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Lung adenocarcinoma (LUAD) is a malignant tumor with high mortality. At present, the clinicopathologic feature is the main breakthrough to assess the prognosis of LUAD patients. However, in most cases, the results are less than satisfactory. Cox regression analysis was conducted in this study to obtain methylation sites with significant prognostic relevance based on mRNA expression, DNA methylation data, and clinical data of LUAD from The Cancer Genome Atlas Program database. LUAD patients were grouped into 4 subtypes according to different methylation levels using K-means consensus cluster analysis. By survival analysis, patients were grouped into high-methylation and low-methylation groups. Later, 895 differentially expressed genes (DEGs) were obtained. Eight optimal methylation signature genes associated with prognosis were screened by Cox regression analysis, and a risk assessment model was constructed based on these genes. Samples were then classified into high-risk and low-risk groups depending on the risk assessment model, and prognostic, predictive ability was assessed using survival and receiver operating characteristic (ROC) curves. The results showed that this risk model had a great efficacy in predicting the prognosis of patients, and it was, therefore, able to be an independent prognostic factor. At last, the enrichment analysis demonstrated that the signaling pathways, including cell cycle, homologous recombination, P53 signaling pathway, DNA replication, pentose phosphate pathway, and glycolysis gluconeogenesis were remarkably activated in the high-risk group. In general, we construct an 8-gene model based on DNA methylation molecular subtypes by a series of bioinformatics methods, which can provide new insights for predicting the prognosis of patients with LUAD.

The effect of porosity on the interface microenvironment and catalytic performance of carbon dioxide reduction reaction (CO2RR) is still unclear for iron- and nitrogen-doped carbon-based (Fe/N/C) materials, and previous studies mainly focus on aqueous electrode test conditions rather than a practical working environment. Herein, several Fe/N/C-based catalysts with very different pore structures were prepared and compared to understand how the surface area and micropores affect the CO2RR between aqueous electrode test and practical working conditions with a solid–gas–liquid triple-phase boundary. The apparent current density correlates positively to the surface area in both test conditions. The onset current density where hydrogen evolution reaction starts is irrelevant to the micropore fraction in the aqueous electrode test but correlates negatively to the micropore fraction in a practical working condition. The inconsistency is attributed to different reaction interfaces in both cases, resulting in different interface microenvironments in different pore size ranges. This work helps in designing porous electrocatalysts for CO2RR or beyond.

A sulfur-modified Li surface is constructed and demonstrated to induce the selectively fast decomposition of LiTFSI to generate a robust inorganics-rich solid-electrolyte interphase (IR-SEI), thereby achieving highly reversible Li plating/stripping behaviors.

The structural tailoring of pores is essential to high-performance Fe/N/C electrocatalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells. Current strategies for pore structure engineering are usually accompanied with a drastic change of the intrinsic activity-related surface, which may mask the real effects of the porous structure on ORR activity. Herein, a mild carbon dioxide (CO2) etching method was used to flexibly tailor the pore structure of Fe/N/C electrocatalysts without drastic changes in their surface structure and property. In this way, via employing the Fe/N/C electrocatalysts as a model, the intrinsic impact of the pore structure on ORR activity was revealed. In addition, the CO2etching method developed a high-quality electrocatalyst (sample Fe/N/C–5% CO2) with polarization performance exceeding that of the commercial Pt/C catalyst in the fuel cell working voltage region (>0.65 V). This work will promote the ongoing intensive studies on the rational design of the pore structures in the Fe/N/C electrocatalysts.

In this paper, we describe the synthesis of the AC-PtNi/G catalysts with graphene as the carrier, viathe alcohol reduction and the sulfuric acid treatment. The prepared catalysts were microscopically characterized by X-ray diffractometry(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), electron spectroscopy(EDAX), and transmission electron micros-copy(TEM). We tested the electrochemical performance of the prepared catalysts using an electrochemical workstation and in situinfrared spectroscopy(FTIR). The results showed that the acid-treated AC-PtNi/G catalysts had a more uniform dispersion and with the increased of treatment time, the particle size of the catalyst became smaller. And the electrocatalytic performance of the AC-PtNi/G-48h catalyst treated with sulfuric acid for 48 h was significantly better than that of the untreated PtNi/G catalyst. Its electrochemically active surface area was 76.63 m2/g, and the peak current density value for catalytic oxidation of ethanol was 1218.83 A/g, which was 10 times that of ordinary commercial Pt/C catalyst. The steady-state current density value of 1100 s was 358.77 A/g, and it has excellent anti-CO toxicity performance. It was determined that a sulfuric acid treatment controlled catalyst particle size and increased the electrocatalytic activity of the catalytic oxidation of ethanol.

