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To better grasp the dynamic trend of the transformation and development of thermal power enterprises in the context of low carbon worldwide; the background of the transformation development of thermal power enterprises, the low carbon economic model, and the basic situation of the thermal power industry are reviewed and analyzed. Yearly quantitative distribution of literature, country (region) distribution, main source journal distribution, organization distribution, research hotspots, and frontiers are all analyzed, CiteSpace and Vosviewer are used to plot expertise area maps. The results show that the number of studies on the transformation and development of thermal power plants under the background of low carbon is on the rise in general, among which the contribution of China is the largest. Research articles have been published in 77 publications worldwide, mainly in the fields of chemistry, materials, and fuels. The framework of simple theories and research strategies has been completed. However, the research community is too targeted and there are few frontier branches. Based on technology development, process updating and process development, environmental remediation, electrochemical CO2 reduction, organic contaminants, active sites, and bifunctional electrocatalysts have become the leading research topics of thermal power plant transformation development. [ABSTRACT FROM AUTHOR]

Ofloxacin (OFLX) and norfloxacin (NFLX) are typical quinolone antibacterials used in medicine, aquaculture, and animal husbandry in China. The abusive use of antibiotics has led to the presence of OFLX and NFLX in surface water and groundwater. Due to similarities in the molecular structure of OFLX and NFLX, their simultaneous detection has been challenging. In this study, a simple and highly sensitive electrochemical sensor for the simultaneous detection of OFLX and NFLX was developed using a graphene modified glassy carbon electrode (ERGO/GCE), which was prepared by the electrochemical reduction method. With electrochemical reduction, oxygen-containing groups in graphene oxide (GO) were deoxidized to electrochemically reduced graphene oxide (ERGO) and can effectively separate the overlapping oxidation peaks of OFLX and NFLX with a 136 mV peak potential difference. The mechanism of these oxidation processes was analyzed by comparing the Fourier transform infrared (FTIR) of OFLX and NFLX electrochemical response on prepared modified electrodes. The limitations of this electrochemical method in terms of simultaneous detection are as follows: 1.25 μM for OFLX and 2.44 μM for NFLX. This detection method was also applied in medicine and aquaculture wastewater with satisfactory results. [ABSTRACT FROM AUTHOR]

Nitrate pollution has become a serious environmental concern all over the world including in China due to the mismanagement of water resources and human activities. Agricultural runoff and industrial and nuclear waste are among the major sources of nitrate pollution. Consuming nitrate-rich water can cause many chronic diseases including digestive problems, which can lead to many types of cancer and other serious health issues. Denitrification is the natural process for nitrate reduction under aerobic conditions, but it cannot handle an excess of nitrate, so several methods have been adopted for nitrate removal, i.e., biological, chemical, physicochemical, and electrochemical reduction removal. Among all, electrochemical reduction removal is a cost-effective and environmental-friendly process. To obtain the maximal elimination efficiency ideal conditions of current intensity, pH, plate distance, initial nitrate concentration, and type of electrolyte solution should be studied for effective nitrate removal. Electrochemical reduction removal of nitrate involves the transfer of electrons and hydrogenation. Besides an efficient nitrate removal process, electrochemical reduction removal has some drawbacks like sludge formation, low selectivity for nitrogen, and production of brine that limit its long-term implementation. This review focused on nitrate pollution, previous nitrate removal strategies, and essential principles for understanding the mechanism of electrochemical reduction removal and controlling the products of the reaction. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction is regarded as a green and promising technology because it can convert carbon dioxide into value-added fuel or chemicals in a flexible and sustainable way. This research aimed to comprehensively analyze the research hotspots and trends in the field of CO2 electroreduction from 2005 to 2022 using bibliometric methods based on the core database of Web of Science. The results showed that 4546 papers on CO2 electroreduction were retrieved from 2005 to 2022, with a clear increasing trend. The research direction was diversified, involving multiple disciplines, and it is a comprehensive research field. ACS Catalysis is the journal with the largest number of articles. China is the country with the largest number of documents and has made significant contributions to the development and progress of this field. Copper-based catalysts are still the research focus in recent years. It is of great practical significance to develop copper-based catalysts with high efficiency, low cost, high stability, and high selectivity for the preparation of C1 products. [ABSTRACT FROM AUTHOR]

