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1.
Cell ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38959890

RESUMO

Hypothalamic neural circuits regulate instinctive behaviors such as food seeking, the fight/flight response, socialization, and maternal care. Here, we identified microdeletions on chromosome Xq23 disrupting the brain-expressed transient receptor potential (TRP) channel 5 (TRPC5). This family of channels detects sensory stimuli and converts them into electrical signals interpretable by the brain. Male TRPC5 deletion carriers exhibited food seeking, obesity, anxiety, and autism, which were recapitulated in knockin male mice harboring a human loss-of-function TRPC5 mutation. Women carrying TRPC5 deletions had severe postpartum depression. As mothers, female knockin mice exhibited anhedonia and depression-like behavior with impaired care of offspring. Deletion of Trpc5 from oxytocin neurons in the hypothalamic paraventricular nucleus caused obesity in both sexes and postpartum depressive behavior in females, while Trpc5 overexpression in oxytocin neurons in knock-in mice reversed these phenotypes. We demonstrate that TRPC5 plays a pivotal role in mediating innate human behaviors fundamental to survival, including food seeking and maternal care.

2.
Brain ; 147(7): 2507-2521, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577773

RESUMO

Opioid pain medications, such as morphine, remain the mainstay for treating severe and chronic pain. Prolonged morphine use, however, triggers analgesic tolerance and hyperalgesia (OIH), which can last for a long period after morphine withdrawal. How morphine induces these detrimental side effects remains unclear. Here, we show that morphine tolerance and OIH are mediated by Tiam1-coordinated synaptic structural and functional plasticity in the spinal nociceptive network. Tiam1 is a Rac1 GTPase guanine nucleotide exchange factor that promotes excitatory synaptogenesis by modulating actin cytoskeletal dynamics. We found that prolonged morphine treatment activated Tiam1 in the spinal dorsal horn and Tiam1 ablation from spinal neurons eliminated morphine antinociceptive tolerance and OIH. At the same time, the pharmacological blockade of Tiam1-Rac1 signalling prevented the development and reserved the established tolerance and OIH. Prolonged morphine treatment increased dendritic spine density and synaptic NMDA receptor activity in spinal dorsal horn neurons, both of which required Tiam1. Furthermore, co-administration of the Tiam1 signalling inhibitor NSC23766 was sufficient to abrogate morphine tolerance in chronic pain management. These findings identify Tiam1-mediated maladaptive plasticity in the spinal nociceptive network as an underlying cause for the development and maintenance of morphine tolerance and OIH and provide a promising therapeutic target to reduce tolerance and prolong morphine use in chronic pain management.


Assuntos
Analgésicos Opioides , Tolerância a Medicamentos , Hiperalgesia , Morfina , Plasticidade Neuronal , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T , Animais , Morfina/farmacologia , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/metabolismo , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Tolerância a Medicamentos/fisiologia , Camundongos , Analgésicos Opioides/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Células do Corno Posterior/efeitos dos fármacos , Células do Corno Posterior/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
3.
Nucleic Acids Res ; 51(2): 501-516, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35929025

RESUMO

Individual cells are basic units of life. Despite extensive efforts to characterize the cellular heterogeneity of different organisms, cross-species comparisons of landscape dynamics have not been achieved. Here, we applied single-cell RNA sequencing (scRNA-seq) to map organism-level cell landscapes at multiple life stages for mice, zebrafish and Drosophila. By integrating the comprehensive dataset of > 2.6 million single cells, we constructed a cross-species cell landscape and identified signatures and common pathways that changed throughout the life span. We identified structural inflammation and mitochondrial dysfunction as the most common hallmarks of organism aging, and found that pharmacological activation of mitochondrial metabolism alleviated aging phenotypes in mice. The cross-species cell landscape with other published datasets were stored in an integrated online portal-Cell Landscape. Our work provides a valuable resource for studying lineage development, maturation and aging.


