White spot lesions (WSLs), a side effect of orthodontic treatment, can result in reversible and unaesthetic results. Graphene oxide (GO) with a bioactive glass (BAG) mixture (BAG@GO) was added to Low-Viscosity Transbond XT (LV) in a ratio of 1, 3, and 5%. The composite’s characterization and its physical and biological properties were verified with scanning electron microscopy (SEM) and X-ray diffraction (XRD); its microhardness, shear bond strength (SBS), cell viability, and adhesive remnant index (ARI) were also assessed. Efficiency in reducing WSL was evaluated using antibacterial activity of S. mutans. Anti-demineralization was analyzed using a cycle of the acid-base solution. Adhesives with 3 wt.% or 5 wt.% of BAG@GO showed significant increase in microhardness compared with LV. The sample and LV groups showed no significant differences in SBS or ARI. The cell viability test confirmed that none of the sample groups showed higher toxicity compared to the LV group. Antibacterial activity was higher in the 48-h group than in the 24 h group; the 48 h test showed that BAG@GO had a high antibacterial effect, which was more pronounced in 5 wt.% of BAG@GO. Anti-demineralization effect was higher in the BAG@GO-group than in the LV-group; the higher the BAG@GO concentration, the higher the anti-demineralization effect.

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LIBs) are desirable to significantly increase to fulfill the growing demand for long distance per each charge. For this reason, next generation batteries such as Li-S, Li-O 2 , and Li-metal with exceptional energies have been attracted much attention as potential candidates due to their outstanding performances. [1][2][3][4][5] However, unfortunately, as a substantial amount of electrochemical energy should be stored in a confined volume, these systems are thermodynamically unstable, which could be a risk for safety incidents.In an attempt to overcome these drawbacks, the all-solid-state batteries (ASSBs) with all-solidified components are now considered as a promising next-generation technology beyond state-of-the-art LIBs. [6] The fascinating features of the ASSBs lie in the opportunity of enhancing energy density and surmounting the intrinsic shortcomings of conventional liquid-based batteries, such as electrolyte leakage, flammability, narrow voltage window, and low lithium ion transport number. In other words, the ASSBs are promising systems due to nonvolatile, nonexplosive, and stability up to ≈6.0 V versus Li/Li + . [6][7][8][9][10] In particular, if lithium metal can be employed as an anode material and interfacial stability can be improved, [11,12] it can be possible to achieve high energy and power density. These extraordinary properties of the ASSBs have extensively stimulated scientific and industry communities to the ASSB's research.In order to achieve superior electrochemical performances of the ASSBs, not only improving interfacial stability during the cycling, but balancing both ionic and electronic conductivities of composites is of crucial importance. For instance, while the electronic pathways appear to be more important for the high energy density ASSBs operating at relatively low current density, the sufficient ion transport is a more critical factor at high rate operations for the high power density ASSBs, [13,14] although the cell performances are relatively related to diverse factors such as the operating pressure/temperature, particle size, and composition in the electrode. In terms of enhancement of the ionic conductivity, extensive efforts for developing solid electrolyte (SE) with high ionic conductivity have been conducted for past few decades. Among diverse candidates, much attention has been focused on the sulfide-based SE including Li 10 GeP 2 S 12 (LGPS), [7,15] β-Li 3 PS 4 , [16] Li 7 P 3 S 11 , [17] Li 2 S-P 2 S 5 , [18] and argyrodite All-solid-state batteries (ASSBs) have lately received enormous attention for electric vehicle applications because of their exceptional stability by engaging all-solidified cell components. However, there are many formidable hurdles such as low ionic conductivity, interface instability, and difficulty in the manufacturing process, for its practical use. Recently, carbon, one of the representative conducting agents, turns out to largely participate in side reactions with the solid electrolyte, which finally leads to the formation of insulating sid...

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Hole transport materials (HTMs) play essential roles in achieving high photovoltaic performance and long‐term stability in the n–i–p structure of perovskite solar cell (PSC) devices. Recently, dopant‐free polymeric materials as HTMs in PSCs have attracted considerable attention owing to high carrier mobility and excellent hydrophobicity. However, achieving similar efficiencies to those of doped small molecule HTMs such as Spiro‐OMeTAD is a big challenge. Herein, a thienothiophene π‐bridge is selected as a stabilizer and energy level regulator incorporated into a donor–acceptor‐type HTM to synthesize a new polymer, Nap‐SiBTA. The incorporation of the thienothiophene group improves the thermal stability and favors the high planarity and face‐on orientation, promoting high charge carrier mobility and tunable optical band gap. Finally, the dopant‐free polymer Nap‐SiBTA‐based PSC achieves an excellent power conversion efficiency (PCE) of 23.07% with a high fill factor of 80.85%. To the best of the authors’ knowledge, this is one of the best efficiencies in dopant‐free HTM PSCs. Moreover, the unencapsulated device retains 93% of its initial PCE after 1000 h owing to the excellent hydrophobicity of Nap‐SiBTA. This work provides a general and practical method to design dopant‐free HTMs for the high efficiency and long‐term stability of PSCs.