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1.
Materials (Basel) ; 16(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36676390

RESUMO

Mullite-cordierite ceramic saggar is a necessary consumable material used in the synthesis process of LiCoO2 that is easily eroded during application. In our study, we systematically investigated the characteristics and surface corrosion behavior of waste saggar samples. We divided the cross sections of waste saggar into the attached layer, hardened layer, permeability layer, and matrix layer. Then, we examined the high-temperature solid-state reactions between saggar powder and lithium carbonate or cobalt oxide to identify erosion reactants correlating with an increase in the number of recycled saggars. The results of time-of-flight secondary ion mass spectrometric analysis (TOF-SIMS) prove that the maximum erosion penetration of lithium can reach 2 mm. However, our morphology and elemental distribution analysis results show that the erosion penetration of cobalt was only 200 µm. When enough lithium carbonate reacted, lithium aluminate and lithium silicate were the main phases. Our X-ray computed tomography (X-ray CT) analysis results show that the change in phase volume before and after the reaction, including the generation of oxygen and carbon dioxide gas, led to the internal crack expansion of the material-saggar interface. Our results can contribute to improving saggar and upgrading waste saggar utilization technology.

2.
Environ Technol ; : 1-42, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36469642

RESUMO

AbstractA sequence of zeolite carriers (Carrier = ZSM-5, Small crystal ZSM-5, MCM-41, SBA-15) were used to support active metals Mn-Ce, which have presented an enormous potential for plasma oxidation of toluene in air. The prepared samples were detected by means of N2 adsorption-desorption, SEM, XPS, H2-TPR, etc. Through the activity evaluation in the Non-thermal Plasma Reactor, we found that the catalysts with different carriers showed distinct degradation activities. The performance of mesoporous supported catalysts was better than that of microporous catalysts, of which MCM-41 performed best. 96.3% of toluene can be decomposed, and 97.3% of degraded toluene converted into final products CO2 completely at the initial concentration of 1000 ppm and SIE of 9 kJ/L. From the results, we can see that the appropriate carrier is conducive to maximizing the efficiency of the active metal, and Mn-Ce/MCM-41 got the best performance in the plasma catalysis for toluene abatement.

3.
Biosens Bioelectron ; 218: 114742, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36201997

RESUMO

The tremendous growth of disposable electrode-based portable devices for point-of-care testing requires mass production of disposable electrodes in a low-cost and sustainable manner. Here, we demonstrate a green route for the conversion of biomass lignin, patterning, and reduction of the lignin-derived graphene electrodes by sequential laser lithography, water lift-off and sodium borohydride (NaBH4) treatment, and their use for electrochemical lactate biosensors. Energy-saving and localized laser lithography converted the aromatic ring-rich lignin into porous laser-induced graphene (LIG). The conductivity and attachment of the LIG to the substrate were optimized in a factorial experiment with laser power and scan speed as variables. Characterization results revealed the conversion of partial heteroatoms (e.g., Na, S, O) into granular inorganic compounds on the LIG surface under laser treatment. Water was used as an eco-friendly solvent for the patterning of the LIG (P-LIG) by a lift-off process, where the inorganic residues and un-reacted lignin were dissolved, exposing the macro-/micro-pores in the P-LIG. NaBH4 induced a reduction of the P-LIG (P-rLIG) resulting in improved electrochemical kinetics with lower charge transfer resistance (27.3 Ω) compared to the LIG (248.1 Ω) and the P-LIG (61.4 Ω). The porous P-rLIG served as a 3D electrode for the deposition of Prussian blue and lactate oxidase for disposable electrochemical lactate biosensors, delivering a good analytical performance towards lactate detection with a linear range up to 16 mM and a high sensitivity (1.21 µA mM-1). These lignin-derived disposable electrodes, utilizing renewable resources together with low-energy consumption fabrication and patterning, may contribute to the sustainable manufacturing of biosensors for point-of-care and point-of-use applications.