The synthesis of surface composition-tunable Pt-based octahedral nanoalloys is key to unravel the structure-property relationship in fuel cells. Herein, we report a facile route to prepare composition-tunable PtCu octahedral nanoalloys by using halogen ions (Br-or/and I-) as composition modulators. Among these PtCu octahedral nanoalloys, Pt59Cu41octahedron exhibits the highest catalytic activity and durability in alkaline solution. The specific activity/mass activity of Pt59Cu41octahedron is 20.25 mA cm-2/3.24 A mg-1Pt, which is 6.64/5.3 times higher than commercial Pt black in 0.5 mol L-1CH3OH, respectively. In the case of using ethanol (0.5 mol L-1) as fuel source, Pt59Cu41octahedron shows much better catalytic activity, that is 34.84 mA cm-2/5.58 A mg-1Ptfor specific activity/mass activity, which is 9.16/7.34 times higher than commercial Pt black, respectively. In situFourier transform infrared spectroscopy is employed to detect the intermediate species and products for methanol/ethanol oxidation reaction and a plausible mechanism is proposed to explain the improved activity and durability of Pt59Cu41octahedron toward methanol/ethanol oxidation in alkaline medium.

The oxygen vacancies and spinel inverse of MnFe2O4were effectively healed via a eutectic molten salt treatment, resulting in more ATdsited Mn2+active sites and higher conductivity for the improved oxygen reduction reaction (ORR) performance.

Recently, the preparation of a high-performance one-dimensional alloy nanostructure for fuel cells has been given increasing attention due to its smart-structure merits and electronic effect triggered by alloying different kinds of metals at the nanoscale. In this study, unique ternary PtCuCo nanochains assembled with small polyhedra are first achieved and used as high-performance anode electrocatalysts toward methanol oxidation at elevated temperature (60 °C) that is closer to the operating temperature of direct methanol fuel cells than room temperature. The specific activity/mass activity of Pt45Cu35Co20one-dimensional nanochains can reach up to 18.24 mA cm–2/4.19 A mg–1Ptthat is 9.25/10.47 times that of commercial Pt black in sulfuric acid medium. After a 3600 s durability test, the remaining current density of Pt45Cu35Co20one-dimensional nanochains is 73.3 times that of commercial Pt black. The structure characterizations show that the high density of surface active sites, d-band center of the Pt downshift, moderate strain effect, and synergetic effect are jointly responsible for the enhanced electrocatalytic performance of one-dimensional ternary PtCuCo nanochains.

The integrated micro proton exchange membrane fuel cells (μPEMFCs) were fabricated by constructing the hierarchical dot-type flow fields on Si wafers and then being compacted with the carbon black as gas diffusion layer (GDL) and Pt/C catalyst layer, which presents the simplicity and good device-integrity by replacing the traditional carbon paper or cloth as GDL and omitting the hot-press processing. The Si-compatible processes, including the template assembly of SiO2spheres, dry etching, channel dicing, were elaborately manipulated to optimize the wafer-scale hierarchical flow field and thus industriously improve the fluids transport and gas distribution. Ultimately, the peak power of over 1W/cm2was accomplished when the graphite bipolar plates were replaced by the hierarchical Si-based flow fields alone, while the maximum power of 354 mW/cm2was successfully demonstrated in the integrated Si-based μPEMFCs with measured size of 4 cm2. This work not only broadens the application of PEMFCs to micro/nano-electro-mechanical systems (M/NEMS) or other Si-based electronic devices, but also provides guidelines for fabricating other metal-air batteries such as Zn-air batteries and Al-air batteries.

