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Electrocatalytic dehalogenation technology is a promising approach for the synthesis of chemicals (such as pesticides and pharmaceutical intermediates) and the disposal of halogenated organic pollutants. Compared with the traditional chemical reduction technology, the electrocatalytic reduction dehalogenation method has the advantages of high efficiency, controllable operation, and reduced secondary pollution. This review systematically consolidates the recent advances in the electrocatalytic dehalogenation in the application of organic synthesis and environmental degradation, focusing on the involved mechanisms, and influences factors (e.g., electrocatalysts, solution environment, and reaction conditions) on the performance of electrocatalytic dehalogenation. Furthermore, the latest characterization and analytical methods and the industrial application of electrocatalytic dehalogenation technology are summarized. Lastly, the existing challenges and perspectives are proposed for efficient electrocatalytic dehalogenation. Electrocatalysis is a promising approach for dehalogenation. This review introduces the recent advances of the electrocatalytic dehalogenation technology in the synthesis of chemicals and the disposal of halogenated organic pollutants, focusing on the involved mechanisms, and influences factors, characterization and analytical methods, and the industrial application.

Electrochemical selective dechlorination can be regarded as one of the most promising strategies for generating high-valued chemicals. In the electrochemical dechlorination process of 2-chloro-5-trichloromethylpyridine (TCMP), except the anticipated dechlorination products involving 2-chloro-5-dichloromethylpyridine (DCMP), 2-chloro-5-chloromethylpyridine (CCMP), and 2-chloro-5-methylpyridine (CMP), some unexpected oxygen-incorporated products (6-chloronicotinic acid (CNA) and 6-chloronicotinoyl methyl ester (MCN)) can be obtained. Consequently, understanding the electrochemical dechlorination behavior of TCMP is crucial. Our research revealed that the activated Ag electrodes in halide ion solution exhibit enhanced electrochemical activities for electrochemical dechlorination of TCMP, compared with the pure Ag owing to the increased active specific surface areas and charge transfer. Second, oxygen participation in the reaction is a necessary condition for the formation of oxygen-incorporated products. A 100% selectivity of oxygen-incorporated products can be obtained at the potential of −0.6 V vs Ag/AgCl. Conversely, insufficient oxygen may lead to the potential becoming the determining condition that affects the reaction pathways. A more negative potential (−1.2 V vs Ag/AgCl) is conducive to the formation of dechlorination products with 94.2% conversion and 100% selectivity. This study, for the first time, elucidates the electrocatalyst, atmosphere, and potential-dependent activity and selectivity for the two dechlorination pathways of TCMP.

Bimetallic-sites construction and coordination species tuning are considered as effective strategies to improve electrocatalytic performance of 5-hydroxymethylfurfural (HMF) oxidation. However, it remains a challenging issue to clarify the roles of dual-sites and coordinating anions through optimized electronic structure. Herein, hierarchical NiCo-based sulfide (NiCo–S) nanosheets are reported to disclose the composition-dependent activity at the atomic level. X-ray absorption spectroscopy (XAS) evaluates the tuned electronic configuration. Electrochemical experimental and theoretical results manifest that Ni–Co dual sites synergistically participate in HMF oxidation, where Co sites promote the transformation of the aldehyde (CHO) group to the carboxyl group with the strong diatomic adsorption (O and C atoms) on the CHO group of HMF, while Ni sites speed up the reaction rate of 2,5-furandicarboxylic acid (FDCA) generation. Meanwhile, the coordinating S species also contributes to the formation of strong diatomic adsorption with the CHO group of HMF, and a larger density of state (DOS) of NiCo–S at the Fermi level demonstrates a higher conductivity for carrier transfer compared with NiCo–O. All the above studies confirm the effects of the Ni–Co dual-sites and S coordination on accelerating reactions and lowering energy barriers, thus facilitating the catalytic activity (98.0% selectivity and 97.1% yield for FDCA) with rapid reaction kinetics and low onset potential (1.2 V vs.RHE).

A new class of three-component photocatalyst system is designed with plasmonic AuCu nanoprisms embedded between a porous single crystalline TiO2nanoplate thin film and polyhedral zeolitic imidazolate frameworks (ZIF-8) nanoparticles for enhanced CO2photocatalytic reduction. The ZIF-8 plays a role of CO2capture to enhance the reactant concentration on the catalyst, while the AuCu nanoprisms function mainly as a mediator to improve the charge density at the interfaces and facilitate the charge transfer to the CO2adsorption sites on ZIF-8 for subsequent CO2reduction. The reactant CO2could be not only readily collected on the newly designed catalyst, but also more efficiently converted to CO and CH4. As a result, compared to the reference sample of two-component system of TiO2and ZIF-8 with a CO2conversion rate of 12.5 μmol h−1 g−1, the new three-component photocatalyst exhibited a nearly 7-fold improvement in CO2photocatalytic reduction performance with CO2conversion reaching an outstanding value of 86.9 μmol h−1 g−1, highlighting the importance of rational heterojunction design in facilitating reactant adsorption, charge transfer and reaction processes in photocatalysis.

Realizing efficient charge separation and transfer is a key challenge for solar energy conversion. Here, we proposed the creation of an external electric field (EEF) by molecules interface engineering with silane grafting to form strong positive electricity on surface in semiconductor photocatalyst, driving charge separation and transfer in both bulk and surface. Forced by the EEF, WO3nanoplates anchored silane molecules (WO3-SiH2NH2) for efficient photoelectrochemical (PEC) water oxidation shows 44.8% photocurrent enhancement. Interestingly, the photocurrent onset on WO3-SiH2NH2exhibited a 0.3V negative shift from 0.5 to 0.2 VRHEcompared with pure WO3caused by the change of band edge position. The strategy of creating EEF is proven effective using other semiconductors and opens up a potential application to construct numerous high performance photoelectrodes for water splitting.

•The wind measurement method for two UAV anemometry systems is proposed.•The advantages of low cost and flexibility of the UAV anemometry system can improve the wind measurement efficiency.•At 10D, the wake width was about 2.5 times the turbine diameter, the wake flow was considerably close to the incoming flow.•The Gaussian-shape curve could better describes wind speed distribution on the horizontal plane of the wind turbine wake.•The peak point for the normalized power spectrum of the wake wind was slightly different from that of incoming wind.

Transforming glyoxal to value-added glyoxylic acid (GA) is highly desirable but challenging due to the uncontrollable over-oxidation. In this work, we report on a first demonstration of semi-oxidation of glyoxal with high selectivity (86.5%) and activity on WO3nanoplate photoanode through the photoelectrochemical strategy. The optimization of reactivity was achieved via crystal facet regulation, showing a satisfactory GA production rate of 308.4 mmol m–2h–2, 84.0% faradaic efficiency, and 4.3% total solar-to-glyoxylic acid efficiency on WO3with enriched {200} facets at 1.6 V versus RHE. WO3with a high {200} facet ratio exhibits more efficient electron–hole transfer kinetics, resulting in the facilitated formation of hydroxyl radicals (•OH) and glyoxal radicals. Meanwhile, the theoretical calculation results indicate that the high selectivity and activity come from the strong adsorption ability for glyoxal and the low reaction energy for glyoxal radical generation on the (200) facets of WO3. Moreover, the high energy demand toward oxalic acid production on WO3leads to the exciting semi-oxidation process.