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Given the high energy density and eco-friendly characteristics, lithium-carbon dioxide (Li-CO 2 ) batteries have been considered to be a next-generation energy technology to promote carbon neutral and space exploration. However, Li-CO 2 batteries suffer from sluggish reaction kinetics, causing large overpotential and poor energy efficiency. Here, we observe enhanced reaction kinetics in aprotic Li-CO 2 batteries with unconventional phase 4H/face-centered cubic (fcc) iridium (Ir) nanostructures grown on gold template. Significantly, 4H/fcc Ir exhibits superior electrochemical performance over fcc Ir in facilitating the round-trip reaction kinetics of Li + -mediated CO 2 reduction and evolution, achieving a low charge plateau below 3.61 V and high energy efficiency of 83.8%. Ex situ/in situ studies and theoretical calculations reveal that the boosted reaction kinetics arises from the highly reversible generation of amorphous/low-crystalline discharge products on 4H/fcc Ir via the Ir-O coupling. The demonstration of flexible Li-CO 2 pouch cells with 4H/fcc Ir suggests the feasibility of using unconventional phase nanomaterials in practical scenarios.

Summary Electrocatalytic CO2 reduction reaction (CO2RR) has attained great attention as it can transform the greenhouse gas CO2 to value-added chemicals, such as carbon monoxide, formic acid, ethylene, ethanol, and n-propanol. However, the electrocatalytic performance of materials, especially the metal materials, toward the CO2RR is still limited due to the complex reaction processes and broad product distribution. Very recently, surface modification of metal materials has emerged as an effective way to boost their electrocatalytic CO2RR performance. Herein, recent advances in the surface modification of metal materials, which includes surface molecular functionalization, surface elemental doping, and surface plasma treatment, for CO2RR are presented. The surface modification-induced variations of surface states and electrocatalytic performances of metal materials, together with the underlying mechanisms, are highlighted. It is believed that the development of surface modification could promote the rational design and preparation of advanced CO2RR electrocatalysts toward practical applications.

Over the past few decades, gold-based materials have drawn extensive attention due to their intriguing physical/chemical properties and excellent performance in a broad range of applications. In particular, the remarkable technical progress in synthesis and characterization is promoting the rapid development of gold-based nanoalloys, which are of great significance in catalysis. In this review, we provide a brief overview of the recently reported gold-based nanoalloys, focusing on their general synthetic methods and potential catalytic applications. In particular, the general relationships between material structures/compositions and catalytic performances are discussed in representative chemical reactions, such as the carbon dioxide reduction reaction (CO2RR), oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), oxygen evolution reaction (OER), small organic molecule oxidation reaction, carbon monoxide oxidation reaction, and typical heterogeneous catalytic reactions in chemical engineering. Furthermore, critical challenges and potential opportunities facing gold-based nanoalloys are proposed to provide possible inspiration for future material design towards high performance applications.

Because of the distinct electronic structures and stable chemical properties, rhodium materials are one of the most important noble metal catalysts for various kinds of industrial chemical processe...

The traditional energy consumption mode has caused many environmental problems and the rise of the energy crisis as well. On the one hand, the reserves of unrenewable fossil energies, such as coal, oil, and natural gas, are quite limited. On the other hand, the excessive consumption of fossil energies has emitted too many environmental unfriendly products, such as the greenhouse gas CO2. In the past decade, the average CO2 emissions in the world was as high as about 32.53 billion tons per year. In 2019, the CO2 concentration in the atmosphere reached 412 ppm. The large concentration of CO2 in the atmosphere has caused many serious environmental problems, such as global warming, ocean acidification, sea-level rise, glacier melting, and climate change. To solve these problems, one way is to replace the fossil energies with renewable clean energies like wind and solar electricity, which can decrease the CO2 emissions. However, wind and solar electricity suffer from an intermittent supply, unstable frequency, and hard delivery. Another way is to directly convert CO2 to other high-value chemicals and fuels with proper physicochemical methods, like thermochemical conversion, electrochemical reduction, and photocatalytic reduction. Very recently, with the combination of the aforementioned two ways, electrochemical CO2 reduction reaction (eCO2RR) powered by clean wind and solar electricity has become the most promising solution to address the CO2-caused environmental problems. Firstly, eCO2RR can be well coupled to the local clean energy power plants to fully utilize the clean electricity by converting CO2 to value-added chemicals and fuels. Secondly, eCO2RR is an efficient technique to achieve a carbon neutral cycle. Thirdly, the eCO2RR system runs under mild conditions with relative high energy efficiency.