As a cost-effective element, Mg has been applied as doped inactive atom to improve the electrochemical performance of sodium-ion cathode materials. Herein, we report Mg-substituted Na0.67Mn0.65Ni0.2Co0.15-xMgxO2composites as high-performance cathode for sodium-ion batteries and investigate the underlying working mechanism using in situinvestigation techniques to monitor the operando changes of electrodes. In situX-ray diffraction investigation demonstrates P2-type structure is well preserved even charged to 4.3 V and the changes of lattice parameters and unit cell volume of Na0.67Mn0.65Ni0.2Mg0.15O2are alleviated viaMg replacement. As a result, the capacity retention increases from 62% in Na0.67Mn0.65Ni0.2Co0.15O2to 94% in Na0.67Mn0.65Ni0.2Mg0.15O2. Meanwhile, less CO2evolution was detected in the coin cell with Na0.67Mn0.65Ni0.2Mg0.15O2electrode than in that with Na0.67Mn0.65Ni0.2Co0.15O2electrode in online differential electrochemical mass spectrometry test, suggesting a depressed side reaction between electrode and electrolyte after Mg completely replacing Co. In situelectrochemical impedance spectroscopy investigation further proves Mg is beneficial for the interfacial conductivity enhancement compared to Co, which provides evidence for enhanced high rate capabilities. These comprehensive results provide new viewpoints to explain the improved cycling and rate capabilities from the aspects of crystal structure evolution, coin cell gas evolution and electrolyte/electrode interface conductivity during charge/discharge process.

Articular cartilage has poor capability of regeneration due to the avascular surrounding and low metabolic activity. Kartogenin (KGN), an emerging nonprotein heterocyclic compound, was screened to stimulate chondrogenic differentiation of bone mesenchymal stem cells (BMSCs). Coculturing BMSCs and chondrocytes was reported to overcome the shortcomings of forming fibroblastic and hypertrophic cartilages. In this study, KGN was incorporated into the Col-Tgel hydrogel to form a Gel/Cell/KGN complex, which fabricated an appropriate microenvironment for effective cartilage regeneration of BMSCs and/or chondrocytes. The complexes that incorporated KGN, BMSCs, and chondrocytes achieved higher lubricin expression and extracellular matrix production, such as characteristic glycosaminoglycans (GAGs) and collagen type II (COL II), compared to the monocultures of BMSCs or chondrocytes in vitro. The complexes compounding KGN, BMSCs, and chondrocytes (at an optimal ratio in the in vitroexperiment) were transplanted into rat models to evaluate the repair effects. Our results suggested that the interaction between BMSCs and chondrocytes can substitute the use of growth factors to some degree and indicated the role of KGN in chondrogenesis induction. Besides, it is the first time (to our knowledge) that the expression of lubricin was found to be delayed in the coculture of mixed cells comparing with GAGs and COL II, which could be significant in cartilage tissue engineering.

Owing to high specific capacity of ∼250 mA h g–1, lithium-rich layered oxide cathode materials (Li1+xNiyCozMn(3–x–2y–3z)/4O2) have been considered as one of the most promising candidates for the next-generation cathode materials of lithium ion batteries. However, the commercialization of this kind of cathode materials seriously restricted by voltage decay upon cycling though Li-rich materials with high cobalt content have been widely studied and show good capacity. This research successfully suppresses voltage decay upon cycling while maintaining high specific capacity with low Co/Ni ratio in Li-rich cathode materials. Online continuous flow differential electrochemical mass spectrometry (OEMS) and in situ X-ray diffraction (XRD) techniques have been applied to investigate the structure transformation of Li-rich layered oxide materials during charge–discharge process. The results of OEMS revealed that low Co/Ni ratio lithium-rich layered oxide cathode materials released no lattice oxygen at the first charge process, which will lead to the suppression of the voltage decay upon cycling. The in situ XRD results displayed the structure transition of lithium-rich layered oxide cathode materials during the charge–discharge process. The Li1.13Ni0.275Mn0.580O2cathode material exhibited a high initial medium discharge voltage of 3.710 and a 3.586 V medium discharge voltage with the lower voltage decay of 0.124 V after 100 cycles.

Understanding the mechanism of CO2hydrogenation to methanol is important in the context of renewable energy storage from societal and technological point of view. We use density functional theory calculations to study systematically the effect of the size of Cu clusters on the binding strengths of reactants and reaction intermediates as well as the activation barriers for the elementary reaction steps underlying CO2hydrogenation. All the elementary reaction barriers exhibit linear scaling relationships with CO and O adsorption energies. Used in microkinetics simulations, we predict that medium-sized Cu19clusters exhibit the highest CO2hydrogenation activity which can be ascribed to a moderate CO2coverage and a low CO2dissociation barrier. The nanoscale effect is evident from the strong variation of CO and O adsorption energies for clusters with 55 or less Cu atoms. The reactivity of larger clusters and nanoparticles is predicted to depend on surface atoms with low coordination number. Optimum activity is correlated with the bond strength of reaction intermediates determined by the d-band center location of the Cu clusters and the extended surfaces. The presented size-activity relations provide useful insight for the design of better Cu catalysts with maximum mass-specific reactivity for CO2hydrogenation performance.

