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1.
Angew Chem Int Ed Engl ; : e202402625, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709979

RESUMO

The interfacial instability of high-nickel layered oxides severely plagues practical application of high-energy quasi-solid-state lithium metal batteries (LMBs). Herein, a uniform and highly oxidation-resistant polymer layer within inner Helmholtz plane is engineered by in-situ polymerizing 1-vinyl-3-ethylimidazolium (VEIM) cations preferentially adsorbed on LiNi0.83Co0.11Mn0.06O2 (NCM83) surface, inducing formation of anion-derived cathode-electrolyte interphase with fast interfacial kinetics. Meanwhile, the copolymerization of [VEIM][BF4] and vinyl ethylene carbonate (VEC) endows P(VEC-IL) copolymer with the positively-charged imidazolium moieties, providing positive electric fields to facilitate Li+ transport and desolvation process. Consequently, the Li||NCM83 cells with a cut-off voltage up to 4.5 V exhibit excellent reversible capacity of 130 mAh g-1 after 1000 cycles at 25 °C and considerable discharge capacity of 134 mAh g-1 without capacity decay within 100 cycles at -20 °C. This work provides deep understanding on tailoring electric double layer by cation specific adsorption for high-voltage quasi-solid-state LMBs.

2.
Nano Lett ; 24(12): 3710-3718, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38484178

RESUMO

Two-dimensional (2D) van der Waals (vdW) heterostructures have attracted widespread attention in photocatalysis. Herein, we employ a novel strategy utilizing first-principles high-throughput inverse design of 2D Z-scheme heterojunctions for photocatalysis. This approach is anchored in high-throughput screening conditions, which are fundamentally based on the characteristics of carrier mechanisms influenced significantly by Z-scheme heterojunctions. A pivotal element of our screening process is the integration of the indirect-to-direct bandgap transition with momentum-matching band alignment in k-space, guiding us to combine two 2D indirect bandgap monolayers into direct Z-scheme heterojunctions characterized by pronounced interlayer excitons. Various stacking modes introduce extra and distinct degrees of freedom that can be useful for tuning the properties of heterostructures, encompassing factors such as components, stacking patterns, and sequences. We demonstrate that various stacking modes can facilitate the indirect-to-direct bandgap transition and the emergence of interlayer excitons. These findings provide exciting opportunities for designing Z-scheme heterojunctions in photocatalysis.

3.
J Phys Chem Lett ; 15(7): 2096-2104, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38358755

RESUMO

Excitonic effects caused by the Coulomb interaction between electrons and holes play a crucial role in photocatalysis at the molecule/metal oxide interface. As an ideal model for investigating the excitonic effect, coadsorption and photodissociation of water and methanol molecules on titanium dioxide involve complex ground-state thermalcatalytic and excited-state photocatalytic reaction processes. Herein, we systemically investigate the excited-state electronic structures of the coadsorption of H2O and CH3OH molecules on a rutile TiO2(110) surface by linear-response time-dependent density functional theory calculations and probe the reaction path for generating HCOOH or CO2, from ground-state and excited-state perspectives. The reaction barriers in excited-state calculations are significantly different from those in ground-state calculations during three processes, with the largest decrease being 0.94 eV for the Ti5c-O-CH2-O-Ti5c formation process.

4.
BMC Psychiatry ; 23(1): 682, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726709

RESUMO

BACKGROUND: Prescribing the optimal antipsychotic treatment to schizophrenia is very important as it is well established that patients have different sensitivity to the available antipsychotic drugs. The genotype of the HTR2A T102C (rs6313) polymorphism has been suggested to affect the efficacy of antipsychotic drugs, but the results of different studies have been inconsistent METHODS: In this study, a meta-analysis was used to ascertain the association between allele and genotype polymorphism of rs6313 and the efficacy of antipsychotic drugs. Related studies publicated from January 1995 to December 2021 were retrieved from PubMed, Embase, ScienceDirect, and Web of Science databases. The correlations between allele and genotype polymorphism of rs6313 and the responder rate and scale score reduction rate of antipsychotics were analyzed. In addition, subgroup analyses were performed on time, drug, and ethnicity. RESULTS: A total of 18 studies were included. The meta-analysis showed that allele and genotype polymorphisms at the rs6313 locus overall were not associated with antipsychotic drug responder rate or scale score reduction rate. Ethnicity subgroup analysis showed that antipsychotic drugs were more effective in patients with allele T in the Caucasian population. Indian patients with the TT genotype had the lowest scale score reduction rate and poor drug treatment effect. East Asian patients with the TC genotype had better treatment effect, whereas in patients with the CC genotype, the treatment was less effective. Drug subgroup analysis showed that patients with the TC genotype treated with clozapine had the highest responder rate and score reduction rate. CONCLUSIONS: The association between rs6313 polymorphism and the efficacy of antipsychotic drugs is mainly influenced by drug and ethnicity. Caucasian patients with the T allele respond better to drug therapy, and Asian patients with TC genotype. The TC genotype was also a good predictor of the efficacy of clozapine treatment.