Electrocatalytic carbon dioxide reduction reaction (CO

Electrochemical reduction of CO2 has been considered as a promising method for the production of value-added chemicals. In this work, the electrochemical reduction of CO2 to formate is carried out over novel carbon aerogel supported SnO2 nanocrystals prepared by a facile hydrothermal method. The as prepared materials exhibit good catalytic activity and high formate selectivity. It is found that the content of SnO2 plays an important role in the whole process, in which the formate is the exclusive product. At low SnO2 content the catalyst shows poor activity due to the lack of active ingredients, while at high SnO2 content it results in a dramatic decrease of the faradaic efficiency for the formate because of the blockage of part of active sites due to the agglomeration and poor conductivity of SnO2. It is also found that the optimized SnO2/CA-80 with 28.1 wt.% SnO2 leads to the best performance, offering a relatively high faradaic efficiency of ∼76% for the formate formation in 1.0 mol/L KHCO3 at −0.96 V (vs. RHE). Moreover, the above catalyst exhibits excellent stability during the control potential electrolysis for 12 h.

OBJECTIVEIn China, orthopedics and neurosurgery are among the most desired majors for medical students. However, little is known about the working and living status of specialists in these two fields. This study was aimed at evaluating job satisfaction, engagement, and burnout in the population of Chinese orthopedist and neurosurgeon trainees.METHODSA nationwide online survey was administered in mainland China. Questionnaires were answered anonymously. Job satisfaction, engagement, and burnout were assessed using the Job Descriptive Index, the Utrecht Work Engagement Scale, and the Maslach Burnout Inventory, respectively.RESULTSData were collected from 643 orthopedist trainees and 690 neurosurgeon trainees. Orthopedists and neurosurgeons showed no statistical difference in terms of age, sex, job titles, and preference for working in tertiary hospitals. Orthopedists had a higher marriage rate (p < 0.01), a lower divorce rate (p = 0.017), relatively shorter working hours (p < 0.01), and a higher annual income (p = 0.023) than neurosurgeons. Approximately 40% of respondents experienced workplace violence in the last 5 years. Less than 10% of respondents were satisfied with their pay, and over 70% would not encourage their offspring to become a doctor. Orthopedists were more satisfied with their careers than neurosurgeons (p < 0.01) and had a higher level of work engagement (p < 0.01). In addition, a higher proportion of orthopedists were burnt out (p < 0.01) than neurosurgeons, though the difference between the two groups was not significant (p = 0.088). Multivariate regressions suggested that younger age (≤ 25 years old), being a senior trainee, getting divorced, working in a regional hospital, long working hours (≥ 71 hrs/wk), a low annual income (CONCLUSIONSChinese orthopedic surgical and neurosurgical trainees are under significant stress. Orthopedic surgeons showed relatively optimistic data in their assessments of job satisfaction, engagement, and burnout. This study may provide valuable information for orthopedic and neurosurgical candidates considering either specialty as a career.

ObjectivesChinese neurosurgery has made great progress during the past decades; yet, little is known about the working status of neurosurgeons. This study aimed to evaluate the difference between academic and non-academic neurosurgeons, focusing on their professional burnout, job satisfaction and work engagement.DesignCross-sectional nationwide survey.Study settingThe survey was conducted in China between 2017 and 2018.ParticipantsA total number of 823 academic neurosurgeons and 379 non-academic neurosurgeons participated in this study.Outcome measuresProfessional burnout, job satisfaction and work engagement were assessed using the Maslach Burnout Inventory, the Job Descriptive Index and the Utrecht Work Engagement Scale, respectively.ResultsThe majority of respondents were male (92.93%), less than 45 years old (85.27%) and married (79.53%). Chinese neurosurgeons worked 63.91±11.04 hours per week, and approximately 45% experienced burnout. Compared with non-academic respondents, academic neurosurgeons had longer working hours (pConclusionChinese neurosurgeons are under significant stress particularly for the non-academic neurosurgeons. Offering better opportunities for training, promotion, higher income and safer working environments could be solutions to relieve burnout and improve career satisfaction and engagement.Trial registration numberChiCTR1800014762. This article is not linked to a clinical trial.

