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1.
Angew Chem Int Ed Engl ; : e202405396, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818672

RESUMO

Reactive oxygen species (ROS) play a crucial role in determining photocatalytic reaction pathways, intermediate species, and product selectivity. However, research on ROS regulation in polymer photocatalysts is still in its early stages. Herein, we successfully achieved series of modulations to the skeleton of Pyrene-alkyne-based (Tetraethynylpyrene (TEPY)) conjugated porous polymers (CPPs) by altering the linkers (1,4-dibromobenzene (BE), 4,4'-dibromobiphenyl (IP), and 3,3'-dibromobiphenyl (BP)). Experiments combined with theoretical calculations indicate that BE-TEPY exhibits a planar structure with minimal exciton binding energy, which favors exciton dissociation followed by charge transfer with adsorbed O2 to produce ⋅O2 -. Thus BE-TEPY shows optimal photocatalytic activity for phenylboronic acid oxidation and [3+2] cycloaddition. Conversely, the skeleton of BP-TEPY is significantly distorted. Its planar conjugation decreases, intersystem crossing (ISC) efficiency increases, which makes it more prone for resonance energy transfer to generate 1O2. Therefore, BP-TEPY displays best photocatalytic activity in [4+2] cycloaddition and thioanisole oxidation. Both above reactant conversion and its product selectivity exceed 99 %. This work systematically reveals the intrinsic structure-activity relationship among the skeleton structure of CPPs, excitonic behavior, and selective generation of ROS, providing new insights for the rational design of highly efficient and selective CPPs photocatalysts.

2.
Angew Chem Int Ed Engl ; 62(45): e202312020, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37728941

RESUMO

Single-ion conductive electrolytes can largely eliminate electrode polarization, reduce the proportion of anion migration and inhibit side reactions in batteries. However, they usually suffer from insufficient ion conductivity due to the strong interaction between cations and cationic receptors. Here we report an ultrafast light-responsive covalent organic frameworks (COF) with sulfonic acid groups modification as the acrylamide polymerization initiator. Benefiting from the reduced electrostatic interaction between Zn2+ and sulfonic acid groups through solvation effects, the as-prepared COF-based hydrogel electrolyte (TCOF-S-Gel) receives an ion conductivity of up to 27.2 mS/cm and Zn2+ transference number of up to 0.89. In addition, sufficient hydrogen bonds endow the single-ion conductive TCOF-S-Gel electrolyte to have good water retention and superb mechanical properties. The assembled Zn||TCOF-S-Gel||MnO2 full zinc-ion battery exhibits high discharge capacity (248 mAh/g at 1C), excellent rate capability (90 mAh/g at 10C) and superior cycling performance. These enviable results enlist the instantaneously photocured TCOF-S-Gel electrolyte to be qualified to large-scaled flexible high-performance quasi-solid-state zinc-ion batteries.

3.
Angew Chem Int Ed Engl ; 62(30): e202305843, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37232089

RESUMO

The development of a new electrolytic water hydrogen production coupling system is the key to realize efficient and low-cost hydrogen production and promote its practical application. Herein, a green and efficient electrocatalytic biomass to formic acid (FA) coupled hydrogen production system has been developed. In such a system, carbohydrates such as glucose are oxidized to FA using polyoxometalates (POMs) as the redox anolyte, while H2 is evolved continuously at the cathode. Among them, the yield of glucose to FA is as high as 62.5 %, and FA is the only liquid product. Furthermore, the system requires only 1.22 V to drive a current density of 50 mA cm-2 , and the Faraday efficiency of hydrogen production is close to 100 %. Its electrical consumption is only 2.9 kWh Nm-3 (H2 ), which is only 69 % of that of traditional electrolytic water. This work opens up a promising direction for low-cost hydrogen production coupled with efficient biomass conversion.

