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Plastic pollution, an increasingly serious global problem, can be addressed through the full lifecycle management of plastics, including plastics recycling as one of the most promising approaches. System design, catalyst development, and product separation are the keys in improving the economics of electrocatalytic plastics recycling. Here, a membrane‐free co‐production system was devised to produce succinic acid (SA) at both anode and cathode respectively by the co‐electrolysis of polybutylene succinate (PBS) waste plastics and biomass‐derived maleic acid (MA) for the first time. To this end, Cr3+‐Ni(OH)2 electrocatalyst featuring much enhanced 1,4‐butanediol (BDO) oxidation reaction (BOR) activity has been synthesized and the role of doped Cr has been revealed as an "electron puller" to accelerate the rate‐determining step (RDS) in the Ni2+/Ni3+ cycling. Impressively, an extra‐high SA production rate of 3.02 g h−1 and ultra‐high apparent Faraday efficiency towards SA (FEapparent=181.5 %) have been obtained. A carbon dioxide‐assisted sequential precipitation approach has been developed to produce high‐purity SA and byproduct NaHCO3 solids. Preliminary techno‐economic analysis demonstrates that the reported system is economically profitable and promising for future industrial applications. [ABSTRACT FROM AUTHOR]

The local acidity at the anode surface during electrolysis is apparently stronger than that in bulk electrolyte due to the deprotonation from the reactant, which leads to the deteriorated electrocatalytic performances and product distributions. Here, an anode‐electrolyte interfacial acidity regulation strategy has been proposed to inhibit local acidification at the surface of anode and enhance the electrocatalytic activity and selectivity of anodic reactions. As a proof of the concept, CeO2‐x Lewis acid component has been employed as a supporter to load Au nanoparticles to accelerate the diffusion and enrichment of OH− toward the anode surface, so as to accelerate the electrocatalytic alcohol oxidation reaction. As the result, Au/CeO2‐x exhibits much enhanced lactic acid selectivity of 81 % and electrochemical activity of 693 mA⋅cm−2 current density in glycerol oxidation reaction compared to pure Au. Mechanism investigation reveals that the introduced Lewis acid promotes the mass transport and concentration of OH− on the anode surface, thus promoting the generation of lactic acid through the simultaneous enhancements of Faradaic and non‐Faradaic processes. Attractively, the proposed strategy can be used for the electro‐oxidation performance enhancements of a variety of alcohols, which thereby provides a new perspective for efficient alcohol electro‐oxidations and the corresponding electrocatalyst design. [ABSTRACT FROM AUTHOR]

During the electrocatalytic NO3− reduction reaction (NO3−RR) under neutral condition, the activation of H2O to generate H* and the inhibition of inter‐H* species binding, are critically important but remain challenging for suppressing the non‐desirable hydrogen evolution reaction (HER). Here, a Mn‐doped Co(OH)2 (named as Mn‐Co(OH)2) has been synthesized by in situ reconstruction in the electrolyte, which is able to dissociate H2O molecules but inhibits the binding of H* species between each other owing to the increased interatomic spacing by the Mn‐doping. The Mn‐Co(OH)2 electrocatalyst offers a faradaic efficiency (FE) of as high as 98.9±1.7% at −0.6 V vs. the reversible hydrogen electrode (RHE) and an energy efficiency (EE) of 49.90±1.03% for NH3 production by NO3−RR, which are among the highest of the recently reported state‐of‐the‐art catalysts in neutral electrolyte. Moreover, negligible degradation at −200 mA cm−2 has been found for at least 500 h, which is the longest catalytic durations ever reported. This work paves a novel approach for the design and synthesis of efficient NO3−RR electrocatalysts. [ABSTRACT FROM AUTHOR]

