our daily life, especially in the food industry. This study aims to examine the sustainable factors that influence the reuse intention in China’s online-to-offline (O2O) food delivery industry, using “Meituan Waimai” app users as the objects of investigation. Meituan had great success in the initial stage of business due to the rapid urbanization of the major Chinese cities, and thus it is planning to enter the second and third level of cities in China. However, this may not be sustainable because beginner’s luck does not hold unless it is supported by sustainable governance. To evaluate the online and offline governance of O2O business, we used five service quality factors (convenience, safety, economy, accuracy, and speed) in a structural equation model. Customer satisfaction and reuse intention are used as mediating and dependent variables, respectively. The main findings are as follows. First, among the service characteristics, economy and speed factors did not perfectly mediate satisfaction, implying that the initial stage of success may not be sustainable. O2O service providers in China should put more effort into customizing economic incentives as well as making an appropriate impression regarding the delivery speed. Second, satisfaction is fully supported by other factors, implying that O2O service providers should take into account feedback from the people in the market and consumers.

Two strategies were investigated to improve the efficiency of organic solar cells (OSCs) with the aim of controlling the interfacial resistance in the devices: the use of a ternary active layer and the introduction of conjugated polymers. The ternary active layer was formed by introducing PC 71 BM between a high-performance non-fullerene photoactive material P(Cl−Cl) (BDD = 0.2) and the IT-4F-based binary active layer, thereby reducing the interfacial resistance between the donor and acceptor via vertical phase separation. Furthermore, the introduction of the conjugated polymer PFN-Br created a well-dispersed separation attributable to enhancement of the interfacial contact with the active layer and simultaneous reduction of the interfacial resistance. Consequently, the synergetic effect of the ternary active layer and PFN-Br enhanced the short-circuit current density (J SC ) and fill factor (FF) to realize a power conversion efficiency (PCE) of 13.2%.

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With the advent of the smart factory and the Internet of Things (IoT) sensors, organic photovoltaics (OPVs) gained attention because of their ability to provide indoor power generation as an off-grid power supply. To satisfy these applications, OPVs must be capable of power generation in both outdoor and indoor at the same time for developing environmentally independent devices. For high performances in indoor irradiation, a strategy that maximizes photon utilization is essential. In this study, graphene quantum dots (GQDs), which have unique emitting properties, are introduced into a ZnO layer for efficient photon utilization of nonfullerene-based OPVs under indoor irradiation. GQDs exhibit high absorption properties in the 350–550 nm region and strong emission properties in the visible region due to down-conversion from lattice vibration. Using these properties, GQDs provide directional photon energy transfer to the bulk-heterojunction (BHJ) layer because the optical properties overlap. Additionally, the GQD-doped ZnO layer enhances shunt resistance (R Sh) and forms good interfacial contact with the BHJ layer that results in increased carrier dissociation and transportation. Consequently, the fabricated device based on P­(Cl-Cl)­(BDD = 0.2) and IT-4F introduces GQDs exhibiting a maximum power conversion efficiency (PCE) of 14.0% with a superior enhanced short circuit current density (J SC) and fill factor (FF). Furthermore, the fabricated device exhibited high PCEs of 19.6 and 17.2% under 1000 and 200 lux indoor irradiation of light emitting diode (LED) lamps, respectively.