How many cell types are there in nature? How do they change during the life cycle? These are two fundamental questions that researchers have been trying to understand in the area of biology. In this study, single-cell mRNA sequencing data were used to profile over 2.6 million individual cells from mice, zebrafish and Drosophila at different life stages, 1.3 million of which were newly collected. The comprehensive datasets allow investigators to construct a cross-species cell landscape that helps to reveal the conservation and diversity of cell taxonomies at genetic and regulatory levels. The resources in this study are assembled into a publicly available website at http://bis.zju.edu.cn/cellatlas/.


Assuntos
Análise de Célula Única , Animais , Camundongos , Análise de Sequência de RNA , Peixe-Zebra/crescimento & desenvolvimento , Drosophila/crescimento & desenvolvimento
4.
Small ; 20(7): e2307619, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803332

RESUMO

Atomically precise metal nanoclusters (NCs) have garnered tremendous attention as light-harvesting antennas in heterogeneous photocatalysis due to unique atomic stacking mode, quantum confinement effect, and enriched active sites. However, metal NCs as photosensitizers suffer from extremely short carrier lifetime, poor photostability, and difficulty in carrier migration, which hinder the wide-spread utilization of metal NCs in solar energy conversion. To solve these problems, herein, Ag-doped glutathione (GSH)-capped gold NCs, i.e., alloy Au1- x Agx @GSH NCs and non-conjugated insulating polymer of poly(diallyl-dimethylammonium chloride) (PDDA) are utilized as the building blocks for layer-by-layer assembly of spatially multilayered alloy NCs/metal oxide (MO) photosystems. The alternately deposited ultrathin PDDA layer in-between Au1- x Agx @GSH NCs on the MO substrate functions as an efficient charge flow mediator to relay the directional photoelectron transfer over Au1- x Agx @GSH NCs, giving rise to the cascade charge transfer chain. This peculiar carrier migration mode endowed by exquisite interface configuration design significantly boosts the unidirectional electron migration from the Au1- x Agx @GSH NCs to the MO substrate, substantially improving the visible-light-driven photoelectrochemical water oxidation performances of MO/(PDDA-Au1- x Agx )n multilayer heterostructured photoanodes. The work will inspire the rational construction of alloy metal NCs-based photosystems for modulating spatially controllable charge transfer pathway for solar energy conversion.

5.
Small ; : e2400958, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644328

RESUMO

Quantum dots (QDs) colloidal nanocrystals are attracting enduring interest by scientific communities for solar energy conversion due to generic physicochemical merits including substantial light absorption coefficient, quantum confinement effect, enriched catalytically active sites, and tunable electronic structure. However, photo-induced charge carriers of QDs suffer from ultra-short charge lifespan and poor stability, rendering controllable vectorial charge modulation and customizing robust and stable QDs artificial photosystems challenging. Herein, tailor-made oppositely charged transition metal chalcogenides quantum dots (TMCs QDs) and MXene quantum dots (MQDs) are judiciously harnessed as the building blocks for electrostatic layer-by-layer assembly buildup on the metal oxides (MOs) framework. In these exquisitely designed LbL assembles MOs/(TMCs QDs/MQDs)n heterostructured photoanodes, TMCs QDs layer acts as light-harvesting antennas, and MQDs layer serves as electron-capturing mediator to relay cascade electrons from TMCs QDs to the MOs substrate, thereby yielding the spatially ordered tandem charge transport chain and contributing to the significantly boosted charge separation over TMCs QDs and solar water oxidation efficiency of MOs/(TMCs QDs/MQDs)n photoanodes. The relationship between interface configuration and charge transfer characteristics is unambiguously unlocked, by which photoelectrochemical mechanism is elucidated. This work would provide inspiring ideas for precisely mediating interfacial charge transfer pathways over QDs toward solar energy conversion.

6.
Chemistry ; : e202401369, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39003675

RESUMO

A visible-light-initiated energy-transfer enabled radical cyclization for the divergent synthesis of polycyclic γ-sultine derivatives has been developed. The reaction provides an alternative and expeditious access to benzofused γ-sultine frameworks, the analogues of γ-lactones and γ-sultones, and features good functional group compatibility, mild reaction conditions and excellent diastereoselectivity. The robustness and application potential of this method have also been successfully displayed by two gram-scale reactions and the synthesis of polycyclic sultones. Mechanistic studies indicated the transformations through a possible energy-transfer enabled intramolecular radical homolytic substitution or hydrogen atom transfer process mainly.