4.
Angew Chem Int Ed Engl ; 61(29): e202202914, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35543927

RESUMO

Active species regulation is a key scientific issue that essentially determines the selectivity and activity of a photocatalyst. Herein, CuI -bridged tetrakis(4-ethynylphenyl)ethene aggregates (T4 EPE-Cu) with photo-regulated 1 O2 and O2 .- generation were demonstrated for selective photocatalytic aerobic oxidation. In this system, transient photovoltage combined with the density functional theory calculations confirmed that Cu-alkynyl was the main oxygen activation site. The adsorbed O2 tends to produce O2 .- because of the potential well effect of Cu-alkynyl under high-energy light excitation. But under low-energy light, O2 tends to produce 1 O2 via resonance energy transfer with Cu-alkynyl. For α-terpinene oxidation, the ratios of 1 O2 products to O2 .- products can be controlled from 1.3 (380 nm) to 10.7 (600 nm). Furthermore, T4 EPE-Cu exhibited ultrahigh photocatalytic performance for Glaser coupling and benzylamine oxidation, with a conversion and selectivity of over 99 %.

5.
J Clin Gastroenterol ; 55(7): 615-623, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33606427

RESUMO

INTRODUCTION AND AIM: Hepatocellular carcinoma (HCC) is a deadly complication among patients with chronic liver disease (CLD). Controversies on the efficacy and safety of statin to prevent HCC among patients with CLD remain despite the growing evidences. We aim to investigate the efficacy and safety of using statin for HCC prevention among adult with CLD. METHODS: We performed a systematic search of 4 electronic databases (PubMed/MEDLINE, EMBASE, Cochrane library, and ClinicalTrial.gov) up to April 15, 2020. We selected all types of studies evaluating the statin use and the risk of HCC among CLD patients, regardless of language, region, publication date, or status. The primary endpoint was the pooled risk of HCC. The secondary endpoint was the risk of statin-associated myopathy. RESULT: From 583 citations, we included a total of 13 studies (1,742,260 subjects, 7 types of statins), fulfilling the inclusion criteria, evaluating efficacy and safety of statin in CLD patients for HCC prevention. All studies were observational (2 nested case-control studies, 11 cohort studies), and no randomised trial was identified. We found that statin user has a lower pooled risk of HCC development (hazard ratio=0.57, 95% confidence interval: 0.52-0.62, I2=42%). HCC reduction was consistent among statin users in cirrhosis, hepatitis B virus, and hepatitis C virus infections. The risk of statin-associated myopathy was similar between statin user and nonuser (hazard ratio=1.07, 95% confidence interval=0.91-1.27). CONCLUSION: Statin use was safe and associated with a lower pooled risk of HCC development among adults with CLD. Given the bias with observation studies, prospective randomised trial is needed to confirm this finding.


Assuntos
Carcinoma Hepatocelular , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Hepáticas , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/prevenção & controle , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Cirrose Hepática , Neoplasias Hepáticas/prevenção & controle , Estudos Prospectivos
6.
Magn Reson Chem ; 59(3): 324-345, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32797694

RESUMO

Nuclear magnetic resonance (NMR) spectroscopy is an important analytical tool in chemistry, biology, and life science, but it suffers from relatively low sensitivity and long acquisition time. Thus, improving the apparent signal-to-noise ratio and accelerating data acquisition became indispensable. In this review, we summarize the recent progress on low-rank Hankel matrix and tensor methods, which exploit the exponential property of free-induction decay signals, to enable effective denoising and spectra reconstruction. We also outline future developments that are likely to make NMR spectroscopy a far more powerful technique.

7.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202302

RESUMO

Magnetic resonance spectroscopy (MRS), as a noninvasive method for molecular structure determination and metabolite detection, has grown into a significant tool in clinical applications. However, the relatively low signal-to-noise ratio (SNR) limits its further development. Although the multichannel coil and repeated sampling are commonly used to alleviate this problem, there is still potential room for promotion. One possible improvement way is combining these two acquisition methods so that the complementary of them can be well utilized. In this paper, a novel coil-combination method, average smoothing singular value decomposition, is proposed to further improve the SNR by introducing repeatedly sampled signals into multichannel coil combination. Specifically, the sensitivity matrix of each sampling was pretreated by whitened singular value decomposition (WSVD), then the smoothing was performed along the repeated samplings' dimension. By comparing with three existing popular methods, Brown, WSVD, and generalized least squares, the proposed method showed better performance in one phantom and 20 in vivo spectra.

