Deep eutectic solvents (DESs) have emerged as promising alternative candidates for CO2 capture in recent years. In this work, several novel DESs were firstly prepared to enhance CO2 absorption. Structural and physical properties of DESs were investigated, as well as their absorption performance of CO2. A distinct depression in the melting point up to 80 K of DESs was observed compared with that of BMIMCl. The observed red shifts of the C2H group in an imidazolium ring and its chemical shifts downfield in NMR spectra are indicative of a hydrogen bond interaction between BMIMCl and MEA. In particular, CO2 uptake in MEA : ILs (4 : 1) at room temperature and atmospheric pressure is up to 21.4 wt%, which is higher than that of 30 wt% MEA (13%). A hydrogen bond related mechanism was proposed in which ILs act as a medium to improve CO2 uptake through hydrogen bonds. Finally, the firstly reported overall heat of CO2 absorption is slightly higher than that of 30 wt% MEA, implying that the hydrogen bonds of DESs contribute to the overall heat of CO2 absorption. This study reveals that the heat of CO2 absorption can be tailored by the proper molar ratio of MEA and ILs.

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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Bi 2 Te 3 thin films were electrodeposited on silicon substrate with a epitaxial seed layer from acidic aqueous solutions at room temperature. The seed layer optimized the charge transfer in the electrodeposition process and reduced the lattice mismatch between the thin film and the substrate, leading to the Bi 2 Te 3 thin films with uniform structure and highly crystallographically texture. By changing the substrate from doped to intrinsic silicon, we obtained the Bi 2 Te 3 thin films with (00L) preferential orientation which is different from previously reported (015) or (110)-oriented thin films prepared by ECD. The (00L)-oriented thin film showed a more compact structure with lower roughness and an improved thermoelectric performance. The electrical conductivity increased by about 72% compared with the (110)-oriented thin film in our system. Simultaneously, the Seebeck coefficient was comparable, indicating the improvement of power factors by ∼45%. We also altered the thickness of the seed layer from 40 nm to 20 nm and found that both the electrical conductivity and Seebeck coefficient decreased due to the insufficient charge transfer in the electrodeposition process.

A novel reconfigurable microwave photonic (MWP) radar has been proposed and experimentally demonstrated. At a transmitting end, a microwave signal with a large bandwidth and ultra-low phase noise is generated by a Fourier domain mode locking optoelectronic oscillator. At a receiving end, photonics-based de-chirp processing is implemented by phase-modulating light waves in a dual-drive Mach-Zehnder modulator and mixing the modulated light waves at a photodetector. Without the requirement of external RF sources, the developed photonics-assisted programmable radar is capable of generating and processing microwave signals with adjustable format, bandwidth and central frequency. The proposed radar working from X to Ku band with an instantaneous bandwidth of 2 GHz is demonstrated. The reconfiguration of the radar is theoretically analyzed. The tunability of radar bandwidth and central frequency is investigated. Microwave imaging of a pair of trihedral corner reflectors based on the developed MWP radar is achieved.