The electrochemical production of hydrogen peroxide (H 2 O 2 ) by 2-electron oxygen reduction reaction (ORR) is an attractive alternative to the present complex anthraquinone process. The objective of this paper is to provide a state-of-the-arts review of the most important aspects of this process. First, recent advances in H 2 O 2 production are reviewed and the advantages of H 2 O 2 electrogeneration via 2-electron ORR are highlighted. Second, the selectivity of the ORR pathway towards H 2 O 2 formation as well as the development process of H 2 O 2 production are presented. The cathode characteristics are the decisive factors of H 2 O 2 production. Thus the focus is shifted to the introduction of commonly used carbon cathodes and their modification methods, including the introduction of other active carbon materials, hetero-atoms doping (i.e., O, N, F, B, and P) and decoration with metal oxides. Cathode stability is evaluated due to its significance for long-term application. Effects of various operational parameters, such as electrode potential/current density, supporting electrolyte, electrolyte pH, temperature, dissolved oxygen, and current mode on H 2 O 2 production are then discussed. Additionally, the environmental application of electrogenerated H 2 O 2 on aqueous and gaseous contaminants removal, including dyes, pesticides, herbicides, phenolic compounds, drugs, VOCs, SO 2 , NO, and Hg 0 , are described. Finally, a brief conclusion about the recent progress achieved in H 2 O 2 electrogeneration via 2-electron ORR and an outlook on future research challenges are proposed.

A composite electrode composed of reduced graphene oxide‐graphite felt (rGO‐GF) with excellent electrocatalytic redox reversibility toward V2+/V3+ and VO2+/VO2+ redox couples in vanadium batteries was fabricated by a facile hydrothermal method. Compared with the pristine graphite felt (GF) electrode, the rGO‐GF composite electrode possesses abundant oxygen functional groups, high electron conductivity, and outstanding stability. Its corresponding energy efficiency and discharge capacity are significantly increased by 20% and 300%, respectively, at a high current density of 150 mA cm−2. Moreover, a discharge capacity of 20 A h L−1 is obtained with a higher voltage efficiency (74.5%) and energy efficiency (72.0%), even at a large current density of 200 mA cm−2. The prepared rGO‐GF composite electrode holds great promise as a high‐performance electrode for vanadium redox flow battery (VRFB).

Potential dependent electric double layer (EDL) structure of ionic liquids on a polycrystalline Pt electrode has been studied by in-situ IR-visible sum frequency generation (SFG) spectroscopy and differential capacitance measurements. Within the electrochemical window (EW), potential dependent adsorption/desorption processes of the ions have been monitored. Both SFG and capacitance results indicate that significant hysteresis occurs during the adsorption/desorption processes on the Pt surface, while the EDL structure is highly reversible at the potential close to the limit of the EW. The unique hysteresis effect for ionic liquids on electrode surface should be seriously considered in electrochemical applications of ionic liquids.

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Anode materials with high capacity for aqueous rechargeable lithium batteries (ARLBs) are very rarely reported. Here we found that a dual core-shell structured MWCNTs@S@PPy nanocomposite prepared by us shows excellent electrochemical performance. Its initial discharge capacity in a saturated LiAc aqueous electrolyte is very high, which is up to 481 mA h g based on the weight of the composite and 879 mA h g based on the sulfur content. It shows excellent rate capability. When nanotube LiMnO is used as a cathode, the assembled ARLB can deliver an energy density of 110 Wh kg based on two electrodes and show excellent cycling. These results show great promise for the practical application of ARLBs.