Assuntos
Antipsicóticos , Clozapina , Receptor 5-HT2A de Serotonina , Humanos , Alelos , Antipsicóticos/uso terapêutico , Etnicidade , Genótipo , Receptor 5-HT2A de Serotonina/genética
5.
ACS Nano ; 17(4): 3901-3912, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36753692

RESUMO

The physicochemical properties of a semiconductor surface, especially in low-dimensional nanostructures, determine the electrical and optical behavior of the devices. Thereby, the precise control of surface properties is a prerequisite for not only preserving the intrinsic material quality but also manipulating carrier transport behavior for promoting device characteristics. Here, we report a facile approach to suppress the photocorrosion effect while boosting the photoresponse performance of n-GaN nanowires in a constructed photoelectrochemical-type photodetector by employing Co3O4 nanoclusters as a hole charging layer. Essentially, the Co3O4 nanoclusters not only alleviate nanowires from corrosion by optimizing the oxygen evolution reaction kinetics at the nanowire/electrolyte interface but also facilitate an efficient photogenerated carrier separation, migration, and collection process, leading to a significant ease of photocurrent attenuation (improved by nearly 867% after Co3O4 decoration). Strikingly, a record-high responsivity of 217.2 mA W-1 with an ultrafast response/recovery time of 0.03/0.02 ms can also be achieved, demonstrating one of the best performances among the reported photoelectrochemical-type photodetectors, that ultimately allowed us to build an underwater optical communication system based on the proposed nanowire array for practical applications. This work provides a perspective for the rational design of stable nanostructures for various applications in photo- and biosensing or energy-harvesting nanosystems.

6.
J Phys Chem Lett ; 13(28): 6532-6540, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35829739

RESUMO

The activation of C-H bonds at low temperatures has attracted widespread interest in heterogeneous catalysis, which involves complex thermocatalytic and photocatalytic reaction processes. Herein, we systematically investigate the photothermal catalytic process of C-H bond activation in C2H6 dehydrogenation on rutile TiO2(110). We demonstrate that the photochemical activity of the C2H6 molecule adsorbed on TiO2(110) is site-sensitive and that C2H6 is more easily adsorbed at the Ti5c site with a lower dehydrogenation energy barrier. The first C-H bond activation of the C2H6 adsorbed at the Ti5c site tends to occur in the ground state, whereas Obr-adsorbed C2H6 is more photoactive during the initial adsorption. During the dehydrogenation of C2H6, the photogenerated electrons are always located at the Ti4+ sites of the TiO2 substrate while the photogenerated holes can be captured by C2H6 to activate the C-H bond.

7.
J Phys Chem Lett ; 13(1): 1-11, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34941268

RESUMO

Direct Z-scheme photocatalyst possess promising potential to utilize solar radiation for photocatalytic overall water splitting; however, the design and characterization remain challenging. Here, we construct and verify a direct Z-scheme heterojunction using edge-modified phosphorene-nanoribbons (X-PNRs, where X = OH and OCN) with first-principles ground-state and excited-state density functional theory (DFT) calculations. The ground-state calculations provide fundamental properties such as geometric structure and band alignment. The linear-response time-dependent DFT (LR-TDDFT) calculations exhibit the photogenerated charge distribution and demonstrate the generation of interlayer excitons in heterojunctions, which are advantageous to the electron-hole recombination in Z-scheme heterojunctions. The ultrafast charge transfer at the interface studied by time-dependent ab initio nonadiabatic molecular dynamics (NAMD) simulations indicates that interlayer electron-hole recombination is prior to intralayer recombination for the OH/OCN-PNRs heterojunction, showing the characteristics of a Z-scheme heterojunction. Therefore, our computational work provides a universal strategy to design direct Z-scheme heterojunction photocatalysts for overall water splitting.

