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1.
Front Immunol ; 15: 1430571, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39131156

RESUMEN

Background: Intermediate-stage (BCLC-B) hepatocellular carcinoma (HCC) beyond the up-to-11 criteria represent a significant therapeutic challenge due to high and heterogeneous tumor burden. This study evaluated the effectiveness and safety of transarterial chemoembolization (TACE) in combination with lenvatinib and tislelizumab for these patients. Methods: In this retrospective cohort study, patients with unresectable intermediate-stage HCC beyond the up-to-11 criteria were enrolled and divided into TACE monotherapy (T), TACE combined with lenvatinib (TL), or TACE plus lenvatinib and tislelizumab (TLT) group based on the first-line treatment, respectively. The primary endpoint was overall survival (OS). The secondary outcomes included progression-free survival (PFS), tumor response according to RESIST1.1 and modified RECIST, and adverse events (AEs). Results: There were 38, 45, and 66 patients in the T, TL, and TLT groups, respectively. The TLT group exhibited significantly higher ORR and DCR than the other two groups, as assessed by either mRECIST or RECIST 1.1 (all P<0.05). Median PFS and OS were significantly longer in the TLT group compared with the T group (PFS: 8.5 vs. 4.4 months; OS: 31.5 vs. 18.5 months; all P<0.001) and TL group (PFS: 8.5 vs. 5.5 months; OS: 31.5 vs. 20.5 months; all P<0.05). The incidence of TRAEs was slightly higher in the TLT and TL groups than in the T group, while all the toxicities were tolerable. No treatment-related death occurred in all groups. Conclusions: TACE combined with lenvatinib and tislelizumab significantly improved the survival benefit compared with TACE monotherapy and TACE plus lenvatinib in patients with intermediate-stage HCC beyond the up-to-11 criteria, with an acceptable safety profile.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Compuestos de Fenilurea , Quinolinas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/tratamiento farmacológico , Quinolinas/uso terapéutico , Quinolinas/administración & dosificación , Quinolinas/efectos adversos , Masculino , Femenino , Persona de Mediana Edad , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Quimioembolización Terapéutica/métodos , Compuestos de Fenilurea/uso terapéutico , Compuestos de Fenilurea/administración & dosificación , Compuestos de Fenilurea/efectos adversos , Estudios Retrospectivos , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Adulto , Estadificación de Neoplasias , Resultado del Tratamiento
2.
Artículo en Inglés | MEDLINE | ID: mdl-39115112

RESUMEN

We demonstrate that the ß-polymorph of zinc dicyanamide, Zn[N(CN)2]2, can be efficiently used as a negative electrode material for lithium-ion batteries. Zn[N(CN)2]2 exhibits an unconventional increased capacity upon cycling with a maximum capacity of about 650 mAh·g-1 after 250 cycles at 0.5C, an increase of almost 250%, and then maintaining a large reversible capacity of more than 600 mAh·g-1 for 150 cycles. Such an increased capacity is primarily attributed to the increased level of activity in the conversion reaction. A combination of conversion-type and alloy-type mechanisms is revealed in this anode material via advanced characterization studies and theoretical calculations. This mechanism, observed here for the first time in transition-metal dicyanamides, is probably responsible for the outstanding electrochemical performance. We believe that this study guides the development of new high-capacity anode materials.

3.
Adv Sci (Weinh) ; : e2404701, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940403

RESUMEN

The development of the electric vehicle industry has spurred demand for secondary batteries capable of rapid-charging and slow-discharging. Among them, sodium-ion batteries (SIBs) with layered oxide as the cathode exhibit competitive advantages due to their comprehensive electrochemical performance. However, to meet the requirements of rapid-charging and slow-discharging scenarios, it is necessary to further enhance the rate performance of the cathode material to achieve symmetrical capacity at different rates. Simultaneously, minimizing lattice strain during asymmetric electrochemical processes is also significant in alleviating strain accumulation. In this study, the ordered distribution of transition metal layers and the diffusion pathway of sodium ions are optimized through targeted K-doping of sodium layers, leading to a reduction of the diffusion barrier and endowment of prominent rate performance. At a 20C rate, the capacity of the cathode can reach 94% of that at a 0.1C rate. Additionally, the rivet effect of the sodium layers resulted in a global volume strain of only 0.03% for the modified cathode during charging at a 10C rate and discharging at a 1C rate. In summary, high-performance SIBs, with promising prospects for rapid-charging and slow-discharging capability, are obtained through the regulation of sodium layers, opening up new avenues for commercial applications.