7.
Mol Psychiatry ; 28(3): 1365-1382, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36473997

RESUMO

Chronic stress exposure induces maladaptive behavioral responses and increases susceptibility to neuropsychiatric conditions. However, specific neuronal populations and circuits that are highly sensitive to stress and trigger maladaptive behavioral responses remain to be identified. Here we investigate the patterns of spontaneous activity of proopiomelanocortin (POMC) neurons in the arcuate nucleus (ARC) of the hypothalamus following exposure to chronic unpredictable stress (CUS) for 10 days, a stress paradigm used to induce behavioral deficits such as anhedonia and behavioral despair [1, 2]. CUS exposure increased spontaneous firing of POMC neurons in both male and female mice, attributable to reduced GABA-mediated synaptic inhibition and increased intrinsic neuronal excitability. While acute activation of POMC neurons failed to induce behavioral changes in non-stressed mice of both sexes, subacute (3 days) and chronic (10 days) repeated activation of POMC neurons was sufficient to induce anhedonia and behavioral despair in males but not females under non-stress conditions. Acute activation of POMC neurons promoted susceptibility to subthreshold unpredictable stress in both male and female mice. Conversely, acute inhibition of POMC neurons was sufficient to reverse CUS-induced anhedonia and behavioral despair in both sexes. Collectively, these results indicate that chronic stress induces both synaptic and intrinsic plasticity of POMC neurons, leading to neuronal hyperactivity. Our findings suggest that POMC neuron dysfunction drives chronic stress-related behavioral deficits.


Assuntos
Anedonia , Núcleo Arqueado do Hipotálamo , Depressão , Neurônios , Pró-Opiomelanocortina , Estresse Psicológico , Animais , Feminino , Masculino , Camundongos , Doença Aguda , Anedonia/fisiologia , Núcleo Arqueado do Hipotálamo/metabolismo , Núcleo Arqueado do Hipotálamo/fisiopatologia , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Doença Crônica , Excitabilidade Cortical/fisiologia , Depressão/metabolismo , Depressão/fisiopatologia , Modelos Animais de Doenças , Transtornos Mentais/metabolismo , Transtornos Mentais/fisiopatologia , Camundongos Endogâmicos C57BL , Fenômenos Fisiológicos do Sistema Nervoso , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Pró-Opiomelanocortina/biossíntese , Pró-Opiomelanocortina/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Sinapses/metabolismo , Sinapses/fisiologia
8.
Langmuir ; 40(17): 9144-9154, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38629776

RESUMO

Wastewater pollutants are a major threat to natural resources, with antibiotics and heavy metals being common water contaminants. By harnessing clean, renewable solar energy, photocatalysis facilitates the synergistic removal of heavy metals and antibiotics. In this paper, MXene was both a template and raw material, and MXene-derived oxide (TiO2) and SnIn4S8 Z-scheme composite materials were synthesized and characterized. The synergistic mode of photocatalytic reduction and oxidation leads to the enhanced utilization of e-/h+ pairs. The TiO2/SnIn4S8 exhibited a higher photocatalytic capacity for the simultaneous removal of tetracycline (TC) (20 mg·L-1) and Cr(VI) (15 mg·L-1). The main active substances of TC degradation and Cr(VI) reduction were identified via free radical scavengers and electron paramagnetic resonance (EPR). Additionally, the potential photocatalytic degradation route of TC was thoroughly elucidated through liquid chromatography-mass spectrometry (LC-MS).