Assuntos
Técnicas Biossensoriais , Grafite , Grafite/química , Técnicas Biossensoriais/métodos , Lignina , Eletrodos , Água , Lactatos , Solventes
4.
Environ Res ; 214(Pt 3): 113968, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35964675

RESUMO

Cathode electrocatalyst is quite critical to realize the application of microbial fuel cells (MFCs). Perovskite oxides have been considered as potential MFCs cathode catalysts to replace Pt/C. Herein, Cu-doped perovskite oxide with a stable porous structure and excellent conductivity was successfully prepared through a sol-gel method. Due to the incorporation of Cu, CaFe0.9Cu0.1O3 has more micropores and a larger surface area, which are more conducive to contact with oxygen. Doping Cu resulted in more Fe3+ in B-site and thus enhanced its binding capability to oxygen molecules. The data from electrochemical test demonstrated that the as-prepared catalyst has good conductivity, high stability, and excellent ORR properties. Compared with Pt/C catalyst, CaFe0.9Cu0.1O3 exhibits a lower overpotential, which had an onset potential of 0.195 V and a half-wave potential of -0.224 V, respectively. CaFe0.9Cu0.1O3 displays an outstanding four-electron pathway for ORR mechanism and demonstrates superiors corrosion resistance and stability. The MFC with CaFe0.9Cu0.1O3 has a greater maximum power density (1090 mW m-3) rather than that of Pt/C cathode (970 mW m-3). This work demonstrated CaFe0.9Cu0.1O3 is an economic and efficient cathodic catalyst for MFCs.


Assuntos
Fontes de Energia Bioelétrica , Compostos de Cálcio , Catálise , Eletrodos , Óxidos/química , Oxigênio/química , Titânio
5.
Adv Sci (Weinh) ; 9(30): e2203681, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36031391

RESUMO

Perovskite solar cells (PSCs) suffer from significant nonradiative recombination at perovskite/charge transport layer heterojunction, seriously limiting their power conversion efficiencies. Herein, solution-processed chromium multioxide (CrOx ) is judiciously selected to construct a MAPbI3 /CrOx /Spiro-OMeTAD hole-selective heterojunction. It is demonstrated that the inserted CrOx not only effectively reduces defect sites via redox shuttle at perovskite contact, but also decreases valence band maximum (VBM)-HOMO offset between perovskite and Spiro-OMeTAD. This will diminish thermionic losses for collecting holes and thus promote charge transport across the heterojunction, suppressing both defect-assisted recombination and interface carrier recombination. As a result, a remarkable improvement of 21.21% efficiency with excellent device stability is achieved compared to 18.46% of the control device, which is among the highest efficiencies for polycrystalline MAPbI3 based n-i-p planar PSCs reported to date. These findings of this work provide new insights into novel charge-selective heterojunctions for further enhancing efficiency and stability of PSCs.

6.
Macromolecules ; 55(16): 7294-7302, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36034325

RESUMO

Ladder-type conjugated polymers exhibit a remarkable performance in (opto)electronic devices. Their double-stranded planar structure promotes an extended π-conjugation compared to inter-ring-twisted analogues, providing an excellent basis for exploring the effects of charge localization on polaron formation. Here, we investigated alkali-metal n-doping of the ladder-type conjugated polymer (polybenzimidazobenzophenanthroline) (BBL) through detailed in situ spectroscopic and electrical characterizations. Photoelectron spectroscopy and ultraviolet-visible-near-infrared (UV-vis-NIR) spectroscopy indicate polaron formation upon potassium (K) doping, which agrees well with theoretical predictions. The semiladder BBB displays a similar evolution in the valence band with the appearance of two new features below the Fermi level upon K-doping. Compared to BBL, distinct differences appear in the UV-vis-NIR spectra due to more localized polaronic states in BBB. The high conductivity (2 S cm-1) and low activation energy (44 meV) measured for K-doped BBL suggest disorder-free polaron transport. An even higher conductivity (37 S cm-1) is obtained by changing the dopant from K to lithium (Li). We attribute the enhanced conductivity to a decreased perturbation of the polymer nanostructure induced by the smaller Li ions. These results highlight the importance of polymer chain planarity and dopant size for the polaronic state in conjugated polymers.

7.
J Colloid Interface Sci ; 628(Pt A): 652-662, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940149

RESUMO

Air cathode microbial fuel cell (AC-MFC) cannot be used on a large scale because of its low oxygen reduction reaction (ORR) efficiency. Despite the fact that bimetallic catalysts can greatly enhance the oxygen reduction rate by regulating the electronic structure of the active site, the flaws of insufficient exposure of the active site and easy metal agglomeration limit its catalytic activity. Herein, we report on the preparation of a stable heteroatomic substrate using a copper material organic framework as a precursor, covered by Fe-based active sites. As a result of dipole-dipole interactions, the reduced product Fe2+ forms a weak Fe-O surface that is conducive to the adsorption of active substances. The presence of Fe0 enhances the electrical conductivity of the catalytic, thus promoting ORR efficiency. Through redox coupling, the D-band center of Fe at FeCu@CN is optimized and brought close to the Fermi level to facilitate electron transfer. Notably, FeCu@CN demonstrates a superior power density of 2796.23 ± 278.58 mW m-3, far exceeding that of Pt/C (1363.93 ± 102.56 mW m-3), in the application of microbial fuel cells (MFCs). Meanwhile, the MFC-loaded FeCu@CN maintains excellent stability and outstanding output voltage after 1000 h, which provides feasibility for large-scale application.


