Bioinspired Gas Manipulation for Regulating Multiphase Interactions in Electrochemistry.

The manipulation of gas in multiphase interactions plays a crucial role in various electrochemical processes. Inspired by nature, researchers have explored bioinspired strategies for regulating these interactions, leading to remarkable advancements in design, mechanism, and applications. This paper provides a comprehensive overview of bioinspired gas manipulation in electrochemistry. It traces the evolution of gas manipulation in gas-involving electrochemical reactions, highlighting the key milestones and breakthroughs achieved thus far. The paper then delves into the design principles and underlying mechanisms of superaerophobic and (super)aerophilic electrodes, as well as asymmetric electrodes. Furthermore, the applications of bioinspired gas manipulation in hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), and other gas-involving electrochemical reactions are summarized. The promising prospects and future directions in advancing multiphase interactions through gas manipulation are also discussed.

Novel catalyst-free activation of chlorine by visible light for micropollutant abatement.

This study systematically investigated the direct activation of chlorine by visible light emitting diode (Vis-LED). Vis-LED could effectively activate chlorine to degrade micropollutants with degradation efficiency and pseudo-first-order degradation rate constant range of 64.3-100 % and 0.0340-0.195 min-1, respectively. Quenching experiments and modeling results suggested that reactive chlorine species (RCS, including ClO•, Cl2•-, and Cl•) and hydroxyl radical (•OH) were involved in the degradation of atenolol (ATL). The contribution ratio of ClO•, free available chlorine, Cl•, Cl2•-, and •OH to ATL degradation were 58.7 %, 17.4 %, 15.6 %, 1.8 %, and 5.9 %, respectively, in Vis-LED448/chlorine process. Moreover, the innate quantum yields of HClO and ClO- decreased from 0.229 and 0.0206 to 0.0489 and 0.0109 mol·Einstein-1, respectively, as the wavelength increased from 448 to 513 nm, leading to a decrease in ATL degradation, which was consistent with the model results. Experimental and modeling results have confirmed that ATL degradation decreased when pH increased from 4.0 to 9.0. Cl- had little effect on the degradation of ATL, while HA and HCO3- affected ATL degradation by scavenging reactive species and/or shielding effect. The concentration of disinfection by-products decreased with the increase of wavelength and pH. In summary, Vis-LED/chlorine is an efficient water treatment process even without a catalyst.

A Multi-Bioinspired Dual-Gradient Electrode for Microbubble Manipulation toward Controllable Water Splitting.

Clean energy generated from total water splitting is expected to be an affordable, sustainable, and reliable resource but it remains a challenge to gain pure fuel with a controllable pathway. Here, a simple and economical strategy that enables in situ separation of H2 /O2 product by manipulating the generated gas phases with the aid of multi-bioinspired electrodes is proposed. This versatile electrode is based on a Janus asymmetric foam with dual gradients, i.e., the wettability gradient promotes the one-way gas penetration and the geometry gradient boosts the spontaneous on-surface transport in the horizontal direction, which cooperatively facilitates self-driven 3D bubble transport in an aqueous environment. Benefitting from the 3D bionic electrode, the limited distance between the cathode and the anode can be reduced to 1 mm, and the corresponding current density is enhanced 1.5 times as compared with the common condition. This Janus triangular electrode with dual directionality elucidates 3D smart bubble manipulation during overall water splitting and should offer a great opportunity to develop advanced electrochemical processes toward complicated environments such as confined space and zero gravity.

[Study on temperature dependence of ultraviolet absorption cross sections of ammonia].

The present paper reports the study of the effects of temperature on the absorption cross-sections of ammonia in spectral region of 200-220 nm. By using a grating monochromator with high resolution, deuterium lamp, closed gas sample cell and gas compounding device, the photoabsorption cross sections of ammonia were measured at temperatures ranging from 308 to 397 K. The absorption spectrum of NH3 consists of discrete bands superimposed on a continuous base. Results indicated that the cross sections at the peaks of the discrete bands decreased with the increase in temperature, which corresponded to the decrease in the population of vibrational and rotational transitions from the base level to higher excitation levels. The absorption cross section peaks decreased when the temperature increased from 308 to 397 K, with a relative drop of 46%. Another distinctive feature of ammonia absorption spectra in the above spectral regions was the quasiperiodic structure of absorption peaks, whose equal wavelength interval was 4 nm. Besides, absorption peak positions were not changed. Continuous absorption cross section decreased with the increase in temperature, and the variation gradient gradually decreased with wavelength red shift. A compensation calculation for temperature should be carried out in on-line measurement of concentration because of the greater variation rate of absorption cross sections of ammonia.