In the context of peak carbon and carbon neutrality, the utilization of CO2 has attracted attention with the aim of reducing carbon emissions by converting CO2 into high-value chemicals or energy. Methanol (MeOH), which is both a hydrogen and a carbon carrier, is considered the most promising among the CO2-conversion products. This paper focus on routes for electrochemical conversion of CO2 to MeOH using green power and green hydrogen to achieve negative CO2 emissions. Three feasible technical routes for electrochemical conversion of CO2 to MeOH are proposed in this paper: Route 1, electrolysis of water to H2 and hydrogenation of CO2 to MeOH; Route 2, electrochemical reduction of CO2 to MeOH; and Route 3, co-electrolysis of CO2–H2O to syngas and synthesis of MeOH from syngas. Techno-economic assessments of the three routes are conducted using technical maturity surveys, system simulations and cost analyses to provide reference data for route selection for CO2 conversion to MeOH in China. Compared with the other routes, Route 1 is advantageous in terms of technical maturity and commercial application prospects. Although Route 1 is presently economically unviable, it is expected to achieve profitability and commercial application in the future with decreases in the cost of renewable power and continuous development of water-electrolysis technology. [ABSTRACT FROM AUTHOR]

• The catalytic system and catalyst for CO 2 conversion are reviewed. • The developmental stage of CO 2 catalytic conversion in china is summarized. • The influence of hydrogen and electricity supply are discussed. • The carbon emission factor of supplying hydrogen needs to be less than 6 kg CO 2 eq/kg H 2. To achieve the global net-zero carbon emissions target, enhanced studies on how to effectively convert and utilize CO 2 have been conducted. Herein, the research progress and development trend of CO 2 conversion to chemicals, including CO 2 hydrogenation to hydrocarbons, CO 2 as an oxidant to syngas, and CO 2 cycloaddition to carbonate were discussed in this review. The principles, advantages, disadvantages, and prospects of thermal catalysis, electrocatalysis, photocatalysis, enzyme catalysis, and plasma catalysis for CO 2 conversion were summarized. Among them, the different methods of the active component, carrier, catalyst electronic effect, synergistic effect and size effect used to develop specific catalysts for different CO 2 conversions were introduced emphatically. Moreover, the developmental stage of CO 2 catalytic conversion technology and important industrial demonstration projects in China were summarized, with special emphasis on the relationship between hydrogen/electricity supply and the carbon emission reduction effect of CO 2 catalytic conversion. The reaction network, catalytic system and demonstration project of CO 2 catalytic conversion were comprehensively compared and discussed to more clearly play the beneficial role of CO 2 catalytic conversion in carbon reduction work. [Display omitted] [ABSTRACT FROM AUTHOR]

Volcanic rock found in the Longgang Volcano Group in Jilin Province of China has properties essentially similar to Apollo lunar soils and previously prepared lunar soil simulants, such as Johnson Space Center Lunar simulant and Minnesota Lunar simulant. In this study, an electrochemical method of preparation of Al-Si master alloy was investigated in 52.7 wt.%NaF-47.3 wt.%AlF melt adding 5 wt.% volcanic rock at 1233 K. The cathodic electrochemical process was studied by cyclic voltammetry, and the results showed that the cathodic reduction of Si(IV) is a two-step reversible diffusion-controlled reaction. Si(IV) is reduced to Si(II) by two electron transfers at −1.05 V versus platinum quasi-reference electrode in 52.7 wt.%NaF-47.3 wt.%AlF molten salt adding 5 wt.% volcanic rock, while the reduction peak at −1.18 V was the co-deposition of aluminum and silicon. In addition, the cathodic product obtained by galvanostatic electrolysis for 4 h was analyzed by means of x-ray diffraction, x-ray fluorescence, scanning electron microscopy and energy dispersive spectrometry. The results showed that the phase compositions of the products are Al, Si, AlFeSi, and AlSi, while the components are 90.5 wt.% aluminum, 4.4 wt.% silicon, 1.9 wt.% iron, and 0.2 wt.% titanium. [ABSTRACT FROM AUTHOR]