8.
Nat Commun ; 12(1): 6335, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732747

RESUMO

Single-atom catalysts are becoming increasingly significant to numerous energy conversion reactions. However, their rational design and construction remain quite challenging due to the poorly understood structure-function relationship. Here we demonstrate the dynamic behavior of CuN2C2 site during operando oxygen reduction reaction, revealing a substrate-strain tuned geometry distortion of active sites and its correlation with the activity. Our best CuN2C2 site, on carbon nanotube with 8 nm diameter, delivers a sixfold activity promotion relative to graphene. Density functional theory and X-ray absorption spectroscopy reveal that reasonable substrate strain allows the optimized distortion, where Cu bonds strongly with the oxygen species while maintaining intimate coordination with C/N atoms. The optimized distortion facilitates the electron transfer from Cu to the adsorbed O, greatly boosting the oxygen reduction activity. This work uncovers the structure-function relationship of single-atom catalysts in terms of carbon substrate, and provides guidance to their future design and activity promotion.

9.
ACS Appl Mater Interfaces ; 13(24): 28252-28260, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34101431

RESUMO

The lithium-sulfur (Li-S) battery with a high theoretical energy density (2560 Wh kg-1) is one of the most promising candidates in next-generation energy storage systems. However, its practical application is impeded by the shuttle effect of lithium polysulfides, huge volume expansion, and overgrowth dendrite of lithium. Herein, we propose an artificial conformal agar polymer coating on a lithium anode (marked as A-Li). The functional layer facilitating the formation of a compact interphase on the lithium anode can effectively accommodate expansive volume and restrain the growth of dendritic lithium. The Li/Li symmetric cell with A-Li delivers stable plating/stripping cycling over 300 h at a high current density of 3.0 mA cm-2 and a high fixed areal capacity of 3.0 mAh cm-2. The cycle life of Li-Cu cells with A-Li is twice longer than that of pristine cells, and the Li-S batteries equipped with A-Li anodes also deliver an enhanced specific capacity and high Coulombic efficiencies. This work provides a pathway to protect metal Li anodes and contributes to the development of high-performance Li-S batteries.

10.
ACS Appl Mater Interfaces ; 13(21): 24565-24574, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34009930

RESUMO

Rechargeable Mg-ion batteries typically suffer from either rapid passivation of the Mg anode or severe corrosion of the current collectors by halogens within the electrolyte, limiting their practical implementation. Here, we demonstrate the broadly applicable strategy of forming an artificial solid electrolyte interphase (a-SEI) layer on Mg to address these challenges. The a-SEI layer is formed by simply soaking Mg foil in a tetraethylene glycol dimethyl ether solution containing LiTFSI and AlCl3, with Fourier transform infrared and ultraviolet-visible spectroscopy measurements revealing spontaneous reaction with the Mg foil. The a-SEI is found to mitigate Mg passivation in Mg(TFSI)2/DME electrolytes with symmetric cells exhibiting overpotentials that are 2 V lower compared to when the a-SEI is not present. This approach is extended to Mg(ClO4)2/DME and Mg(TFSI)2/PC electrolytes to achieve reversible Mg plating and stripping, which is not achieved with bare electrodes. The interfacial resistance of the cells with a-SEI protected Mg is found to be two orders of magnitude lower than that with bare Mg in all three of the electrolytes, indicating the formation of an effective Mg-ion transporting interfacial structure. X-ray absorption and photoemission spectroscopy measurements show that the a-SEI contains minimal MgCO3, MgO, Mg(OH)2, and TFSI-, while being rich in MgCl2, MgF2, and MgS, when compared to the passivation layer formed on bare Mg in Mg(TFSI)2/DME.

11.
Phys Chem Chem Phys ; 22(48): 28414-28422, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33305303

RESUMO

Tellurene, a two-dimensional (2D) semiconductor, meets the requirements for optoelectronic applications with desirable properties, such as a suitable band gap, high carrier mobility, strong visible light absorption and high air stability. Here, we demonstrate that the band engineering of zigzag tellurene nanoribbons (ZTNRs) via edge-modification can be used to construct highly efficient heterojunction solar cells by using first-principles density functional theory (DFT) calculations. We find that edge-modification enhances the stability of ZTNRs and halogen-modified ZTNRs showing suitable band gaps (1.35-1.53 eV) for sunlight absorption. Furthermore, the band gaps of ZTNRs with tetragonal edges do not strongly depend on the edge-modification and ribbon width, which is conducive to experimental realization. The heterojunctions constructed by halogen-modified ZTNRs show desirable type 2 band alignments and small band offsets with reduced band gaps and enhanced sunlight absorption, resulting in high power conversion efficiency (PCE) in heterojunction solar cells. In particular, the calculated maximum PCE of designed heterojunction solar cells based on halogen-modified ZTNRs can reach as high as 22.6%.