9.
Inorg Chem ; 63(2): 1471-1479, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38173240

RESUMO

Atomically precise metal nanoclusters (NCs) have been deemed as a new generation of metal nanomaterials because of their characteristic atomic stacking fashion, quantum confinement effect, and multitude of active sites. The discrete molecular-like energy band structure of metal NCs endows them with photosensitization capability for light harvesting and conversion. However, applications of metal NCs in photoelectrocatalysis are limited by the ultrafast charge recombination and unfavorable stability, impeding the construction of metal NC-based photosystems. In this work, we elaborately crafted multilayered metal oxide (MO)/(metal NCs/insulating polymer)n photoanodes by a facile layer-by-layer (LbL) assembly technique. In these well-defined heterostructured photoanodes, glutathione (GSH)-wrapped metal NCs (Agx@GSH, Ag9@GSH6, Ag16@GSH9, and Ag31@GSH19) and an insulating poly(allylamine hydrochloride) (PAH) layer are alternately deposited on the MO substrate in a highly ordered integration mode. We found that photoelectrons of metal NCs can be tunneled into the MO substrate via the intermediate ultrathin insulating polymer layer by stimulating the tandem charge transfer route, thus facilitating charge separation and boosting photoelectrochemical water oxidation performances. Our work would open a new frontier for judiciously regulating directional charge transport over atomically precise metal NCs for solar-to-hydrogen conversion.

10.
Inorg Chem ; 63(19): 8970-8976, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38693870

RESUMO

Wholly distinct from conjugated polymers which are featured by generic charge transfer capability stemming from a conjugated molecular structure, solid nonconjugated polymers mediated charge transport has long been deemed as theoretically impossible because of the deficiency of π electrons along the molecular skeleton, thereby retarding their widespread applications in solar energy conversion. Herein, we first conceptually unveil that intact encapsulation of metal oxides (e.g., TiO2, WO3, Fe2O3, and ZnO) with an ultrathin nonconjugated polyelectrolyte of branched polyethylenimine (BPEI) can unexpectedly accelerate the unidirectional charge transfer to the active sites and foster the defect generation, which contributes to the boosted charge separation and prolonged charge lifetime, ultimately resulting in considerably improved photoelectrochemical (PEC) water oxidation activities. The interfacial charge transport origins endowed by BPEI adornment are elucidated, which include acting as a hole-withdrawing mediator, promoting vacancy generation, and stimulating the directional charge flow route. We additionally ascertain that such charge transport characteristics of BPEI are universal. This work would unlock the charge transfer capability of nonconjugated polymers for solar water oxidation. The nonconjugated insulating polymer was utilized as a charge transport mediator for boosting charge migration and separation over metal oxides toward solar water oxidation.

11.
Inorg Chem ; 63(1): 870-880, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38117690

RESUMO

Solar-powered photocatalytic conversion of CO2 to hydrocarbon fuels represents an emerging approach to solving the greenhouse effect. However, low charge separation efficiency, deficiency of surface catalytic active sites, and sluggish charge-transfer kinetics, together with the complicated reaction pathway, concurrently hinder the CO2 reduction. Herein, we show the rational construction of transition metal chalcogenides (TMCs) heterostructure CO2 reduction photosystems, wherein the TMC substrate is tightly integrated with amorphous oxygen-containing cobalt sulfide (CoSOH) by a solid non-conjugated polymer, i.e., poly(vinyl alcohol) (PVA), to customize the unidirectional charge-transfer pathway. In this well-defined multilayered nanoarchitecture, the PVA interim layer intercalated between TMCs and CoSOH acts as a hole-relaying mediator and meanwhile boosts CO2 adsorption capacity, while CoSOH functions as a terminal hole-collecting reservoir, stimulating the charge transport kinetics and boosting the charge separation over TMCs. This peculiar interface configuration and charge transport characteristics endow TMC/PVA/CoSOH heterostructures with significantly enhanced visible-light-driven photoactivity and CO2 conversion. Based on the intermediates probed during the photocatalytic CO2 reduction reaction, the photocatalytic mechanism was determined. Our work would inspire sparkling ideas to mediate the charge transfer over semiconductor for solar carbon neutral conversion.