We report herein an electrocatalytic CO2 reduction‐coupled sulfion oxidation system for the co‐productions of valuable formate and sulfur at much enhanced atom utilization. Specifically, an organic ligand‐assisted two‐step reconstruction approach has been developed to fabricate the highly dispersed p‐Bi nanosheets (p‐Bi NSs) for cathodic CO2 reduction reaction (CO2RR), and meanwhile porous Co−S nanosheets (Co−S NSs) was applied for anodic sulfion oxidation reaction (SOR). Significantly high Faradaic Efficiencies of about 90 % for formate production by CO2RR in a wide potential range from −0.6 V to −1.1 V, and excellent SOR performances including an ultra‐low onset potential of about 0.2 V and recycle capacity of S2− in the 0.1 M and 0.5 M S2− solutions, have been simultaneously achieved. In the meantime, both the structure transformation of the catalysts and the reaction pathways are explored and discussed in detail. A two‐electrode CO2RR||SOR electrolyzer equipped with above electrocatalysts has been established, which features as low as about 1.5 V to run the electrolyzer at 100 mA cm−2, manifesting extremely lowered electricity consumption in comparison to conventional CO2RR system. Moreover, a sulfur separation approach has been proposed by using CO2, which is efficient, environmentally friendly and cost effective with value‐added NaHCO3 be obtained as the byproduct. [ABSTRACT FROM AUTHOR]

Electricity generation and chemical productions are both critically important for the sustainable development of modern civilization. Here, a novel bifunctional Zn‐organic battery has been established for the concurrent enhanced electricity output and semi‐hydrogenations of a series of biomass aldehyderivatives, for the high value‐added chemical syntheses. Among them, the typical Zn‐furfural (FF) battery equipped with Cu foil‐supported edge‐enriched Cu nanosheets as cathodic electrocatalyst (Cu NS/Cu foil), provides a maximum current density and power density of 14.6 mA cm−2 and 2.00 mW cm−2, respectively, and in the meantime, produces high value product, furfural alcohol (FAL). The Cu NS/Cu foil catalyst exhibits excellent electrocatalytic performance of ≈93.5 % conversion ratio and ≈93.1 % selectivity for FF semi‐hydrogenation at a low potential of ‐1.1 V vs. Ag/AgCl by using H2O as H source, and shows impressive performance for various biomass aldehyderivatives semi‐hydrogenation. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogen production under acidic conditions is of great importance for industrialization in comparison to that in alkaline media, which, unfortunately, still remains challenging due to the lack of earth‐abundant, cost‐effective and highly active anodic electrocatalysts that can be used durably under strongly acidic conditions. Here we report an unexpected finding that manganese oxide, a kind of common non‐noble catalysts easily soluble in acidic solutions, can be applied as a highly efficient and extremely durable anodic electrocatalyst for hydrogen production from an acidic aqueous solution of alcohols. Particularly in a glycerol solution, a potential of as low as 1.36 V (vs. RHE) is needed at 10 mA cm−2, which is 270 mV lower than that of oxygen evolution reaction (OER), to oxidize glycerol into value‐added chemicals such as formic acid, without oxygen production. To our surprise, the manganese oxide exhibits extremely high stability for electrocatalytic hydrogen production in coupling with glycerol oxidation for longer than 865 hours compared to shorter than 10 h for OER. Moreover, the effect of the addition of glycerol on the electrochemical durability has been probed via in situ Raman spectroscopic analysis and density functional theory (DFT) calculations. This work demonstrates that acid‐unstable metal oxide electrocatalysts can be used robustly in acidic media under the presence of certain substances for electrochemical purposes, such as hydrogen production. [ABSTRACT FROM AUTHOR]

H2 production via water electrolysis is of great significance in clean energy production, which, however, suffers from the sluggish kinetics of the anodic oxygen evolution reaction (OER). Moreover, the anode product, O2, which is of rather low value, may lead to dangerous explosions and the generation of membrane‐degrading reactive oxygen species. Herein, to address these issues of electrocatalytic H2 production, we summarize the most recent advances in three stages based on the benefit increments and various electron donation routes, which are: 1) electron donation by traditional OER: developing efficient catalysts for water oxidation to promote H2 production; 2) electron donation by the oxidation of sacrificial agents: using sacrificial agents to assist H2 production; 3) electron donation by electrosynthesis reaction: achieving electrosynthesis in parallel with cathodic H2 production. Present challenges and related prospects will also be discussed, hopefully to benefit the further progress of electrocatalytic H2 generation. [ABSTRACT FROM AUTHOR]