12.
Chem Commun (Camb) ; 56(98): 15458-15461, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33241235

RESUMO

The most processable solid electrolyte, Li2S-P2S5 (LPS), exhibits the drawback of a limited potential window, which leads to the deterioration of the interface stability and limits the application of high-capacity anodes, such as those based on Li, Si, and Bi. Here, the in situ formation of a designed artificial solid electrolyte interface provides an effective way to apply low-voltage anodes in solid-state batteries.

13.
Chem Commun (Camb) ; 56(84): 12797-12800, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-32966392

RESUMO

Black phosphorus modified sulfurized polyacrylonitrile (BP-SPAN) is reported for the first time for Li-S batteries operated in ether electrolyte. The amorphous P2S5+x in BP-SPAN is crucial to suppress the shuttling effect of polysulfides and enhance the reaction kinetics. It delivers an amazing capacity of 1086 mA h g-1 (2C) and capacity retention of 91.1% (0.1C, 100th).

14.
Phys Chem Chem Phys ; 22(23): 12973-12979, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32507864

RESUMO

Palladium diselenide (PdSe2) is a two-dimensional (2D) transition metal dichalcogenide (TMD) semiconductor with desirable properties for nanoelectronics. Here, we demonstrate that 2D layered PdSe2 adsorbed with two kinds of organic molecules, an electrophilic molecule tetracyano-p-quinodimethane (TCNQ) as an electron acceptor and a nucleophilic molecule tetrathiafulvalene (TTF) as an electron donor, can realize tunable p-type and n-type doping of 2D PdSe2 by using first-principles density functional theory (DFT) calculations. We find that TCNQ attracts electrons from PdSe2 and introduces shallow acceptor states close to the valence band edge, resulting in p-type doping of PdSe2, while TTF donates electrons into PdSe2 and introduces shallow donor states close to the conduction band edge, resulting in n-type doping of PdSe2. Furthermore, such p-type and n-type doping of PdSe2 can be efficiently controlled with an external electric field, interlayer distance and substrate thickness. Such effective bipolar doping of PdSe2via molecular adsorption would broaden its applications in nanoelectronics.

15.
Angew Chem Int Ed Engl ; 59(37): 15902-15907, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32436325

RESUMO

The essence of developing a Pt-based single-atom catalyst (SAC) for hydrogen evolution reaction (HER) is the preparation of well-defined and stable single Pt sites with desired electrocatalytic efficacy. Herein, we report a facile approach to generate uniformly dispersed Pt sites with outstanding HER performance via a photochemical reduction method using polyvinylpyrrolidone (PVP) molecules as the key additive to significantly simplify the synthesis and enhance the catalytic performance. The as-prepared catalyst displays remarkable kinetic activities (20 times higher current density than the commercially available Pt/C) with excellent stability (76.3 % of its initial activity after 5000 cycles) for HER. EXAFS measurements and DFT calculations demonstrate a synergetic effect, where the PVP ligands and the support together modulate the electronic structure of the Pt atoms, which optimize the hydrogen adsorption energy, resulting in a considerably improved HER activity.

16.
ACS Appl Mater Interfaces ; 11(43): 39970-39978, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31592626

RESUMO

Lithium-ion batteries with high electrochemical performance and stable mechanical compliance are pivotal to propel the advanced wearable electronics forward. Herein, a high-conductive flexible electrode densified from multilayer lamellar unit cells with the silicon-based sandwich structure is rationally designed by molecular engineering. Silicon nanoparticles can be uniformly anchored to the surface of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized bacterial cellulose (TOBC) aerogel through hydrogen bonding, which effectively relaxes the drastic volume expansion of the Si-based anode. The graphite microsheets (GMs) attached on silicon nanoparticles allow the porous aerogel network to maintain excellent electrical connection in all directions, and after being switched to compact film, the conductive network enables a robust contact with silicon nanoparticles. As a result, the Si-based nanomat anode exhibits reliable cycling stability (639.4 mA h g-1 after 400 cycles at 1.0 A g-1) and enhanced rate capability (298.6 mA h g-1 at 1.6 A g-1). Notably, instead of conventional polyolefin separators, TOBC-reinforced silica aerogel is fabricated as an advanced separator to integrate the flexible all-in-one full-cell with freestanding GM/TOBC/silicon (GM/TOBC/Si) anode and GM/TOBC/LiFePO4 cathode. Driven by the unique structure and functional component, the flexible all-in-one lithium-ion batteries showcase exceptional deformation tolerance yet impressive charge/discharge behavior.