Proton exchange membrane fuel cells suffer from the sluggish kinetics of the oxygen reduction reaction (ORR) and the high cost of Pt catalysts. In the present work, a high-performance ORR catalyst based on Fe, N, S-doped porous carbon (FeNS-PC) was synthesized using melamine formaldehyde resin as C and N precursors, Fe(SCN)3as Fe and S precursors, and CaCl2as a template via a two-step heat treatment without a harsh template removal step. The results show that the catalyst treated at 900 °C (FeNS-PC-900) had a high surface area of 775 m2/g, a high mass activity of 10.2 A/g in an acidic medium, and excellent durability; the half-wave potential decreased by only 20 mV after 10000 potential cycles. The FeNS-PC-900 catalyst was used as the cathode in a proton exchange membrane fuel cell and delivered a peak power density of 0.49 W/cm2. FeNS-PC-900 therefore has good potential for use in practical applications.

Tuning the electronic structure of heterogeneous metal catalysts has emerged as an effective strategy to optimize their catalytic activities. By preparing ethylenediamine-coated ultrathin platinum nanowires as a model catalyst, here we demonstrate an interfacial electronic effect induced by simple organic modifications to control the selectivity of metal nanocatalysts during catalytic hydrogenation. This we apply to produce thermodynamically unfavourable but industrially important compounds, with ultrathin platinum nanowires exhibiting an unexpectedly high selectivity for the production of N-hydroxylanilines, through the partial hydrogenation of nitroaromatics. Mechanistic studies reveal that the electron donation from ethylenediamine makes the surface of platinum nanowires highly electron rich. During catalysis, such an interfacial electronic effect makes the catalytic surface favour the adsorption of electron-deficient reactants over electron-rich substrates (that is, N-hydroxylanilines), thus preventing full hydrogenation. More importantly, this interfacial electronic effect, achieved through simple organic modifications, may now be used for the optimization of commercial platinum catalysts.

This study aims to understand the effects of functional agents such as capping agents, stabilizers, surfactants and additives in shape-controlled synthesis of nanomaterials. The well-defined Pt(100) single crystal surface was used as a model to investigate its interaction with citrate, a capping agent that is often used in shape-controlled synthesis of nanomaterials. It demonstrated that, through a systematic study of electrochemical cyclic voltammetry, the presence of citrate in solution could increase the current peak density of hydrogen adsorption at high potential (jp,L), while decrease proportionally the current peak density of hydrogen adsorption at low potential (jp,S). Furthermore, the increase of citrate concentration shifted negatively the peak potentials (Ep,Land Ep,S) of both jp,Land jp,S. The results indicated that the interaction of citrate with Pt(100) surface could induce increasing the (100) surface domains of two-dimensional long range order (2D-(100)), and decreasing the (100) surface domains of one-dimensional short range order (1D-(100)). It also revealed that the interaction of citrate with Pt(100) surface could stabilize the 2D-(100) structure. The findings gained in this study implied that the citrate may lead to form stable 2D-(100) domains on Pt nanoparticles upon the shape-controlled synthesis of Pt nanomaterials.This study aims to understand the effects of functional agents such as capping agents, stabilizers, surfactants and additives in shape-controlled synthesis of nanomaterials. The well-defined Pt(100) single crystal surface was used as a model to investigate its interaction with citrate, a capping agent that is often used in shape-controlled synthesis of nanomaterials. It demonstrated that, through a systematic study of electrochemical cyclic voltammetry, the presence of citrate in solution could increase the current peak density of hydrogen adsorption at high potential (jp,L), while decrease proportionally the current peak density of hydrogen adsorption at low potential (jp,S). Furthermore, the increase of citrate concentration shifted negatively the peak potentials (Ep,Land Ep,S) of both jp,Land jp,S. The results indicated that the interaction of citrate with Pt(100) surface could induce increasing the (100) surface domains of two-dimensional long range order (2D-(100)), and decreasing the (100) surface domains of one-dimensional short range order (1D-(100)). It also revealed that the interaction of citrate with Pt(100) surface could stabilize the 2D-(100) structure. The findings gained in this study implied that the citrate may lead to form stable 2D-(100) domains on Pt nanoparticles upon the shape-controlled synthesis of Pt nanomaterials.