12.
Inorg Chem ; 63(24): 11092-11101, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38843593

RESUMO

Black phosphorus (BP), a promising two-dimensional (2D) layered semiconductor material, has gained enormous attention due to its impressive properties over the past several years. Although plenty of methods have been developed to synthesize high-quality BP, most of the currently available BP materials still suffer from unsatisfactory crystallization, purity, and stability in air, hindering their practical application. A facile approach to synthesizing ultrahigh-quality single-crystal BP is of significance to shed light on the nature of 2D semiconductor materials and their massive application. In this work, we present the facile and efficient circulating vapor growth approach to growing bulk single-crystal BP. The as-grown BP material features high crystallinity and ultrahigh purity (higher than 99.999 at %), exceeding those of all the previously reported and some commercially available BP crystals. It also maintains excellent stability in air and water after 15 consecutive days of test. Moreover, the as-synthesized BP material features good thermal stability, oxidation resistance, and excellent electrical properties, as well. This study provides a new approach for the fabrication of ultrahigh-quality BP material and thus promotes its application.

13.
Molecules ; 29(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38893422

RESUMO

Currently, new clean energy storage technology must be effective, affordable, and ecologically friendly so as to meet the diverse and sustainable needs of the energy supply. In this work, NiCo-LDH containing intercalated EG was successfully prepared within 210 s using an ultrafast microwave radiation technique. Subsequently, a series of characterization and systematic electrochemical tests were conducted to analyze the composition, structure, and energy storage mechanism of the NiCo-LDH material. The Ni:Co ratio of 5:5 results in the highest capacitance value of 2156 F/g at 1 A/g and an outstanding rate performance of 86.8% capacity retention rate at 10 A/g. The results demonstrated that the unique porous structure of NiCo-LDH and large layer spacing were conducive to more electrochemical reactions. Additionally, an electrochemical test was carried out on the NiCo-LDH as a hybrid supercapacitor electrode material, with NiCo-LDH-5:5 serving as the positive electrode and activated carbon as the negative electrode, the asymmetric supercapacitor can achieve a maximum energy density of 82.5 Wh kg-1 and power density of 8000 W kg-1. The NiCo-LDH-5:5//AC hybrid supercapacitors own 81.5% cycle stability and 100% coulombic efficiency after 6000 cycles at 10 A/g.

14.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257333

RESUMO

In this work, a series of urchin-like Ce(HCOO)3 nanoclusters were synthesized via a facile and scalable microwave-assisted method by varying the irradiation time, and the structure-property relationship was investigated. The optimization of the reaction time was performed based on structural characterizations and electrochemical performances, and the Ce(HCOO)3-210 s sample shows a specific capacitance as high as 132 F g-1 at a current density of 1 A g-1. This is due to the optimal mesoporous hierarchical structure and crystallinity that are beneficial to its conductivity, offering abundant Ce3+/Ce4+ active sites and facilitating the transportation of electrolyte ions. Moreover, an asymmetric supercapacitor based on Ce(HCOO)3//AC was fabricated, which delivers a maximum energy density of 14.78 Wh kg-1 and a considerably high power density of 15,168 W kg-1. After 10,000 continuous charge-discharge cycles at 3 A g-1, the ASC device retains 81.3% of its initial specific capacitance. The excellent comprehensive electrochemical performance of this urchin-like Ce(HCOO)3 offers significant promise for practical supercapacitor applications.

15.
Int Wound J ; 21(3): e14768, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38446012

RESUMO

Colorectal cancer is a common malignant digestive tract tumour with high morbidity and mortality. Early detection, treatment and diagnosis are crucial for preventing and treating colorectal cancer, which develops through multi-stage accumulation and gene participation, affecting tumour marker levels. Chronic wounds can lead to the development of certain cancers, such as colorectal cancer. The prolonged inflammation and tissue repair caused by chronic wounds can trigger cellular changes, potentially promoting cancerous cell growth in the colon. The formation and progression of colorectal cancer involve changes in tumour markers, such as carcinoembryonic antigen (CEA), sugar chain antigen 19-9 (CA199) and CA125. This study explores the clinical application value of a stool routine combined with serum tumour marker detection in diagnosing colorectal cancer. The experiment team examined the clinical information of 56 colorectal cancer patients alongside a control group of 56 healthy patients. Distinct stool characteristics and heightened occult blood rates were evident in colorectal cancer cases. The combined approach integrating stool routine and serum tumour markers improved diagnostic accuracy, displaying enhanced sensitivity and specificity compared with individual markers or stool routines alone. Bioinformatics analysis indicated increased CEA and CA125 levels in colorectal cancer tissues versus normal tissues, hinting at potential prognostic implications. Exploring wound-healing genes like Vascular Endothelial Growth Factor A (VEGFA), Tumour Protein 53 (TP53) and Transforming Growth Factor Alpha (TGFA) revealed heightened expression in colorectal cancer, suggesting their potential role in disease progression. These markers showed associations with various immune cell types, suggesting their impact within the tumour microenvironment (p < 0.05). Single-cell RNA sequencing data highlighted varying CEA expressions across different cell populations in colorectal cancer. The findings indicated that integrating clinical assessments with accurate biomarkers may provide valuable insights into prognostic implications.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais , Humanos , Prognóstico , Biomarcadores Tumorais/genética , Antígeno Carcinoembrionário , Fator A de Crescimento do Endotélio Vascular , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Microambiente Tumoral
16.
Pak J Med Sci ; 40(4): 589-594, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38544993