In this work, a three-dimensional self-supporting copper/cobalt phosphide/nickel foam (Co/CoP/NF) composite was fabricated and employed as the cathode for electrochemical nitrate removal from surface water with the assistance of a commercial Ir-Ru/Ti anode. The experimental results demonstrate that the introduction of Cu nanoparticles on CoP nanosheets is favorable for the electrocatalytic nitrate reduction. The influences of operating parameters (pH value, current density and initial nitrate concentration) on the nitrate reduction were assessed with the presence of Cl−. At the optimized conditions, the removal of nitrate exhibits an efficiency ca. 100% via the coupling electrochemical reduction and oxidation processes. Moreover, the nitrogen selectivity is found to be as high as 98.8% within 210 min, accompanied with a promising test endurance (>94.0% for total nitrogen (TN) and NO 3 − removal efficiencies after an electrochemical run of 24.5 h). Importantly, as for the treated actual surface water, the concentration of TN is smaller than 1.5 mg L−1, in accordance with the limit of Ⅳ-level standard of the surface water environmental quality in China (GB 3838-2002). The efficient removal of nitrate can be attributed to the synergistic effect of Cu and CoP microparticles to enhance the reduction activity, as well as the subsequent chloride oxidation for the major intermediate of ammonium. [Display omitted] • Fabricated Cu/CoP/NF electrode is competent for electrochemical reduction of NO 3 −. • NO 3 − easily converts into NH 4 + during electrochemical reduction process. • Coupling with anodic oxidation, selectivity of NO 3 − to N 2 ramps up to 98.8%. • The coupled denitrification system exhibits excellent TN removal and durability. • TN concentration for treated actual surface water meets the relevant standard. [ABSTRACT FROM AUTHOR]

The process of electrochemical nitrate reduction behaving the merits of sufficient efficacy and environmental benignity has attracted immense interest for the nitrate (NO 3 -) disposal. However, the practical application of this technique is seriously restricted due to the defects of generating by-products (such as ammonium and nitrite), and the presence of total nitrogen (TN) with a high concentration. In this work, a novel catalyst composite (Fe0/Ni 2 P/CC) was fabricated via the combined method involving liquid-phase reduction, electroless nickel-phosphorus plating and phosphation processes. The crystal structure, morphology, and chemical component of the obtained composite were characterized. The influences of operating parameters (pH value, current density, initial nitrate-N concentration and coexisting substances) on the NO 3 - reduction were assessed. At the optimized conditions, the synthesized Fe0/Ni 2 P/CC composite displays the fascinating performances in NO 3 - conversion (89.81%), N 2 selectivity (95.55%) and tested endurance, comparing with other three samples (i.e. Fe0 +Ni 2 P/CC, pure HER and pure Fe0). For the disposal for simulated effluent of municipal wastewater treatment plant effluent, this composite exhibits a superb NO 3 - conversion of 89.81%, and the concentration of TN (1.92 mg L−1) is lower than the threshold limit (2 mg L−1) of five-level standard for surface water of China. It is noteworthy that the Fe0/Ni 2 P/CC composite has an excellent durability (< 5% decay after 20 h reduction test), and the spent sample can be employed for the decoloring of methyl orange via the chemical advanced oxidation process (95% for decolorization efficiency). [Display omitted] • Fe0/Ni 2 P/CC composite used to remove NO 3 - was fabricated via a combined process. • Fe0/Ni 2 P/CC exhibits excellent performances of NO 3 - conversion and N 2 selectivity. • The concomitant HER process intensively extends the service life of Fe0. • Fe0/Ni 2 P/CC is competent for the advanced treatment of municipal wastewater. • The spent Fe0/Ni 2 P/CC is helpful to facilitate the decoloring of methyl orange. [ABSTRACT FROM AUTHOR]