8.
Angew Chem Int Ed Engl ; 59(26): 10297-10300, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-31490596

RESUMO

Nuclear magnetic resonance (NMR) spectroscopy serves as an indispensable tool in chemistry and biology but often suffers from long experimental times. We present a proof-of-concept of the application of deep learning and neural networks for high-quality, reliable, and very fast NMR spectra reconstruction from limited experimental data. We show that the neural network training can be achieved using solely synthetic NMR signals, which lifts the prohibiting demand for a large volume of realistic training data usually required for a deep learning approach.

9.
Phys Chem Chem Phys ; 21(31): 17163-17169, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31342023

RESUMO

Two-dimensional (2D) heteromaterials with large interface contact and intimate interfacial charge transition have been considered to be an ideal model for constructing highly efficient photocatalysts. However, few studies have reported on these 2D heterojunctions. Herein, we report a series of new 2D heterojunctions comprising polyimide (PI) and perylene-3,4,9,10-tetracarboxylic dianhydride (TD). These heterojunctions, denoted as PI-TDx (where x represents the amount of TD added, i.e., x = 0.13, 0.18, 0.27, 0.54, and 1.08 g), were prepared by the solid thermal copolymerization of melamine (MA), pyromellitic dianhydride (PD), and different amounts of TD. FT-IR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy analyses were used to verify the 2D heterojunction structure. Photocatalytic experiments reveal that PI-TDx exhibit excellent and stable photocatalytic performance for the degradation of the organic dyes rhodamine B (RhB) and methyl violet (MV), as well as for the photoreduction of Cr(vi), under visible-light irradiation. Among the samples, PI-TD0.18 exhibits the best photocatalytic performance. Its activity is about 2.7 times and 7.5 times higher than that of individual PIMP (formed by MA and PD) and PIMT (formed by MA and TD) for RhB degradation, respectively. Notably, PI-TD0.18 retains a certain photocatalytic activity under light irradiation at 600 nm. The photocatalytic-mechanism study demonstrates that PI-TD0.18 has a classic type-II heterojunction. Its 2D heterojunction greatly enhances the visible-light absorption of the composites and effectively suppresses the radiation recombination of photogenerated carriers, thereby improving its charge transfer and separation abilities and providing excellent photocatalytic performance. This work may serve as an important reference for the design and construction of new highly efficient 2D organic conjugated-polymer photocatalysts.


Assuntos
Poluentes Ambientais/química , Perileno/análogos & derivados , Perileno/química , Resinas Sintéticas/química , Catálise , Cromo/química , Corantes/química , Violeta Genciana/química , Luz , Oxirredução , Processos Fotoquímicos , Rodaminas/química , Propriedades de Superfície
10.
Adv Mater ; : e2407705, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38925587

RESUMO

Polyoxometalates (POMs) have been considered one of the most promising anode candidates for lithium-ion batteries (LIBs) in virtue of their high theoretical capacity and reversible multielectron redox properties. However, the poor intrinsic electronic conductivity, low specific surface area, and high solubility in organic electrolytes hinder their widespread applications in LIBs. Herein, a novel hybrid nanomaterial is synthesized by co-assembling POMs and porphyrins (PMo12/CoTPyP) through a facile solvothermal method. The POM clusters are stabilized by porphyrin units through electrostatic interactions, which simultaneously realize the uniform dispersion of POMs and porphyrin units. Benefiting from the generated sub-1 nm channels for fast ion transport and the synergistic effect between evenly distributed PMo12 clusters and high-conductive CoTPyP units, the LIB based on the optimized PMo12/CoTPyP anode exhibits significantly improved Li+ storage capability as well as superior rate and cycling performance. The results of density functional theory simulations further reveal that the co-assembly of PMo12 and CoTPyP can accelerate the mobility of Li+ and electrons, which in turn promotes the enhancement of LIBs performance. This work paves a strategy for synthesizing POMs-based anode materials with simultaneously high dispersibility, redox activity, and stability.