4.
Adv Mater ; 36(32): e2404640, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38775475

RESUMEN

Cathode materials of sodium-based batteries with high specific capacity and fast charge-discharge mode, as well as ultralong reversible cycles at wide applied temperatures, are essential for future development of advanced energy storage system. Developing transition metal selenides with intercalation features provides a new strategy for realizing the above cathode materials. Herein, this work reports a storage mechanism of sodium ion in hexagonal CuSe (h-CuSe) based on the density functional theory (DFT) guidance. This work reveals that the two-dimensional ion intercalation triggers localized redox reaction in the h-CuSe bulk phase, termed intercalation-induced localized conversion (ILC) mechanism, to stabilize the sodium storage structure by forming localized Cu7Se4 transition phase and adjusting the near-edge coordination state of the Cu sites to achieve high reversible capacity and ultra-long cycling life, while allowing rapid charge-discharge cycling over a wide temperature range.

5.
Langmuir ; 40(17): 9255-9264, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38630628

RESUMEN

The solid-state lithium sulfur battery (SSLSB) is an attractive next-generation energy storage system by reason of its remarkably high energy density and safety. However, the SSLSB still faces critical challenges, such as sluggish reaction kinetics, mismatched interface, and undesirable reversible capacity. Herein, a high-performance SSLSB is reported using sulfurized polyacrylonitrile with rich selenium-doped sulfur (Se/S-S@pPAN) as a cathode and poly(ethylene oxide)/Li7La3Zr1.4Ta0.6O12 (PEO-LLZTO) as an electrolyte. The sulfur content of the cathode up to 60.9 wt % can be achieved by dispersing selenium sulfide (SeSx) species in the sulfurized polyacrylonitrile (S@pPAN) skeleton at a molecular level. Selenium as a eutectic accelerator can be uniformly distributed in the composite through the Se-S bond and can accelerate the reaction kinetics. The PEO-LLZTO hybrid solid-state electrolyte (SSE) displays an attractive electrochemical performance and provides an intimate contact with electrodes. At 60 °C, Se/S-S@pPAN delivers an impressive discharge capacity of 1042 mAh g-1 at 0.1C and 445 mAh g-1 at 1C. Additionally, the LiFePO4 cathodes combined with PEO-LLZTO deliver a high reversible capacity (158.9 mAh g-1, 1C) and an ultralong lifespan (a capacity retention of 80%, 1000 cycles) at 1C. The synergetic design of the high-performance sulfur cathode and the organic/inorganic hybrid electrolyte is crucial for enabling the high-performance SSLSB.

6.
Small ; 20(30): e2312011, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38431933

RESUMEN

Recently, coupling the conventional low Pt-group-metal (low-PGM, LP) and emerging PGM-free (PF) moiety to form a composite LP/PF catalyst is proposed to be an advanced strategy to improve the intrinsic activity and stability of oxygen reduction reaction (ORR) catalysts. Milestones in terms of ORR mass activity are created by this type of catalyst. However, the specific synergy between LP and PF moieties has not been well elucidated. Herein, two model catalysts are synthesized, i.e., atomically dispersed Co/N/C supporting Pt single atoms (Co/N/C@Pt-SAs) and PtCo nanoparticles (Co/N/C@PtCo-NPs). Interestingly, the Co/N/C@PtCo-NPs catalyst presents higher ORR mass activity prior to Co/N/C@Pt-SAs. This is theoretically due to the dual "built-in electric field" in Co/N/C@PtCo-NPs: one electric field with a direction from Pt to Co in NPs and another from Pt to Co/N/C; that is, Pt gains higher electron density in Co/N/C@PtCo-NPs than that in Co/N/C@Pt-SAs, thus forming an asymmetric electron cloud, and regulating the adsorption and activation of oxygen-containing species. In addition, the existence of Co significantly decreases the average valence state of PtCo NPs, indicating a stronger affinity between PtCo NPs and Co/N/C substrate, to account for the enhanced stability.