The electrochemical conversion of carbon dioxide into energy‐carrying compounds or value‐added chemicals is of great significance for diminishing the greenhouse effect and the efficient utilization of carbon‐dioxide emissions, but it suffers from the kinetically sluggish anodic oxygen evolution reaction (OER) and its less value‐added production of O2. We report a general strategy for efficient formic‐acid synthesis by a concurrent cathodic CO2 reduction and anodic partial methanol‐oxidation reaction (MOR) using mesoporous SnO2 grown on carbon cloth (mSnO2/CC) and CuO nanosheets grown on copper foam (CuONS/CF) as cathodic and anodic catalysts, respectively. Anodic CuONS/CF enables an extremely lowered potential of 1.47 V vs. RHE (100 mA cm−2), featuring a significantly enhanced electro‐activity in comparison to the OER. The cathodic mSnO2/CC shows a rather high Faraday efficiency of 81 % at 0.7 V vs. RHE for formic‐acid production from CO2. The established electrolyzer equipped with CuONS/CF at the anode and mSnO2/CC at the cathode requires a considerably low cell voltage of 0.93 V at 10 mA cm−2 for formic‐acid production at both sides. [ABSTRACT FROM AUTHOR]

Hierarchically porous zeolites have been widely explored for catalytic applications owing to their high specific surface area, large pore volume, favorable mass transfer capability and abundant acidic sites. Herein we report the facile synthesis of Ni‐doped hierarchically Beta zeolite (Ni−H‐beta) via one‐pot hydrothermal method, in which Ni is uniformly doped into the zeolite crystalline skeleton in the form of Ni3+ without any nickel oxides being found. The prepared Ni−H‐beta zeolite shows high performance towards the electrocatalytic methanol oxidation reaction (MOR) with a high current density of 1450 A g−1 at 1.65 V vs RHE, which is higher than most non‐precious MOR electrocatalysts. More importantly, the electrochemical MOR performance has been identified to be closely related to the acidic property of the prepared samples. The increase in Al concentration resulted in the formation of strong acid sites, and the consequent MOR activity enhancement. These results provide valuable knowledge and favor the application of transition metals doped hierarchical zeolite for electrocatalytic MOR. [ABSTRACT FROM AUTHOR]

Here we report a redox-anchoring strategy for synthesizing a non-noble metal carbide (MoCx) nanocomposite electrocatalyst for water electrolysis in acidic media, using glucose and ammonium heptamolybdate as carbon and Mo precursors, respectively, without the need of gaseous carbon sources such as CH4. Specifically, the aldehyde groups of glucose are capable of reducing Mo6+ to Mo4+ (MoO2), and thus molybdenum species can be well anchored by a redox reaction onto a carbon matrix to prevent the aggregation of MoCx nanoparticles during the following carbonization process. The morphology and chemical composition of the electrocatalysts were well characterized by BSE-SEM, TEM, XRD and XPS. The obtained MoCx−2 sample showed a reasonably high hydrogen evolution reaction (HER) activity and excellent stability in an acidic electrolyte, and its overpotential required for a current density output of 20 mA cm−2 is as low as 193 mV. Such a prominent performance is ascribed to the excellent dispersity and nano-size, and the large reactive surface area of MoCx particles. This work may open a new way to the design and fabrication of other non-noble metal carbide nanocatalysts for various electrochemical applications. [ABSTRACT FROM AUTHOR]

Although Pt/C catalysts show relatively high activities for the oxygen reduction reaction (ORR) and great potential for use in polymer electrolyte membrane fuel cells, the large amount of Pt required and the poor stability of Pt/C-based catalysts remain big challenges. Herein, mesoporous Na4Ge9O20 micro-crystals have been successfully synthesized to serve as a new kind of electrocatalyst support owing to its special structural characteristics and high structural stability. After loading a low amount of Pt (5 wt %) nanoparticles of 2-5 nm in diameter, the obtained mesoporous Pt/Na4Ge9O20 composite shows not only high electrocatalytic activity for ORR in both acidic and alkaline electrolyte media, which are comparable to those of conventional 20 wt % Pt/C, but also remarkably enhanced Pt mass-specified ORR current density and durability. Synergetic catalytic effects between loaded Pt and the support for the ORR activity has been proposed. [ABSTRACT FROM AUTHOR]

A precious-metal-free cathode catalyst, MnO2 nanorod-decorated mesoporous ZSM-5 zeolite nanocomposite (MnO2/ m-ZSM-5), has been successfully synthesized by a hydrothermal and electrostatic interaction approach for efficient electrochemical catalysis of the oxygen reduction reaction (ORR). The active MnOOH species, that is, Mn4+/Mn3+ redox couple and Brønsted acid sites on the mesoporous ZSM-5 matrix facilitate an approximately 4 e− process for the catalysis of the ORR comparable to commercial 20 wt % Pt/C. Stable electrocatalytic activity with 90 % current retention after 5000 cycles, and more importantly, excellent methanol tolerance is observed. Synergetic catalytic effects between the MnO2 nanorods and the mesoporous ZSM-5 matrix are proposed to account for the high electrochemical catalytic performance. [ABSTRACT FROM AUTHOR]