An energy-effective polyaniline coated graphite felt (PANI@GF) composite cathode for the electro-Fenton (E-Fenton) process was synthesized through an electro-polymerization method. The electrocatalytic activity of the cathode for the 2e− ORR process was investigated and dimethyl phthalate (DMP) was used as a model substrate to evaluate its performance in the E-Fenton process. The as-prepared PANI@GF composite possessed a three-dimensional porous structure, which is favorable for O2 diffusion, while the large amount of N atoms in the conductive polyaniline (PANI) enhanced 2e− ORR reactivity. The DMP degradation of the E-Fenton system using PANI@GF was significantly enhanced owing to the improvement in ORR performance. The apparent kinetic constant for DMP degradation was 0.0753 min−1, five times larger than that of GF. The optimal carbonization temperature and polymerization time for the preparation of the PANI@GF composite cathode was found to be 900 °C and 1 h, respectively. Measurement conditions are a crucial factor for proper evaluation of cathode electrocatalytic performance. Accordingly, the O2 flow rate, Fe2+ concentration, and pH for DMP degradation were optimized at 0.4 L/min, 1.0 mmol/L, and 3.0, respectively. These results indicate that the present PANI@GF composite cathode is energy-effective and promising for potential use as an E-Fenton system cathode for the removal of organic pollutants in wastewater.

The exploration of efficient nonprecious metal‐based oxygen evolution reaction (OER) electrocatalysts is of great significance. Herein, both size‐ and component‐tuned FeNi oxynitride are prepared and employed for electrocatalytic water oxidation. Combining the excellent metal‐like feature of induced OER activity of nitrides and oxidation resistance performance of oxides, the obtained FeNi oxynitride delivers an outstanding OER performance. The synergistic interplay between Fe, Ni components creates a favorable local coordination environment for OER and decreased sizes enables more active sites exposure. As a result, under 1 M KOH, the optimized material displays highly efficient electrocatalytic OER performance with low overpotential 295 mV (10 mA cm−2 catalytic current density) and considerable durability. These findings open up opportunities to explore other excellent catalysts through multicomponent strong interactions coupled with size control. This work was financially supported by the National NaturalScience Foundation of China (Nos. 21606113 and 21676128),and the International Postdoctoral Exchange Fellowship byChina Postdoctoral Science Foundation (No. 20170055).

Due to their unique activity towards formation of alcohols and hydrocarbons, copper (Cu) based catalysts have been widely used in the electrochemical reduction of carbon dioxide (ERCD). Cu foam naturally possesses three-dimensional (3D) porous structure and catalytically active Cu elements, exhibiting very good catalytic ability for ERCD. Herein, nanostructured self-supporting Cu electrodes with Cu foam as the substrate, with progressive morphologies of nanowires (CuNW), nanosheets (CuNS) and nanoflowers (CuNF), are in-situ prepared by simply adjusting the reaction time in a strongly alkaline oxidizing solution. It is found that the performance and products distribution of ERCD are affected by both the morphology of the as prepared nanostructured self-supporting Cu electrodes and the electrolyte species. As electrode micromorphology evolves from nanowire to nanoflower, the initial electrode potential required for C2 products generation shifts to more positive values. The CuNS electrode shows the highest Faradaic efficiency (FE) of 86.9% at −0.4 V (vs. RHE) and superior performance, owing to its nanosheet morphology that can better stabilize the intermediate state products. Moreover, both total FE and products distribution are affected by the electrolyte anion species. The highest total FE in the investigated electrolyte on CuNS electrode obeys the following order: KHCO3 (86.9%, −0.4 V (vs. RHE)) > KCl (54.7%, −0.5 V (vs. RHE)) > KH2PO4 (1.0%, −0.9 V (vs. RHE)). In 1.0 mol L−1 KHCO3, the CuNS electrode shows a very complex products distribution; in 1.0 mol L−1 KCl, the products distribution can be feasibly controlled by the applied potential; while in 1.0 mol−1 L KH2PO4, ERCD is almost totally suppressed by hydrogen evolution reaction (HER). It is the first time that the CuNS electrodes are applied for ERCD with low cost, simple synthesis, easy scale-up and high activity. Combined with the flexible control ability in FE and products distribution, CuNS electrode possesses great potential for the industrial application of ERCD.