7.
Adv Mater ; 36(4): e2308193, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37847882

RESUMEN

Rechargeable batteries are widely used as power sources for portable electronics, electric vehicles and smart grids. Their practical performances are, however, largely undermined under extreme conditions, such as in high-altitude drones, ocean exploration and polar expedition. These extreme environmental conditions not only bring new challenges for batteries but also incur unique battery failure mechanisms. To fill in the gap, it is of great importance to understand the battery failure mechanisms under different extreme conditions and figure out the key parameters that limit battery performances. In this review, the authors start by investigating the key challenges from the viewpoints of ionic/charge transfer, material/interface evolution and electrolyte degradation under different extreme conditions. This is followed by different engineering approaches through electrode materials design, electrolyte modification and battery component optimization to enhance practical battery performances. Finally, a short perspective is provided about the future development of rechargeable batteries under extreme conditions.

8.
J Biol Chem ; 299(11): 105316, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37797697

RESUMEN

Lack of estradiol production by granulosa cells blocks follicle development, causes failure of estrous initiation, and results in an inability to ovulate. The ubiquitin-proteasome system plays a critical role in maintaining protein homeostasis and stability of the estrous cycle, but knowledge of deubiquitination enzyme function in estradiol synthesis is limited. Here, we observe that the deubiquitinase ubiquitin C-terminal hydrolase 1 (UCHL1) is more significant in estrous sows and high litter-size sows than in nonestrous sows and low-yielding sows. Overexpression of UCHL1 promotes estradiol synthesis in granulosa cells, and interference with UCHL1 has the opposite effect. UCHL1 binds, deubiquitinates, and stabilizes voltage-dependent anion channel 2 (VDAC2), promoting the synthesis of the estradiol precursor pregnenolone. Cysteine 90 (C90) of UCHL1 is necessary for its deubiquitination activity, and Lys45 and Lys64 in VDAC2 are essential for its ubiquitination and degradation. In vivo, compared with WT and sh-NC-AAV groups, the estrus cycle of female mice is disturbed, estradiol level is decreased, and the number of antral follicles is decreased after the injection of sh-UCHL1-AAV into ovarian tissue. These findings suggest that UCHL1 promotes estradiol synthesis by stabilizing VDAC2 and identify UCHL1 as a candidate gene affecting reproductive performance.


Asunto(s)
Estradiol , Ubiquitina Tiolesterasa , Canal Aniónico 2 Dependiente del Voltaje , Animales , Femenino , Ratones , Células de la Granulosa/metabolismo , Folículo Ovárico/metabolismo , Porcinos , Ubiquitina Tiolesterasa/metabolismo , Canal Aniónico 2 Dependiente del Voltaje/metabolismo , Sus scrofa
9.
J Hepatocell Carcinoma ; 10: 1209-1222, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37533600

RESUMEN

Purpose: The current therapeutic strategies for high-risk, unresectable hepatocellular carcinoma (HCC) patients demonstrate suboptimal outcomes. This study aimed to assess the clinical efficacy of the combined approach of hepatic arterial infusion chemotherapy (HAIC), lenvatinib, and tislelizumab, either with or without transhepatic arterial embolization (TAE), in managing HCC patients with portal vein tumor thrombus (PVTT) and significant tumor load. Patients and Methods: In this multicenter retrospective study, we analyzed patients diagnosed with primary, unresectable HCC presenting with PVTT and substantial tumor load who had undergone treatment with HAIC, lenvatinib, and tislelizumab, with or without TAE (referred to as the THLP or HLP group), between January 2019 and February 2022 across four medical centers in China. The outcomes included objective response rate (ORR), disease control rate (DCR), overall survival (OS), and progression-free survival (PFS). Results: The study cohort comprised 100 patients, 50 each in the THLP and HLP groups. The THLP group demonstrated a significantly superior ORR (72% vs 52%, P=0.039). However, both groups exhibited comparable DCR (88% vs 76%, P=0.118), as assessed by the modified response evaluation criteria in solid tumors. The median OS and PFS for the entire cohort were 12.5 months (95% CI, 10.9-14.8) and 5.0 months (95% CI, 4.2-5.4), respectively. The THLP group exhibited a significantly extended OS (median, 14.1 vs 11.3 months, P=0.041) and PFS (median, 5.6 vs 4.4 months, P=0.037) in comparison to the HLP group. The most frequently reported treatment-related adverse events included abdominal pain and nausea, both reported by 59% of patients. Conclusion: The combination of HAIC, lenvatinib, tislelizumab, and TAE was feasible in HCC patients with PVTT and high tumor burden, with tolerable safety.