4,4′-Diaminostilbene-2,2′-disulfonic acid based fluorescent whitening agents (DSD-FWAs) are prohibited in food-contact paper and board in many countries. In this work, a reliable high-performance liquid chromatography method was developed for the simultaneous determination of 11 common DSD-FWAs in paper material. Sample preparation and extraction as well as chromatographic separation of multicomponent DSD-FWAs were successfully optimized. DSD-FWAs in prepared samples were ultrasonically extracted with acetonitrile/water/triethylamine (40:60:1, v/v/v), separated on the C18 column with the mobile phase containing tetrabutylammonium bromide, and then detected by a fluorescence detector. The limits of detection were 0.12-0.24 mg/kg, and the calibration curves showed the linear correlation ( R2 ≥ 0.9994) within the range of 8.0-100 ng/mL, which was equivalent to the range of 0.80-10 mg/kg in the sample. The average recoveries and the RSDs were 81-106% and 2-9% at two fortification levels (1.0 and 5.0 mg/kg) in paper bowls, respectively. The successful determination of 11 DSD-FWAs in food-contact paper and board obtained from local markets indicated that the newly developed method was rapid, accurate, and highly selective. [ABSTRACT FROM AUTHOR]

A high amount of heteroatom doping in carbon, although favorable for enhanced density of catalytically active sites, may lead to substantially decreased electroconductivity, which is necessary for the electrochemical oxygen reduction reaction. Herein, a relatively low amount of nitrogen was successfully doped into carbon nanotubes (CNTs) by a hydrothermal approach in one step, and the synthesized nitrogen-doped CNT (CNT-N) materials retained most of the original, excellent characteristics, such as the graphitic structure, tubular morphology, and high surface area, of CNTs. The resultant CNT-N materials, although containing a relatively low amount of nitrogen doping, exhibited high electrocatalytic ORR activity, comparable to that of 20 wt % Pt/C; long durability; and, more importantly, largely inhibited methanol crossover effect. [ABSTRACT FROM AUTHOR]

This work focuses on probing the synergetic catalytic effects in mesostructured tri-component Ru-Cu-Ce oxides in CO oxidation reaction. The crystallized nanocomposites with RuO2 and CuO nanoparticles dispersed homogeneously in the pore network of mesoporous CeO2 were synthesized by the nanocasting replication method. The greatly enhanced catalytic activity was achieved by CuO incorporating in mesoporous CeO2, and further by RuO2 incorporating in the mesostructure of CuO/CeO2. Two types of synergetic catalytic mechanisms have been preliminarily proposed to be copresent in the system: CeO2 activation by CuO through generating oxygen vacancies at CeO2/CuO interface and the CeO2 surface nearby, which consequently activate the oxygen species (O*) and enhance the CO oxidation activity of the bi-metal CuCe oxide, and the simultaneous adsorption of CO molecules and their activation in parallel on the active surface of RuO2, which results in further elevated catalytic activity. [ABSTRACT FROM AUTHOR]

Highly active and low‐cost non‐noble metal electrocatalysts for hydrogen oxidation reaction (HOR) are crucial for the large‐scale applications of fuel cells, which, unfortunately, are rarely documented up to now. Here, a facile one‐step strategy to fabricate W2C nanoparticles (≈3 nm) encased in N, P‐doped few layer carbon materials (W2C@N,P‐C, WNPC) as an efficient non‐noble metal HOR electrocatalyst simply by calcining the mixture of recrystallized phosphotungstic acid and dicyandiamide is reported. The obtained WNPC catalyst shows extraordinarily high HOR activities (1.03/0.91/0.84 mA cm−2 at 0.05 V vs reversible hydrogen electrode in 0.1 m HClO4/0.1 m KOH/0.1 m neutral phosphate buffered saline electrolytes, respectively), excellent durability during accelerated degradation tests for 10 000 cycles, and outstanding CO tolerance. These high performances are attributed to the uniform structure of WNPC, and more essentially, the synergistic effect among N, P, and C species which elevates the reducibility of WNPC, favoring the generation of abundant HOR active sites. [ABSTRACT FROM AUTHOR]