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The reduction degree of TiO2 support is critical to the performances of metal catalysts. In many previous theoretical calculations, only the bridge oxygen vacancy (Ov) was considered as the electron-donating defect on reduced rutile TiO2 (r-TiO2−x) supports. However, titanium adatoms (Tiad.), oxidized titanium islands (Tiad.On), and acid hydroxyls (ObrH) also exist at the metal/support interface. By conducting density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations, we compared r-TiO2−x surfaces with Ov, Tiad., Tiad.On, and ObrH sites loaded with Au nanoparticles (NPs). The results showed the Au NPs were oxygen-phobic but titanium-philic, resulting in wetting of Ov and Tiad. but short contact with Tiad.On and ObrH. The Bader charges of Au NPs (QM) showed a good linear relationship with the ideal number of donating electrons (Ne) from the defective sites (QM = −KeNe + QM,S), demonstrating the intrinsic electron allocation at the interface. The Ov, Tiad., and Tiad.On exhibited similar slopes (Ke), relatively steeper than that of ObrH. That means in the scope of Au NP charge state, the Tiad. and Tiad.On have a close electron-donating ability with Ov, but the ObrH donates relatively fewer electrons. This linear relationship can be extended approximately to other metals. The higher the metal work function, the steeper the Ke for easier electron donation from defective sites. The stronger the metal oxygen affinity, the more positive the intercept (QM,S). That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO2−x, but hard for Cu and Zn in experiment. That provides theoretical guidance for regulating the charge of metal NPs over TiO2−x supports. [ABSTRACT FROM AUTHOR]

• All dispersants considered acted in synergy with resins in peptizing asphaltenes. • Ionic liquid yielded the best dispersing power and the highest self-association. • Significant electron-withdrawing sites were main contributors to dispersing power. • Steric hinderance associated with molecular structure affected dispersing behavior. In confronting the global climate change, reusing waste asphalt materials stands out as a key strategy for the transportation sector to preserve natural resources and reduce the carbon footprint. Recycling additives or rejuvenators are usually required in this practice, especially for boosting the recycling rate. Given the imperative need for a general compositional design principle of rejuvenators, we previously proposed an innovative formulation concept by combining softeners with asphaltene dispersants, and reported that the use of dispersants largely reduced the total quantity of rejuvenators needed and thus would minimize the environmental impacts. The present study is aimed for probing the molecular mechanisms underlying this observation, with additional interest focused on the synergistic effect of the dispersants with resins and also on the impacts due to their self-association. Selection of representative materials consisted of three types of dispersants including an ionic liquid, a phenolic amphiphile, and an ester plasticizer, in combination with an aromatic oil as the softener. Long-time molecular dynamics (MD) simulation was employed to inspect the aggregation of asphaltenes. Quantum chemical (QC) computation was performed to provide insights into the source of different dispersing behaviors. The results indicated that the three dispersants all acted in concert with resins in dispersing asphaltenes. The dispersion characteristics of asphaltenes could be viewed as a net result of the two competing mechanisms of the dispersing capability and self-association of the dispersant used. The ionic liquid exhibited much higher propensity to self-association at increasing concentrations than the phenolic dispersant, and yet the optimum performance was achieved for both when they were added at low dosages. The ester plasticizer showed minimal self-association and yielded improved dispersion with increasing concentrations. In all cases, the dispersing functionality mainly originated from the presence or formation of significant electron-withdrawing sites, collectively due to the highly electronegative cation and anion, hydrogen bonding, and polar groups. Comparison of the dispersing power was also conducted from different perspectives. The findings are expected to provide molecular insights for formulating versatile and more environmentally benign asphalt rejuvenators. [ABSTRACT FROM AUTHOR]

• Innovative introduction of Co element into Na 2 FeP 2 O 7 material using a sol–gel method, as well as the reduction of active particles' size to nano-level and the formation of continuous carbon layer. • Taking advantage of "zero-strain" characteristic. • Enhanced charge/discharge capacity, superb rate capability and ultra-long cycling lifespan with a high capacity retention. • Experimental and theoretical investigation of the effect of Co doping with various measurements, including in-situ/ ex-situ characterizations, FIB-SEM, DFT calculations etc. Na 2 FeP 2 O 7 cathode material exhibits great promise in sodium ion batteries (SIBs), due to its low cost and high structural durability. Nevertheless, the intrinsically poor electronic conductivity and sluggish Na+ diffusion kinetics of Na 2 FeP 2 O 7 hinder its practical application. Herein, a synergistic cooperation of continuous amorphous carbon layer and optimized Co doping strategy is proposed to design high-performance SIB cathode (Co-doped Na 2 FeP 2 O 7 /C) via in-situ sol–gel method, where Co integration significantly enhances both the electronic conductivity and the Na+ diffusion kinetics, as confirmed by the combination of ex/in-situ characterizations and density functional theory calculations. Valuably, the synergy of amorphous carbon layer and appropriate Co doping restrains the structure stress to "zero-strain", Which remains beneficial for 0.10Co-NFO@C to display a high capacity of 96.12 mAh g-1 at 0.05C and a high-rate capacity of 61.75 mAh g-1 at 60C with the capacity retention of 79.9% after 5000 cycles. Moreover, optimized Co-doped Na 2 FeP 2 O 7 /C also shows outstanding cycling performance and rate capability when assembled into full batteries (hard carbon as the anode), demonstrating a reversible capacity of ∼110.9 mAh g-1 at 50 mA g−1, and a respectable capacity retention of 78.0% at 500 mA g−1 for 500 cycles. The strategy inspires new advances towards zero-strained cathode materials for high performance SIBs. [ABSTRACT FROM AUTHOR]