11.
Adv Mater ; 35(41): e2304022, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37358536

RESUMEN

Electrochemical oxygen evolution reaction (OER) kinetics are heavily correlated with hybridization of the transition metal d-orbital and oxygen intermediate p-orbital, which dictates the barriers of intermediate adsorption/desorption on the active sites of catalysts. Herein, a strategy is developed involving strain engineering and coordination regulation to enhance the hybridization of Ni 3d and O 2p orbitals, and the as-synthesized Ni-2,6-naphthalenedicarboxylic acid metal-organic framework (DD-Ni-NDA) nanosheets deliver a low OER overpotential of 260 mV to reach 10 mA cm-2 . By integrating an alkaline anion exchange membrane electrolyzer and Pt/C electrode, 200 and 500 mA cm-2 current densities are reached with cell voltages of 1.6 and 2.1 V, respectively. When loaded on a BiVO4 photoanode, the nanosheet enables highly active solar-driven water oxygen. Structural characterizations together with theoretical calculations reveal that the spin state of the centre Ni atoms is regulated by the tensile strain and unsaturated coordination defects in DD-Ni-NDA, and such spin regulation facilitates spin-dependent charge transfer of the OER. Molecular orbital hybridization analysis reveals the mechanism of OH* and OOH* adsorption energy regulation by changes in the DD-Ni-NDA spin state, which provides a deeper understanding of the electronic structure design of catalysts for the OER.

12.
Adv Mater ; 35(36): e2303297, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37272677

RESUMEN

Bi-based materials are one of the most promising candidates for electrochemical CO2 reduction reaction (CO2 RR) to formate; however, the majority of them still suffer from low current density and stability that essentially constrain their potential applications at the industrial scale. Surface modification represents an effective approach to modulate the electrode microenvironment and the relative binding strength of key intermediates. Herein, it is demonstrated that the surface comodification with halides and alkali metal ions from the conversion of Bi-based halide perovskite nanocrystals is a viable strategy to boost the CO2 RR performance of Bi for formate electrosynthesis. Cs3 Bi2 I9 nanocrystals are prepared by a hot-injection method. The as-prepared products feature well-defined hexagonal shape and uniform size distribution. When used as the precatalyst, Cs3 Bi2 I9 nanocrystals are converted to Cs+ and I- comodified Bi. The resultant catalyst exhibits high formate Faradaic efficiency close to 100%, and remarkable partial current density up to 44 mA cm-2 in an H-cell and up to 276 mA cm-2 in a flow cell. Moreover, Cs3 Bi2 I9 is used as the cathode catalyst and paired with an Al anode in an Al-CO2 battery for simultaneous CO2 valorization and power generation.

13.
Small Methods ; 7(7): e2201247, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37086116

RESUMEN

Realizing efficacious π-donation from the O 2p orbital to electron-deficient metal (t2g ) d-orbitals along with separately tuned adsorption of *O and *OOH, is an imperious pre-requisite for an electrocatalyst design to demonstrate boosted oxygen evolution reaction (OER) performance. To regulate the π-donation and the adsorption ability for *O and *OOH, herein, a facile strategy to modulate the electron transfer from electron-rich t2g -orbitals to electron-deficient t2g -orbitals, via strong π-donation from the π-symmetry lone pairs of the bridging O2- , and the d-band center of a biomimetic honeycomb (BHC)-like nanoarchitecture (Ir1- x (Ir0.8 V0.2 O2 )x -BHC) is introduced. The suitable integration of V heteroatoms in the single crystal system of IrO2 decreases the electron density on the neighboring Ir sites, and causes an upshift in the d-band center of Ir1- x (Ir0.8 V0.2 O2 )x -BHC, weakening the adsorption of *O while strengthening that of *OOH, lowers the energy barrier for OER. Therefore, BHC design demonstrates excellent OER performance (shows a small overpotential of 238 mV at 10 mA cm-2 and a Tafel slope of 39.87 mV dec-1 ) with remarkable stability (130 h) in corrosive acidic electrolyte. This work opens a new corridor to design robust biomimetic nanoarchitectures of modulated π-symmetry (t2g ) d-orbitals and the band structure, to achieve excellent activity and durability in acidic environment.