17.
Angew Chem Int Ed Engl ; 58(51): 18647-18653, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31609502

RESUMO

All-solid-state batteries have attracted attention owing to the potential high energy density and safety; however, little success has been made on practical applications of solid-state batteries, which is largely attributed to the solid-solid interface issues. A fundamental elucidation of electrode-electrolyte interface behaviors is of crucial significance but has proven difficult. The interfacial resistance and capacity fading issues in a solid-state battery were probed, revealing a heterogeneous phase transition evolution at solid-solid interfaces. The strain-induced interfacial change and the contact loss, as well as a dense metallic surface phase, deteriorate the electrochemical reaction in solid-state batteries. Furthermore, the in situ growth of electrolytes on secondary particles is proposed to fabricate robust solid-solid interface. Our study enlightens new insights into the mechanism behind solid-solid interfacial reaction for optimizing advanced solid-state batteries.

18.
ACS Appl Mater Interfaces ; 11(44): 41258-41266, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31603640

RESUMO

The nitrogen coordinated single cobalt atoms embedded in carbon matrix, i.e., Co/N/C material, is cost-efficient and free from iron-ion induced Fenton reagent, which has been thus considered as a promising candidate to replace the well-accepted Pt-based and Fe/N/C materials for oxygen reduction reaction (ORR). Recently, the pyrolysis of metal-organic framework (MOF) precursors has been investigated to achieve well-defined Co/N/C catalysts with high ORR activity. However, the relationships among the composition/structure of MOF precursor, the derived catalysts, and ORR performance have been rarely touched in specialty, while the regulations to achieve single-atom Co/N/C catalysts derived from MOF are confusing. Herein, we engineer several Co-doped MOF (zeolitic imidazolate frameworks, to be specific) precursors with different compositions and structures by tuning synthesis protocols (e.g., ratios, cobalt sources, and reaction time) and investigate the derived catalysts and their ORR properties. The regulations to single-atom Co/N/C are revealed in this work. The superior ORR activity and durability of the optimized Co/N/C catalysts are revealed and attributed to the well-defined Co-Nx moieties and their stable nanostructures.

19.
Adv Sci (Weinh) ; 5(10): 1800782, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30356990

RESUMO

Due to the abundant and low-cost K resources, the exploration of suitable materials for potassium-ion batteries (KIBs) is advancing as a promising alternative to lithium-ion batteries. However, the large-sized and sluggish-kinetic K ions cause poor battery behavior. This work reports a metallic octahedral CoSe2 threaded by N-doped carbon nanotubes as a flexible framework for a high-performance KIBs anode. The metallic property of CoSe2 together with the highly conductive N-doped carbon nanotubes greatly accelerates the electron transfer and improves the rate performance. The carbon nanotube framework serves as a backbone to inhibit the agglomeration, anchor the active materials, and stabilize the integral structure. Every octahedral CoSe2 particle arranges along the carbon nanotubes in sequence, and the zigzag void space can accommodate the volume expansion during cycling, therefore boosting the cycling stability. Density functional theory is also employed to study the K-ion intercalation/deintercalation process. This unique structure delivers a high capacity (253 mAh g-1 at 0.2 A g-1 over 100 cycles) and enhanced rate performance (173 mAh g-1 at 2.0 A g-1 over 600 cycles) as an advanced anode material for KIBs.

20.
ACS Appl Mater Interfaces ; 10(35): 29638-29646, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30091890

RESUMO

Freely deformable and free-standing electrodes together with high capacity are crucial to realizing flexible Li-ion batteries. Herein, a lamellar graphene/nanocellulose/silicon (GN/NC/Si) film assembled by interpenetrated GN nanosheets is synthesized via a facile vacuum-assisted filtration approach accompanied by the covalent cross-linking effect of glutaraldehyde. The hybrid film consists of the highly conductive GN matrix as an effective current collector, hydroxylated silicon nanoparticles (Si NPs) embedded uniformly within GN interlayer and NC as adhesive to cross-link GN and Si NPs. When applied as anode, the GN/NC/Si film exhibits a high reversible capacity of 1251 mA h g-1 at 100 mA g-1 after 100 cycles and superior rate capability. More importantly, in the stress-strain test, this film represents robust mechanical strength, which not only provides good flexibility but also accommodates volume change of Si during cycling. By coupling with lithium cobalt oxide as the cathode, the full cell successfully powers a light-emitting diode, even bended and folded, indicating the deformation-tolerant GN/NC/Si film electrode for flexible Li-ion batteries. Therefore, the design of layered nanocomposites will offer the possibility closer to the application of flexible batteries.

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