The mechanism of how interfacial wettability impacts the CO2 electroreduction pathways to ethylene and ethanol remains unclear. This paper describes the design and realization of controllable equilibrium of kinetic-controlled *CO and *H via modifying alkanethiols with different alkyl chain lengths to reveal its contribution to ethylene and ethanol pathways. Characterization and simulation reveal that the mass transport of CO2 and H2O is related with interfacial wettability, which may result in the variation of kinetic-controlled *CO and *H ratio, which affects ethylene and ethanol pathways. Through modulating the hydrophilic interface to superhydrophobic interface, the reaction limitation shifts from insufficient supply of kinetic-controlled *CO to that of *H. The ethanol to ethylene ratio can be continuously tailored in a wide range from 0.9 to 1.92, with remarkable Faradaic efficiencies toward ethanol and multi-carbon (C2+) products up to 53.7% and 86.1%, respectively. A C2+ Faradaic efficiency of 80.3% can be achieved with a high C2+ partial current density of 321 mA cm−2, which is among the highest selectivity at such current densities.

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Ultrafine M-phase VO2 nanocrystals with good crystallinity are desirable for highly efficient thermochromic flexible films. Herein, we report an oxygen-controlled hydrothermal method to achieve the one-step preparation of stoichiometric and size-controllable VO2(M) nanoparticles for scaled-up production. The specific ratio of oxygen intake to V ions was first determined to guarantee the acquisition of stoichiometric VO2(M). Then, the hydrothermal conditions were optimized to perform size-controllable growth of VO2(M) nanoparticles. VO2(M) nanoparticles with average particle sizes of 25, 32, 41, and 52 nm were prepared by changing the precursor solution concentration under the determined oxygen intake/V ion ratio. Smaller VO2(M) nanoparticles exhibit better thermochromic performance because a smaller size favors light transmission and promotes blue-shifting of the local surface plasmon resonance. The flexible film fabricated with 25 nm VO2(M) nanoparticles shows an excellent thermochromic performance with a solar modulation efficiency (ΔT sol) of 19.2% and a luminous transmittance (T lum) up to 66.42%. This work proposes a simple and effective hydrothermal process producing size-controllable VO2(M) nanoparticles with low cost and scalable production and demonstrates that the size reduction of VO2(M) nanoparticles is favorable for flexible films to exhibit excellent thermochromic properties.

VO2 is a promising candidate for smart energy-saving windows because of its unique thermochromism but suffers from a high transition temperature of 68 °C and poor thermochromic performance near room temperature. We fabricated a W-VO2/Cs0.32WO3 (CWO) composite flexible film, which shows a low transition temperature of 31.1 °C (W-VO2/CWO = 1:1) and much enhanced near-infrared shielding performance. The optimal W-VO2 + 0.5CWO reaches a desired near-infrared shielding efficiency of 76.34%. A model-house test under simulated solar irradiation further signifies the excellence of the W-VO2 + 0.5CWO composite flexible film under ambient conditions. The robust performance is attributed to the synergetic effects between W-VO2 and Cs0.32WO3, among which the former possesses a low MIT transition temperature and the latter possesses photo-thermal performance.