14.
Angew Chem Int Ed Engl ; 62(20): e202302547, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36919817

RESUMEN

Non-equilibrium kinetic intermediates are usually preferentially generated instead of thermodynamic stable phases in the solid-state synthesis of layered oxides. Understanding the inherent complexity between thermodynamics and kinetics is important for designing high cationic ordering cathodes. Single-crystal strategy is an effective way to solve the intrinsic chemo-mechanical problems of Ni-rich cathodes. However, the synthesis of high-performance single-crystal is very challenging. Herein, the kinetic reaction path and the formation mechanism of non-equilibrium intermediates in the synthesis of single-crystal Co-free Ni-rich were explored. We demonstrate that the formation of non-equilibrium intermediate and the electrochemical-thermo-mechanical failure can be effectively inhibited by driving low-temperature topotactic lithiation. This work provides a basis for designing high-performance single-crystal Ni-rich layered oxides by regulating the defective structures.

15.
Nanomicro Lett ; 15(1): 75, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36976391

RESUMEN

Lithium-sulfur batteries with liquid electrolytes have been obstructed by severe shuttle effects and intrinsic safety concerns. Introducing inorganic solid-state electrolytes into lithium-sulfur systems is believed as an effective approach to eliminate these issues without sacrificing the high-energy density, which determines sulfide-based all-solid-state lithium-sulfur batteries. However, the lack of design principles for high-performance composite sulfur cathodes limits their further application. The sulfur cathode regulation should take several factors including the intrinsic insulation of sulfur, well-designed conductive networks, integrated sulfur-electrolyte interfaces, and porous structure for volume expansion, and the correlation between these factors into account. Here, we summarize the challenges of regulating composite sulfur cathodes with respect to ionic/electronic diffusions and put forward the corresponding solutions for obtaining stable positive electrodes. In the last section, we also outlook the future research pathways of architecture sulfur cathode to guide the develop high-performance all-solid-state lithium-sulfur batteries.

16.
Nat Commun ; 14(1): 1081, 2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36841814

RESUMEN

The electrochemical stability window of the electrolyte solution limits the energy content of non-aqueous lithium metal batteries. In particular, although electrolytes comprising fluorinated solvents show good oxidation stability against high-voltage positive electrode active materials such as LiNi0.8Co0.1Mn0.1O2 (NCM811), the ionic conductivity is adversely affected and, thus, the battery cycling performance at high current rates and low temperatures. To address these issues, here we report the design and synthesis of a monofluoride ether as an electrolyte solvent with Li-F and Li-O tridentate coordination chemistries. The monofluoro substituent (-CH2F) in the solvent molecule, differently from the difluoro (-CHF2) and trifluoro (-CF3) counterparts, improves the electrolyte ionic conductivity without narrowing the oxidation stability. Indeed, the electrolyte solution with the monofluoride ether solvent demonstrates good compatibility with positive and negative electrodes in a wide range of temperatures (i.e., from -60 °C to +60 °C) and at high charge/discharge rates (e.g., at 17.5 mA cm-2). Using this electrolyte solution, we assemble and test a 320 mAh Li||NCM811 multi-layer pouch cell, which delivers a specific energy of 426 Wh kg-1 (based on the weight of the entire cell) and capacity retention of 80% after 200 cycles at 0.8/8 mA cm-2 charge/discharge rate and 30 °C.