Assuntos
Fontes de Energia Bioelétrica , Carbono/química , Cobre , Eletrodos , Nitrogênio/química , Oxigênio/química
8.
Science ; 377(6605): 495-501, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35901165

RESUMO

Record power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) have been obtained with the organic hole transporter 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenyl-amine)9,9'-spirobifluorene (spiro-OMeTAD). Conventional doping of spiro-OMeTAD with hygroscopic lithium salts and volatile 4-tert-butylpyridine is a time-consuming process and also leads to poor device stability. We developed a new doping strategy for spiro-OMeTAD that avoids post-oxidation by using stable organic radicals as the dopant and ionic salts as the doping modulator (referred to as ion-modulated radical doping). We achieved PCEs of >25% and much-improved device stability under harsh conditions. The radicals provide hole polarons that instantly increase the conductivity and work function (WF), and ionic salts further modulate the WF by affecting the energetics of the hole polarons. This organic semiconductor doping strategy, which decouples conductivity and WF tunability, could inspire further optimization in other optoelectronic devices.

9.
Nat Commun ; 13(1): 2046, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440117

RESUMO

Energy level alignment (ELA) at donor (D) -acceptor (A) heterojunctions is essential for understanding the charge generation and recombination process in organic photovoltaic devices. However, the ELA at the D-A interfaces is largely underdetermined, resulting in debates on the fundamental operating mechanisms of high-efficiency non-fullerene organic solar cells. Here, we systematically investigate ELA and its depth-dependent variation of a range of donor/non-fullerene-acceptor interfaces by fabricating and characterizing D-A quasi bilayers and planar bilayers. In contrast to previous assumptions, we observe significant vacuum level (VL) shifts existing at the D-A interfaces, which are demonstrated to be abrupt, extending over only 1-2 layers at the heterojunctions, and are attributed to interface dipoles induced by D-A electrostatic potential differences. The VL shifts result in reduced interfacial energetic offsets and increased charge transfer (CT) state energies which reconcile the conflicting observations of large energy level offsets inferred from neat films and large CT energies of donor - non-fullerene-acceptor systems.

11.
J Cataract Refract Surg ; 48(2): 238-244, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34538778

RESUMO

This study aimed to evaluate the impact of Nd:YAG laser capsulotomy on the incidence of pseudophakic retinal detachment (RD). The PubMed and Embase databases were searched for meta-analysis. Subgroup analyses were conducted according to study location, number of cases, mean follow-up time, and cataract procedure. The final analysis included 11 studies with 309 cases of RD in 65 117 eyes undergoing cataract surgery. Among them, 8232 eyes underwent Nd:YAG capsulotomy. This analysis demonstrated an increased risk for RD with Nd:YAG laser capsulotomy (relative risk [RR], 1.57; 95% CI, 1.17-2.12; P = .003; hazard ratio, 1.64; 95% CI, 1.03-2.62; P = .04). Subgroup analysis suggested somewhat stronger associations in Asian (RR, 4.54; 95% CI, 2.20-9.38; P < .0001) than in non-Asian populations (Americans, P = .12; Europeans and others, P = .21) and with extracapsular cataract extraction (RR, 2.97; 95% CI, 1.83-4.83; P < .0001) than with phacoemulsification (P = .95). To conclude, Nd:YAG laser capsulotomy may be associated with an increased risk for pseudophakic RD.


