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Two major issues are currently hindering the clinical practice of titanium dental implants for the lack of biological activities: immediate/early loading risks and peri-implantitis. To solve these issues, it is urgent to develop multifunctional implants modified with effective osteogenic and antibacterial properties. Zinc oxide nanoparticles (ZnO NPs) possess superior antibacterial activity; however, they can rapidly release Zn2+, causing cytotoxicity. In this study, a potential dental implant modification was creatively developed as ZnO nanoparticle-loaded mesoporous TiO2 coatings (nZnO/MTC-Ti) via the evaporation-induced self-assembly method (EISA) and one-step spin coating. The mesoporous TiO2 coatings (MTCs) regulated the synthesis and loading of ZnO NPs inside the nanosized pores. The synergistic effects of MTC and ZnO NPs on nZnO/MTC-Ti not only controlled the long-term steady-state release of Zn2+ but also optimized the charge distribution on the surface. Therefore, the cytotoxicity of ZnO NPs was resolved without triggering excessive reactive oxygen species (ROS). The increased extracellular Zn2+ further promoted a favorable intracellular zinc ion microenvironment through the modulation of zinc transporters (ZIP1 and ZnT1). Owing to that, the adhesion, proliferation, and osteogenic activity of bone mesenchymal stem cells (BMSCs) were improved. Additionally, nZnO/MTC-Ti inhibited the proliferation of oral pathogens (Pg and Aa) by inducing bacterial ROS production. For in vivo experiments, different implants were implanted into the alveolar fossa of Sprague–Dawley rats immediately after tooth extraction. The nZnO/MTC-Ti implants were found to possess a higher capability for enhancing bone regeneration, antibiosis, and osseointegration in vivo. These findings suggested the outstanding performance of nZnO/MTC-Ti implants in accelerating osseointegration and inhibiting bacterial infection, indicating a huge potential for solving immediate/early loading risks and peri-implantitis of dental implants.

Sodium metal batteries are ideal candidates for next-generation grid-level energy storage systems. However, severe obstacles pertain with regard to the usage of metallic Na, including poor processability, dendrite growth, and violent side reactions. Herein, we design a “carbon in metal” anode (denoted as CiM) via a facile method by rolling a controllable amount of mesoporous carbon powder into the Na metal. The as-designed composite anode is endowed with dramatically lowered stickiness and increased hardness (3 times higher than that of pure Na metal) and strength along with improved processability, which can be fabricated into foils with varied patterns and limited thickness (down to 100 μm). Besides, nitrogen-doped mesoporous carbon, which can increase the sodiophilicity, is applied to fabricate N-doped carbon in the metal anode (denoted as N-CiM), which can effectively facilitate the diffusion of Na+ ions and decrease the depositing overpotential, consequently homogenizing the Na+-ion flow and rendering a dense and flat Na deposition. Therefore, the N-CiM anode offers enhanced cycling stability for 800 h at 1 mAh cm–2 in symmetric cells and 1000 cycles with a high average Coulomb efficiency (CE) (99.8%) in full cells based on the conventional carbonate electrolyte.