RESUMO

Objective: To compare the clinical outcomes of InterTAN nail and proximal femoral nail antirotation (PFNA) internal fixation for the treatment of intertrochanteric fractures in the elderly. Methods: We retrospectively reviewed the clinical records of 151 elderly patients with intertrochanteric fractures treated in The Second People's Hospital of Hefei from October 2019 to December 2021. Among them, 73 patients had undergone InterTAN (InterTAN group) and 78 patients had undergone PFNA (PFNA group) internal fixation. Operation-related variables (operation time, incision length, intraoperative bleeding volume, hospital stays length, and fracture healing time), complications, and Harris scores were compared between the two groups. Results: The operation time and incision length were shorter and the intraoperative bleeding was less in the PFNA group than in the InterTAN group (all P-values <0.05), but the fracture healing time was longer in the PFNA group (P<0.05). We found similar hospital stays and surgical complications in the two groups (P>0.05). In addition, the Harris hip joint scores were significantly higher in the InterTAN group than in the PFNA group at one, six, and twelve months after the operation (P<0.05). Conclusions: InterTAN and PFNA internal fixation have their own advantages in treating patients with intertrochanteric fractures. InterTAN has better postoperative recovery results, while PFNA has less perioperative trauma. Clinically, InterTAN or PFNA should be selected based on the specific conditions of each patient to maximize the therapeutic benefit of each treatment method.

17.
Small ; 19(36): e2302372, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37118858

RESUMO

Atomically precise metal nanoclusters (NCs) represent an emerging sector of light-harvesting antennas by virtue of peculiar atomic stacking fashion, quantum confinement effect, and molecular-like discrete energy band structure. Nevertheless, precise control of charge carriers over metal NCs has yet to be achieved by the short carrier lifetime and intrinsic instability of metal NCs, which renders the complexity of metal NCs-based photosystems with photoredox mechanisms remaining elusive. Herein, fine tuning of charge migration over metal NCs is demonstrated by constructing directional charge transfer channels in multilayered heterostructure enabled by a facile layer-by-layer (LbL) assembly approach, wherein oppositely charged branched poly-ethylenimine (BPEI) and glutathione (GSH)-capped gold NCs [Aux NCs, Au25 (GSH)18 NCs] are alternately deposited on the metal oxide (MOs: TiO2 , WO3 , Fe2 O3 ) substrates. TheAux (Au25 ) NCs layer serves as light-harvesting antennas for engendering charge carriers, andBPEI interim layer uniformly intercalated at the interface of Aux NCs layer constitutes the tandem hole transport channel for motivating the charge transfer cascade, resulting in the considerably enhanced photoelectrochemical water oxidation performances. Besides, poor photo-stability of Aux NCs is surmounted by stimulating the hole transfer kinetics process.