Assuntos
Opacificação da Cápsula , Extração de Catarata , Terapia a Laser , Lasers de Estado Sólido , Cápsula do Cristalino , Descolamento Retiniano , Opacificação da Cápsula/etiologia , Opacificação da Cápsula/cirurgia , Humanos , Lasers de Estado Sólido/uso terapêutico , Cápsula do Cristalino/cirurgia , Complicações Pós-Operatórias/cirurgia , Descolamento Retiniano/etiologia , Descolamento Retiniano/cirurgia
12.
Environ Res ; 200: 111736, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34310968

RESUMO

Photocatalysis coupled with sulfate radical-based advanced oxidation process (SR-AOPs) is an efficient strategy to enhance the degradation efficiency of organic pollution. Herein, a Z-scheme CuFe2O4/MnO2 composite catalyst was successfully fabricated by the hydrothermal method. A series of characterizations demonstrated that the higher CuFe2O4 particle dispersion and larger BET surface area of CuFe2O4/MnO2 catalyst contributed to a high catalytic activity toward the phenol removal compared with pure CuFe2O4. The effects of catalyst concentration, pH, and peroxymonosulfate (PMS) concentration were studied according to the Box-Behnken Design (BBD) method. The results indicated that 100 mg/L 100 mL phenol could be degraded completely at 0.5 g/L CuFe2O4/MnO2 catalyst, pH = 4.8 and 0.5 mM PMS within 30 min. Moreover, the excellent reusability and stability of CuFe2O4/MnO2 were indicated by the results of recycling degradation and ion leaching test. The free radical quenching experiments and electron spin resonance (ESR) confirmed that h+, SO4•-, and •OH were the main reaction species for phenol oxidation. Based on the results of gas chromatography-mass spectrometry (GC-MS) and ion chromatography, the degradation pathway of phenol was proposed, and the toxicity of phenol degradation intermediates was evaluated. This work may provide new insights into the design of heterojunction photocatalysts for PMS activation to remove organic pollutants.


Assuntos
Compostos de Manganês , Óxidos , Peróxidos , Fenóis
13.
Nat Commun ; 12(1): 2354, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883549

RESUMO

Conducting polymers, such as the p-doped poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), have enabled the development of an array of opto- and bio-electronics devices. However, to make these technologies truly pervasive, stable and easily processable, n-doped conducting polymers are also needed. Despite major efforts, no n-type equivalents to the benchmark PEDOT:PSS exist to date. Here, we report on the development of poly(benzimidazobenzophenanthroline):poly(ethyleneimine) (BBL:PEI) as an ethanol-based n-type conductive ink. BBL:PEI thin films yield an n-type electrical conductivity reaching 8 S cm-1, along with excellent thermal, ambient, and solvent stability. This printable n-type mixed ion-electron conductor has several technological implications for realizing high-performance organic electronic devices, as demonstrated for organic thermoelectric generators with record high power output and n-type organic electrochemical transistors with a unique depletion mode of operation. BBL:PEI inks hold promise for the development of next-generation bioelectronics and wearable devices, in particular targeting novel functionality, efficiency, and power performance.

14.
J Phys Chem Lett ; 12(15): 3773-3778, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33844910

RESUMO

The conduction band dispersion in methylammonium lead iodide (CH3NH3PbI3) was studied by both angle-resolved two-photon photoelectron spectroscopy (AR-2PPE) with low photon intensity (∼0.0125 nJ/pulse) and angle-resolved low-energy inverse photoelectron spectroscopy (AR-LEIPS). Clear energy dispersion of the conduction band along the Γ-M direction was first observed by these independent methods under different temperatures, and the dispersion was found to be consistent with band calculation under the cubic phase. The effective mass of the electrons at the Γ point was estimated to be (0.20 ± 0.05)m0 at the temperature of 90 K. The observed conduction band energy was different between the AR-LEIPS and AR-2PPE, which was ascribed to the electronic-correlation-dependent difference of initial and final states probing processes. The present results also indicate that the surface structure in CH3NH3PbI3 provides the cubic-dominated electronic property even at lower temperatures.

15.
ACS Appl Mater Interfaces ; 13(39): 47218-47225, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34551513

RESUMO

Interface dipoles formed at an electrolyte/electrode interface have been widely studied and interpreted using the "double dipole step" model, where the dipole vector is determined by the size and/or range of motion of the charged ions. Some electron transport materials (ETMs) with lone pairs of electrons on heteroatoms exhibit a similar interfacial behavior. However, the origin of the dipoles in such materials has not yet been explored in great depth. Herein, we systematically investigate the influence of the lone pair of electrons on the interface dipole through three pyridine derivatives B2-B4PyMPM. Experiments show that different positions of nitrogen atoms in the three materials give rise to different hydrogen bonds and molecular orientations, thereby affecting the areal density and direction of the lone pair of electrons. The interface dipoles of the three materials predicted by the "double dipole step" model are in good agreement with the ultraviolet photoelectron spectroscopy results both in spin-coated and vacuum-deposited films. These findings help to better understand the ETMs/electrode interfacial behaviors and provide new guidelines for the molecular design of the interlayer.