11.
Adv Sci (Weinh) ; : e2402616, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828766

RESUMO

Although possessing well-defined nanostructures and excellent multi-electron redox properties, polyoxometalate clusters have poor intrinsic electrical conductivity and are prone to aggregation due to large surface energy, which makes them difficult to be fully utilized when applying as electrode materials for lithium-ion batteries. In this paper, monodisperse K7MnV13O38 (MnV13) clusters are achieved by rationally utilizing nano-sized high conductive carbon dots (CDs) as stabilizers. Benefiting from the fully exposed redox sites of MnV13 clusters (high utilization rate) and sufficient interfaces with carbon dots (extra interfacial energy storage), the optimized MnV13/10CDs anode delivers a high discharge capacity up to 1348 mAh g-1 at a current density of 0.1 A g-1 and exhibits superb rate/cycling capabilities. Density functional theory (DFT) calculations verify that ionic archway channels are formed between MnV13 and CDs, eliminating the bandgap and greatly improving the electron/ion conductivity of MnV13 and CDs. This paper paves a brand-new way for synthesis of monodisperse clusters and maximization of extra interfacial energy storage.

12.
Nat Commun ; 15(1): 2605, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521797

RESUMO

Nonlinear transport enabled by symmetry breaking in quantum materials has aroused considerable interest in condensed matter physics and interdisciplinary electronics. However, achieving a nonlinear optical response in centrosymmetric Dirac semimetals via defect engineering has remained a challenge. Here, we observe the helicity dependent terahertz emission in Dirac semimetal PtTe2 thin films via the circular photogalvanic effect under normal incidence. This is activated by a controllable out-of-plane Te-vacancy defect gradient, which we unambiguously evidence with electron ptychography. The defect gradient lowers the symmetry, which not only induces the band spin splitting but also generates the giant Berry curvature dipole responsible for the circular photogalvanic effect. We demonstrate that the THz emission can be manipulated by the Te-vacancy defect concentration. Furthermore, the temperature evolution of the THz emission features a minimum in the THz amplitude due to carrier compensation. Our work provides a universal strategy for symmetry breaking in centrosymmetric Dirac materials for efficient nonlinear transport.

13.
Expert Rev Mol Diagn ; 23(11): 959-970, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37750512

RESUMO

INTRODUCTION: Precision medicine based on the driver genes mutation status is the current systemic therapeutic paradigm in patients with lung cancer. Next-generation sequencing (NGS) has emerged as a powerful platform for molecular diagnosis by virtue of high-throughput and massively parallel sequencing. Liquid biopsy also enabled the dynamic monitoring and comprehensive profiling of lung cancer in a noninvasive manner. However, challenges remain in the field of technology and clinical applications, especially in the era of immunotherapy. AREAS COVERED: Here, we update the role of NGS in the context of lung cancer screening, molecular diagnosis, predictive and prognostic biomarkers, and guiding personalized treatment. EXPERT OPINION: The NGS application for actable genomic alternation has greatly changed the therapeutic landscape in patients with lung cancer including perioperative setting and advanced stage. Meanwhile, emerging evidence has shown the potential of other applications such as early screening and detection, and MRD. However, challenges remain such as the lack of standardized protocols across different platforms and bioinformatics analysis pipelines, and the complexity of interpreting and leveraging numerous genomic mutation messages for therapy selection. Future research is needed to overcome these challenges and expand the applications of NGS to other aspects such as immunotherapy.

14.
Chin Med J (Engl) ; 136(4): 379-393, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36848213

RESUMO

ABSTRACT: Monoclonal antibodies have been successfully incorporated into the current therapeutical landscape of lung cancer in the last decades. Recently, with technological advances, bispecific antibodies (bsAbs) have also shown robust efficacy in the treatment of malignant cancers, including lung cancer. These antibodies target two independent epitopes or antigens and have been extensively explored in translational and clinical studies in lung cancer. Here, we outline the mechanisms of action of bsAbs, related clinical data, ongoing clinical trials, and potent novel compounds of various types of bsAbs in clinical studies, especially in lung cancer. We also propose future directions for the clinical development of bsAbs, which might bring a new era of treatment for patients with lung cancer.