17.
Artículo en Inglés | MEDLINE | ID: mdl-36753671

RESUMEN

Layered oxides LiNixCoyMnzO2 are widely used as the main cathode material for high-energy lithium-ion batteries. Over long-term cycling, irreversible phase transformations in layered oxides usually occur along with the loss of active lithium, which directly reflects in the sharp decrease of capacity. However, it is difficult to accurately and rapidly determine lithium content in aged materials, raising extreme impediments in the direct recycling of layered oxides. Herein, we propose a facile method for quick and accurate calculation of the residual lithium content through the developed relationship of shear strain and the states of charge. Based on this recognization, a discharge capacity close to the original capacity of the pristine material is achieved in the regenerated material by combining a hydrothermal method with annealing treatment. The recycled material demonstrates a dramatic improvement in electrochemical properties, especially the high rate performance. This method not only effectively realizes the quantitative regeneration of cathode materials but also provides a possible strategy for the future development of direct regeneration.

18.
Adv Mater ; 35(12): e2210658, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36641734

RESUMEN

CO2 utilization and conversion are of great importance in alleviating the rising CO2 concentration in the atmosphere. Here, a single-atom catalyst (SAC) is reported for electrochemical CO2 utilization in both aqueous and aprotic electrolytes. Specifically, atomically dispersed Mn-N4 sites are embedded in bowl-like mesoporous carbon particles with the functionalization of epoxy groups in the second coordination spheres. Theoretical calculations suggest that the epoxy groups near the Mn-N4 site adjust the electronic structure of the catalyst with reduced reaction energy barriers for the electrocatalytic reduction of CO2 to CO. The resultant Mn-single-atom carbon with N and O doped catalyst (MCs-(N,O)) exhibits extraordinary electrocatalytic performance with a high CO faradaic efficiency of 94.5%, a high CO current density of 13.7 mA cm-2 , and a low overpotential of 0.44 V in the aqueous environment. Meanwhile, as a cathode catalyst for aprotic Li-CO2 batteries, the MCs-(N,O) with well-regulated active sites and unique mesoporous bowl-like morphology optimizes the nucleation behavior of discharge products. MCs-(N,O)-based batteries deliver a low overpotential and excellent cyclic stability of 1000 h. The findings in this work provide a new avenue to design and fabricate SACs for various electrochemical CO2 utilization systems.

19.
Angew Chem Int Ed Engl ; 62(10): e202215406, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36593654

RESUMEN

Cu-based catalysts have been widely applied in electroreduction of carbon dioxide (CO2 ER) to produce multicarbon (C2+ ) feedstocks (e.g., C2 H4 ). However, the high energy barriers for CO2 activation on the Cu surface is a challenge for a high catalytic efficiency and product selectivity. Herein, we developed an in situ *CO generation and spillover strategy by engineering single Ni atoms on a pyridinic N-enriched carbon support with a sodalite (SOD) topology (Ni-SOD/NC) that acted as a donor to feed adjacent Cu nanoparticles (NPs) with *CO intermediate. As a result, a high C2 H4 selectivity of 62.5 % and an industrial-level current density of 160 mA cm-2 at a low potential of -0.72 V were achieved. Our studies revealed that the isolated NiN3 active sites with adjacent pyridinic N species facilitated the *CO desorption and the massive *CO intermediate released from Ni-SOD/NC then overflowed to Cu NPs surface to enrich the *CO coverage for improving the selectivity of CO2 ER to C2 H4 .

20.
Small Methods ; 7(3): e2201596, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36703553

RESUMEN

Novel methods and mechanisms for graphene fabrication are of great importance in the development of materials science. Herein, a facile method to directly convert carbonaceous salts into high-quality freestanding graphene via a simple one-step redox reaction, is reported. The redox couple can be a combination of sodium borohydride (reductant) and sodium carbonate (oxidant), which can readily react with each other when evenly mixed/calcined and yield gram-scale, high-quality, contamination-free, micron-sized, freestanding graphene. More importantly, this method is applicable to a variety of input reductants and oxidants that are low cost and easily accessible. An in-depth investigation reveals that the carbonaceous oxidants can not only provide reduced carbon mass for graphene formation but also act as a self-template to guide the polymerization of carbon atoms following the pattern of the monolayer, six-carbon rings. In addition, the direct formation of graphene exhibits theoretically lower energy barriers than that of other allotropes such as fullerene and carbon nanotube. This facile, low-cost, scalable, and applicable method for mass production of high-quality graphene is expected to revolutionize graphene fabrication technology and boost its practical application to the industry level.

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