Abstract: Biological reduction of O2 to H2O justifies a serious look at heme as a potential O2 reduction reaction (ORR) catalyst for low temperature fuel cells. In this study, a novel non-platinum electrocatalyst for ORR was prepared through hemin, which is hydrochloride of heme, supported on Black Pearls 2000 carbon black (Hm-BP) pyrolyzed at 700–900 °C in Ar atmosphere. The physical and electrocatalytic properties of as-prepared catalysts were characterized by TGA, XRD, XPS, TEM, rotating disk electrode (RDE) and rotating ring disk electrode (RRDE). It has found that the catalyst treated at 750 °C (Hm-BP-750) exhibits the best property among the Hm-BP catalysts prepared. The onset potential of ORR on the Hm-BP-750 at 30 °C was measured ca. 0.90 V (vs. RHE) in 0.1 M H2SO4, and mass current density was reached 15.3 mA mg−1 at 0.75 V. It has revealed that O2 could be reduced directly to water in a 4e process between 0.9 and 0.83V, and the yield of H2O2 was 0–18% in the potential range of 0.83–0.63 V. This methanol-tolerant catalyst also presents excellent stability in medium-term test of direct methanol fuel cell at 80 °C.

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Efficiency simplified: A synthetic strategy has been developed to prepare singlecrystalline hollow PdPt nanocubes right, see picture; left: nanocubes. Compared to the solid PdPt nanocubes of similar sizes, the hollow PdPt nanocubes increase accessible surface area and therefore improve electrocatalytic activity in formic acid oxidation.

Einfacher effizient: Eine Synthesestrategie wird vorgestellt, die einkristalline hohle PdPtNanowürfel liefert rechts im Bild; links: PdNanowürfel. Verglichen mit ähnlich großen kompakten PdPtNanowürfeln haben die hohlen PdPtNanowürfel eine größere zugängliche Oberfläche und damit eine höhere Aktivität bei der elektrokatalytischen Ameisensäureoxidation.

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Dissociative adsorption and electrooxidation of dimethyl ether (DME) on a platinum electrode in different pH solutions were studied using cyclic voltammetry (CV) and in situFTIR reflection spectroscopy. The coverage of the dissociative adsorbed species was measured about 70% from hydrogen adsorption-desorption region (0.05-0.35 V ( vsRHE)) of steady-state voltammogram recorded in 0.1 mol·L −1H 2SO 4solution. It was found that the electrochemical reactivity of DME was pH dependent, i.e., the larger the pH value was, the less the reactivity of DME would be. No perceptible reactivity of DME in 0.1 mol·L −1NaOH solution could be detected. It was revealed that the protonation of the oxygen atom in the C-O-C bond played a key role in the electrooxidation of DME. In situFTIR spectroscopic results illustrated that linearly bonded CO (CO L) species determined at low potential region were derived from the dissociative adsorption of DME and behaved as ‘poisoning’ intermediate. The CO Lspecies could be oxidized to CO 2at potential higher than 0.55 V ( vsRHE) and in the potential range from 0.75 to 1.00 V ( vsRHE) DME was oxidized simultaneously viaHCOOH species that were identified as the reactive intermediates.

The electrochemical processes of irreversibly adsorbed antimony (Sb ad) on Au electrode were investigated by cyclic voltammetry (CV) and electrochemical quartz crystal microbalance (EQCM). CV data showed that Sb adon Au electrode yielded oxidation and reduction features at about 0.15 V ( vssaturated calomel electrode, SCE). EQCM data indicated that Sb adspecies were stable on Au electrode in the potential region from −0.25 to 0.18 V ( vsSCE); the adsorption of Sb inhibited the adsorption of water and anion on Au electrode at low electrode potentials. Sb 2O 3species was suggested to form on the Au electrode at 0.18 V. At a potential higher than 0.20 V the Sb 2O 3species could be further oxidized to Sb(V) oxidation state and then desorbed from Au electrode.