Assuntos
Anticorpos Biespecíficos , Neoplasias Pulmonares , Humanos , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico
15.
Chem Commun (Camb) ; 59(36): 5475-5478, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37070867

RESUMO

Nuclear magnetic resonance (NMR) spectroscopy has become a formidable tool for biochemistry and medicine. Although J-coupling carries essential structural information it may also limit the spectral resolution. Homonuclear decoupling remains a challenging problem. In this work, we introduce a new approach that uses a specific coupling value as prior knowledge, and the Hankel property of the exponential NMR signal to achieve broadband heteronuclear decoupling using the low-rank method. Our results on synthetic and realistic HMQC spectra demonstrate that the proposed method not only effectively enhances resolution by decoupling, but also maintains sensitivity and suppresses spectral artefacts. The approach can be combined with non-uniform sampling, which means that the resolution can be further improved without any extra acquisition time.

16.
Nat Nanotechnol ; 18(8): 854-860, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37169899

RESUMO

Hysteretic switching of domain states is a salient characteristic of all ferroic materials and the foundation for their multifunctional applications. Ferro-rotational order is emerging as a type of ferroic order that features structural rotations, but control over state switching remains elusive due to its invariance under both time reversal and spatial inversion. Here we demonstrate electrical switching of ferro-rotational domain states in the charge-density-wave phases of nanometre-thick 1T-TaS2 crystals. Cooling from the high-symmetry phase to the ferro-rotational phase under an external electric field induces domain state switching and domain wall formation, which is realized in a simple two-terminal configuration using a volt-scale bias. Although the electric field does not couple with the order due to symmetry mismatch, it drives domain wall propagation to give rise to reversible, durable and non-volatile isothermal state switching at room temperature. These results offer a route to the manipulation of ferro-rotational order and its nanoelectronic applications.

17.
Adv Mater ; 35(19): e2207841, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36905678

RESUMO

2D transition metal dichalcogenides are promising platforms for next-generation electronics and spintronics. The layered Weyl semimetal (W,Mo)Te2 series features structural phase transition, nonsaturated magnetoresistance, superconductivity, and exotic topological physics. However, the superconducting critical temperature of the bulk (W,Mo)Te2 remains ultralow without applying a high pressure. Here, the significantly enhanced superconductivity is observed with a transition temperature as large as about 7.5 K in bulk Mo1- x Tax Te2 single crystals upon Ta doping (0 ≤ x ≤ 0.22), which is attributed to an enrichment of density of states at the Fermi level. In addition, an enhanced perpendicular upper critical field of 14.5 T exceeding the Pauli limit is also observed in Td -phase Mo1- x Tax Te2 (x = 0.08), indicating the possible emergence of unconventional mixed singlet-triplet superconductivity owing to the inversion symmetry breaking. This work provides a new pathway for exploring the exotic superconductivity and topological physics in transition metal dichalcogenides.