promising and environmentally friendly oxidant in advanced oxidation processes (AOPs). Besides, hydrogen peroxide received great attention in fuel cell as well, in which hydrogen still plays an important role. But the low volumetric energy density makes the storage of hydrogen a difficult issue. H 2 O 2 possesses a high energy density and oxidation potential [13] in full pH range (E 0 = 1.763 V at pH = 0, E 0 = 0.878 V at pH 14), [1] which enables it an ideal energy carrier alternative. [11] With a compounded increase of 6%, [14] the annual production of H 2 O 2 had reached 5.5 million tons in 2015. [1] At present, three main categories were conducted to produce H 2 O 2 : direct H 2 O 2 synthesis from H 2 and O 2 , [15] anthraquinone oxidation process (AO-process), [12] and oxygen electroreduction. [16][17] More than 95% of H 2 O 2 were synthesized by AO-process, involving hydrogenation and oxidation of the anthraquinone molecule over Ni or Pd catalysts in organic solvents. [14] However, AO-process is facing some challenges: 1) Low sustainability. The combustible and explosive substances used in AO-process, such as heavy aromatics, trioctyl phosphate, are not environmentally friendly, which brings a negative influence on the sustainability of the AO-process; 2) Transportation insecurity. The high concentration of H 2 O 2 has the potential to explode when flammable materials exist, which brings safety problems to transportation; 3) Exorbitant additional cost. Ahead of being transported, H 2 O 2 has to be concentrated up to 70 wt% with impurity separation [18] and requires acid promoter stabilizer, [14] causing the increase of extra cost. All these make AO-process not the best choice for low cost and distributed H 2 O 2 production.Comparatively, two-electron oxygen reduction reaction (ORR) provides an economic, efficient, and nonhazardous alternative process, achieving the in situ H 2 O 2 production under mild conditions. [1] Furthermore, ORR process could be coupled with renewable energy sources [18] and fuel cell, [19] recovering the energy released ( f 0 ∆G , 120 KJ mol −1 ). [20,21] For instance, solar energy can be directly used as an energy source to produce H 2 O 2 through photoelectric catalysis. [22] In brief, H 2 O 2 production via two-electron oxygen electro-reduction has emerged as a promising candidate to address the demand for distributed energy.Hydrogen peroxide (H 2 O 2 ) is one of the 100 most paramount chemicals in the world, which has been widely used in industrial synthesis, pulp and bleaching, semiconductor cleaning, medical sterilizing, environmental treatments, and energy storage. Among various H 2 O 2 production methods, anthraquinone process has intrinsic drawbacks such as energy-intensive and environmental pollution while 2-electron oxygen reduction reaction (ORR) provides an economic, efficient, and nonhazardous alternative process to realize the in situ production of H 2 O 2 instead. Recently, heteroatom-doped carbon electrocatalysts, especially the nitrogen-doped ones, receive special a...

The development of a three-dimensionally flexible, large-surface area, high-conductivity electrode is important to improve the low conductivity and utilization of active materials and restrict the shuttle of long-chain polysulfides in Li-polysulfide batteries. Herein, we constructed an integrated three-dimensional carbon nanotube forest/carbon cloth electrode with heteroatom doping and high electrical conductivity. The as-constructed electrode provides strong trapping on the polysulfide species and fast charge transfer. Therefore, the Li-polysulfide batteries with as-constructed electrodes achieved high specific capacities of ∼1200 and ∼800 mA h g at 0.1 and 1 C, respectively. After 300 cycles at 0.5 C, a specific capacity of 623 mA h g was retained.

With the rapid development of online shopping and traditional physical store shopping interweaving to form different shopping situations, customer experience has gradually become the main source of retailers’ sustainable competitive advantage through differentiation. Retailers need to continuously improve customer experience in different shopping situations to maintain long-term sustainable customer satisfaction and achieve sustainability. The study aims to examine what kind of shopping situations will influence customer experience and customer satisfaction. A total of 288 questionnaires were collected from two different shopping situations (146 questionnaires from physical stores were collected in five cities in China and 142 online questionnaires were collected from 21 provinces in China), and multiple regression analysis was adopted to test the hypotheses. As a result, we found that customer experience with staff service, shopping environment, and shopping procedure has a positive influence on customer satisfaction. Different shopping situations significantly moderate the relationships among customer experience with the shopping environment, product experience, and customer satisfaction but rarely influence customer experience with staff service and service procedures. Finally, gender significantly moderates the relationship between customer experience and customer satisfaction in different shopping situations. This study theoretically reveals the relationship between customer experience and satisfaction in different shopping situations and provides practical suggestions for retailers to form differentiated sustainable competitive advantage through customer experience management.