16.
Virol Sin ; 36(2): 264-272, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32894405

RESUMO

On entering sensory ganglia, herpes simplex viruses 1 (HSV-1) establishes a latent infection with the synthesis of a latency associated transcript (LAT) or initiates productive infection with expression of a set of immediate early viral proteins. The precise mechanisms how expression of α genes is suppressed during the latency are unknown. One mechanism that has been proposed is illustrated in the case of ICP0, a key immediate early viral regulatory protein. Specifically, the 2 kb LAT intron is complementary to the 3' terminal portion of ICP0 mRNA. To test the hypothesis that accumulation of LAT negatively affects the accumulation of ICP0 mRNA, we inserted a DNA fragment encoding two poly(A) sequences into LAT to early terminate LAT transcript without interrupting the complementary sequence of ICP0 transcript (named as SR1603). Comparisons of the parent (SR1601) and mutant (SR1603) HSV-1 viruses showed the following: Neurons harboring latent SR1603 virus accumulated equivalent amounts of viral DNA but higher amounts of ICP0 mRNA and lower amounts of LAT, when compared to neurons harboring the SR1601 virus. One notable difference between the two viruses is that viral RNA accumulation in explanted ganglia harboring SR1603 virus initiated significantly sooner than that in neurons harboring SR1601 virus, suggesting that ICP0 may act as an activator of viral gene expression in permissive cells. Collectively, these data suggest that increased ICP0 mRNA by suppressed LAT did not affect the establishment of latency in latently infected murine ganglia.


Assuntos
Herpesvirus Humano 1 , Animais , Feminino , Gânglios , Herpesvirus Humano 1/genética , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/genética , Ubiquitina-Proteína Ligases/genética , Latência Viral
17.
Adv Mater ; 32(34): e2002344, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32686255

RESUMO

Ternary architecture is one of the most effective strategies to boost the power conversion efficiency (PCE) of organic solar cells (OSCs). Here, an OSC with a ternary architecture featuring a highly crystalline molecular donor DRTB-T-C4 as a third component to the host binary system consisting of a polymer donor PM6 and a nonfullerene acceptor Y6 is reported. The third component is used to achieve enhanced and balanced charge transport, contributing to an improved fill factor (FF) of 0.813 and yielding an impressive PCE of 17.13%. The heterojunctions are designed using so-called pinning energies to promote exciton separation and reduce recombination loss. In addition, the preferential location of DRTB-T-C4 at the interface between PM6 and Y6 plays an important role in optimizing the morphology of the active layer.

18.
ACS Appl Mater Interfaces ; 12(22): 24965-24970, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32394700

RESUMO

Quasi-two-dimensional (Q-2D) perovskites featured with multidimensional quantum wells (QWs) have been the main candidates for optoelectronic applications. However, excessive low-dimensional perovskites are unfavorable to the device efficiency due to the phonon-exciton interaction and the inclusion of insulating large organic cations. Herein, the formation of low-dimensional QWs is suppressed by removing the organic cation 1-naphthylmethylamine iodide (NMAI) through ultrahigh vacuum (UHV) annealing. Perovskite light-emitting diode (PLED) devices based on films annealed with optimized UHV conditions show a higher external quantum efficiency (EQE) of 13.0% and wall-plug efficiency of 11.1% compared to otherwise identical devices with films annealed in a glovebox.

20.
Nat Mater ; 19(7): 738-744, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32152564

RESUMO

Doping of organic semiconductors is crucial for the operation of organic (opto)electronic and electrochemical devices. Typically, this is achieved by adding heterogeneous dopant molecules to the polymer bulk, often resulting in poor stability and performance due to dopant sublimation or aggregation. In small-molecule donor-acceptor systems, charge transfer can yield high and stable electrical conductivities, an approach not yet explored in all-conjugated polymer systems. Here, we report ground-state electron transfer in all-polymer donor-acceptor heterojunctions. Combining low-ionization-energy polymers with high-electron-affinity counterparts yields conducting interfaces with resistivity values five to six orders of magnitude lower than the separate single-layer polymers. The large decrease in resistivity originates from two parallel quasi-two-dimensional electron and hole distributions reaching a concentration of ∼1013 cm-2. Furthermore, we transfer the concept to three-dimensional bulk heterojunctions, displaying exceptional thermal stability due to the absence of molecular dopants. Our findings hold promise for electro-active composites of potential use in, for example, thermoelectrics and wearable electronics.

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