18.
Lung Cancer ; 181: 107233, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37201296

RESUMO

BACKGROUND: Programmed cell death-ligand 1 (PD-L1) expression was found to be a biomarker of inferior efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in EGFR-mutated non-small cell lung cancer (NSCLC). However, whether PD-L1 expression could also serve as a similar biomarker in anaplastic lymphoma kinase (ALK)-positive patients, especially for those treated with front-line alectinib, remains unclear. The aim of the study is to investigate the association of PD-L1 expression and efficacy of alectinib in this setting. METHODS: From January 2018 to March 2020, 225 patients with ALK-rearranged lung cancer were consecutively collected at Shanghai Pulmonary Hospital, Tongji University. Baseline PD-L1 expression was detected using immunohistochemistry (IHC) in 56 patients of advanced ALK-rearranged lung cancer who received front-line alectinib. RESULTS: Among the 56 eligible patients, 30 (53.6%) were PD-L1 expression negative, 19 (33.9%) patients had TPS 1%-49% and 7 (12.5%) had TPS ≥ 50%.We found no statistically significant associations between PD-L1 positivity and objective response rate (ORR, 90.0% vs. 80.8%, p = 0.274) or progression-free survival (PFS, not reached vs. not reached, HR: 0.98, 95 %CI: 0.37-2.61, p = 0.97) in patients treated with alectinib. Meanwhile, patients with PD-L1 high expression (TPS ≥ 50%) had a trend of longer PFS (not reached vs. not reached, p = 0.61). CONCLUSIONS: PD-L1 expression might not serve as a predict biomarker for the efficacy of front-line alectinib in ALK-positive NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Antígeno B7-H1/metabolismo , Quinase do Linfoma Anaplásico , China , Receptores ErbB , Inibidores de Proteínas Quinases
19.
Eur Heart J Case Rep ; 5(1): ytaa429, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33644640

RESUMO

BACKGROUND: Painless aortic dissection presenting with seizure and acute liver failure is uncommon. We described a case of early recognition leading to successful treatment of painless aortic dissection with atypical presentation. CASE SUMMARY: A young lady presented with generalized tonic-clonic seizures coupled with hepatitic pattern of deranged liver function test. Examination revealed blood pressure of 99/75 mmHg and hepatic flap. Electrocardiography showed sinus tachycardia. Urgent bedside echocardiography showed preserved cardiac function without significant valvular pathology, but noted a moderate pericardial effusion. Abdominal Ultrasound excluded liver cirrhosis or biliary obstructions. Viral hepatitis serologies and anti-liver panel were negative. She was progressively hypotensive with concurrent acute liver failure and oliguric acute kidney injury. Despite no chest pain, her rising serum troponin and widened mediastinum prompted an urgent computed-tomography aortogram, which showed a 4.3 cm dilatation of ascending thoracic aorta with acute haemopericardium and cardiac tamponade. She was diagnosed with malperfusion syndrome from Stanford type A aortic dissection. She underwent emergent ascending aorta and aortic arch repair and dialysis. She experienced complete recovery in her kidney, liver, and neurological function post-operatively. DISCUSSION: Painless aortic dissection masquerade as acute liver failure is uncommon. We describe a successful early recognition of malperfusion syndrome from painless aortic dissection, thus providing window for timely, life-saving intervention. Clinical challenges in this case include: (i) atypical presentation of aortic dissection, (ii) worsening acute liver failure which could lead to unnecessary liver transplantation, and (iii) risk of contrast-induced nephropathy in the setting of acute renal failure.

20.
ACS Appl Mater Interfaces ; 13(20): 23866-23876, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33998224

RESUMO

Constructing bulk defects and doping are feasible ways to essentially narrow the band gap and improve the light absorption of photocatalysts. Herein, inspired by bread foaming, the foaming agent azoformamide or azodicarbonamide (AC) was introduced during the thermal polymerization of urea. In the polymerization process, a large number of bubbles produced by AC decomposition seriously interfered with the polymerization of urea, resulting in the breaking of the hydrogen bonds and van der Waals interaction in carbon nitride, distortion of its structure, and partial oxidation, thus forming a series of porous carbon nitrides U/ACx (x is the ratio of AC to urea; where x = 0.25, 0.5, and 1) with bulk N defects and O doping. Its band gap was reduced to 1.91 eV and the absorption band edge was greatly extended to 650 nm. The optimal U/AC0.5 exhibits the highest visible light photocatalytic hydrogen production rate of about 44.7 µmol·h-1 (10 mg catalysts) and shows superior photocatalytic performance for the oxidation of diphenylhydrazine to azobenzene, with conversion and selectivity of almost 100%, and is one of the most active defective carbon nitrides, especially under long-wavelength (λ ≥ 550 nm) light irradiation. It paves the way for the design of highly efficient and wide-spectral-response photocatalysts.

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