18.
Small ; 19(35): e2300804, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37183292

RESUMO

The rational design of the directional charge transfer channel represents an important strategy to finely tune the charge migration and separation in photocatalytic CO2 -to-fuel conversion. Despite the progress made in crafting high-performance photocatalysts, developing elegant photosystems with precisely modulated interfacial charge transfer feature remains a grand challenge. Here, a facile one-pot method is developed to achieve in situ self-assembly of Pd nanocrystals (NYs) on the transition metal chalcogenide (TMC) substrate with the aid of a non-conjugated insulating polymer, i.e., branched polyethylenimine (bPEI), for photoreduction of CO2 to syngas (CO/H2 ). The generic reducing capability of the abundant amine groups grafted on the molecular backbone of bPEI fosters the homogeneous growth of Pd NYs on the TMC framework. Intriguingly, the self-assembled TMCs@bPEI@Pd heterostructure with bi-directional spatial charge transport pathways exhibit significantly boosted photoactivity toward CO2 -to-syngas conversion under visible light irradiation, wherein bPEI serves as an efficient hole transfer mediator, and simultaneously Pd NYs act as an electron-withdrawing modulator for accelerating spatially vectorial charge separation. Furthermore, in-depth understanding of the in situ formed intermediates during the CO2 photoreduction process are exquisitely probed. This work provides a quintessential paradigm for in situ construction of multi-component heterojunction photosystem for solar-to-fuel energy conversion.

19.
Inorg Chem ; 62(15): 6138-6146, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37000131

RESUMO

Atomically precise metal nanoclusters (NCs) have emerged as feasible alternatives to traditional photosensitizers in solar energy conversion due to the unique atomic stacking mode, quantum size effect, and abundant active sites. Despite the sporadic advancement in fabricating metal NC-based photosystems, most of which are predominantly centered on Au NCs, unleashing atomically precise silver nanoclusters as light-harvesting antennas has still been in the infant stage, with the charge transfer mechanism remaining elusive. Herein, we comprehensively demonstrate the photosensitization effect of Ag NCs in the photoelectrochemical (PEC) water-splitting reaction and strictly evaluate the correlation of photosensitization efficiency with atomic architecture. To these ends, tailor-made negatively charged l-glutathione (GSH)-capped Ag NCs [Agx, Ag9(GSH)6, Ag16(GSH)9, Ag31(GSH)19] as building blocks are controllably deposited on the metal oxide (MOs = TiO2, WO3, Fe2O3) substrate by a facile self-assembly strategy. Benefiting from the highly efficient photosensitization effect of atomically precise Ag NCs, these self-assembled MOs/Ag NC heterostructured photoanodes with an elegant charge transfer interface demonstrate significantly enhanced photoelectrochemical water oxidation performances under visible-light irradiation on account of efficient charge transport from Ag NCs to the MO substrate, substantially prolonging the charge lifetime of Ag NCs. Our work would significantly inspire ongoing interest in unlocking the generic photosensitization capability of atomically precise metal NCs for solar energy conversion.

20.
Inorg Chem ; 62(42): 17454-17463, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827854

RESUMO

Transition-metal chalcogenide quantum dots (TMCs QDs) exhibit emerging potential in the field of solar energy conversion due to large absorption coefficients for light harvesting, quantum size effect, and abundant active sites. However, fine-tuning the photoinduced charge carrier over TMCs QDs to manipulate the directional charge-transfer pathway remains challenging, considering their ultrashort charge lifetime and slow charge-transfer kinetics. To this end, herein, MoSx/PDDA/TMCs QDs heterostructures were exquisitely designed by a simple and green electrostatic self-assembly strategy under ambient conditions, wherein tailor-made negatively charged TMCs QDs stabilized by mercaptoacetic acid (MAA) were precisely self-assembled on the positively charged polydiallyl dimethylammonium chloride (PDDA)-modified MoSx nanoflowers (NFs), forming a well-defined three-dimensional heterostructured nanoarchitecture. As an electron trapping agent, an MoSx NFs cocatalyst benefits the unidirectional electron transfer from TMCs QDs to the ideal active centers on the MoSx NFs surface by tunneling the ultrathin insulating polymer interim layer, thereby boosting the charge separation efficiency and endowing self-assembled MoSx/PDDA/TMCs QDs heterostructures with considerably increased photocatalytic hydrogen evolution activity (1.96 mmol·g-1·h-1) and admirable stability under visible light irradiation. Our work will provide new insights into smart regulation of directional charge transfer over TMCs QDs-based photosystems for solar energy conversion.

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