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Photoenzyme-coupled catalytic systems offer a promising avenue for selectively converting CO2 into high-value chemicals or fuels. However, two key challenges currently hinder their widespread application: the heavy reliance on the costly coenzyme NADH, and the necessity for metal-electron mediators or photosensitizers to address sluggish reaction kinetics. Herein, we present a robust 2D/2D MXene/C3N5 heterostructured artificial photosynthesis platform for in situ NADH regeneration and photoenzyme synergistic CO2 conversion to HCOOH. The efficiencies of utilizing and transmitting photogenerated charges are significantly enhanced by the abundant π-π conjugation electrons and well-engineered 2D/2D hetero-interfaces. Noteworthy is the achievement of nearly 100 % NADH regeneration efficiency within just 2.5 h by 5 % Ti3C2/C3N5 without electron mediators, and an impressive HCOOH production rate of 3.51 mmol g-1h-1 with nearly 100 % selectivity. This study represents a significant advancement in attaining the highest NADH yield without electron mediator and provides valuable insights into the development of superior 2D/2D heterojunctions for CO2 conversion.
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Sonodynamic therapy (SDT) relies heavily on the presence of oxygen to induce cell death. Its effectiveness is thus diminished in the hypoxic regions of tumor tissue. To address this issue, the exploration of ultrasound-based synergistic treatment modalities has become a significant research focus. Here, we report an ultrasonic cavitation effect enhanced sonodynamic and 1208 nm photo-induced cancer treatment strategy based on thermoelectric/piezoelectric oxygen-defect bismuth oxychloride nanosheets (BNs) to realize the high-performance eradication of tumors. Upon ultrasonic irradiation, the local high temperature and high pressure generated by the ultrasonic cavitation effect combined with the thermoelectric and piezoelectric effects of BNs create a built-in electric field. This facilitates the separation of carriers, increasing their mobility and extending their lifetimes, thereby greatly improving the effectiveness of SDT and NIR-â ¡ phototherapy on hypoxia. The Tween-20 modified BNs (TBNs) demonstrate â¼88.6 % elimination rate against deep-seated tumor cells under hypoxic conditions. In vivo experiments confirm the excellent antitumor efficacy of TBNs, achieving complete tumor elimination within 10 days with no recurrences. Furthermore, due to the high X-ray attenuation of Bi and excellent NIR-â ¡ absorption, TBNs enable precise cancer diagnosis through photoacoustic (PA) imaging and computed tomography (CT).
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Bismuto , Neoplasias da Mama , Oxigênio , Terapia por Ultrassom , Bismuto/química , Feminino , Animais , Neoplasias da Mama/terapia , Terapia por Ultrassom/métodos , Oxigênio/química , Camundongos , Camundongos Endogâmicos BALB C , Humanos , Linhagem Celular Tumoral , Raios Infravermelhos , Nanoestruturas/química , Fototerapia/métodosRESUMO
Crafting semiconducting heterojunctions represents an effective route to enhance photocatalysis by improving interfacial charge separation and transport. However, lattice mismatch (δ) between different semiconductors can significantly hinder charge dynamics. Here, meticulous lattice tailoring is reported to create a covalent heterointerface with a built-in electric field (BIEF), imparting markedly improved hydrogen peroxide (H2O2) photosynthesis. Specifically, an In2S3/CdS heterojunction with a coherent heterointerface, characterized by covalent InâSâCd bridge and exceptionally low lattice mismatch of 0.27%, and a BIEF from In2S3 to CdS, is rationally designed. This heterojunction entails rapid charge separation and transfer, achieving an outstanding H2O2 production rate of 2.09 mmol g-1 h-1 without the need for scavengers and oxygen bubbling, and a high apparent quantum efficiency of 17.73% at 400 nm. Density functional theory (DFT) calculations further reveal that this Z-scheme heterojunction facilitates the adsorption of *O2 and the generation of *OOH intermediates during the 2e- oxygen reduction reaction, associated with a low Gibbs free energy. This study underscores the significance of fine-tuning interfacial lattices and integrating BIEF to accelerate photocatalysis. The simple yet robust strategy can be conveniently leveraged to enhance device performance in optoelectronics, electrocatalysis, photoelectrocatalysis, and sensing.
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As donors for effective energy transfer, metal-organic frameworks (MOFs) have attracted the attention of many experts in the field of artificial light-harvesting materials. This study introduces a novel two-dimensional Zn-MOF, synthesized using flexible 1,3-phenyldiacetic acid (H2mpda) and rigid 1,3,5-tris(1-imidazolyl)benzene (tib) as organic ligands. Through atomic force microscopy (AFM), we have determined the monolayer thickness of this novel material to be 5 nm. Achieving two-dimensional Zn-MOF nanosheets with large BET surface area was made possible by employing ultrasonic stripping techniques. The fluorescence emission spectrum of Zn-MOF nanosheets overlaps with the UV-vis absorption spectrum of coumarin 6 (CM6), so they can be used as a donor and acceptor for fluorescence resonance energy transfer (FRET) to construct an artificial light-harvesting system (ALHS). Compared with single crystal Zn-MOF, CM6@Zn-MOF(2) has a larger BET surface area (41 m2/g), higher quantum yield (Φfl, 30.56 %), narrower energy gap (Eg, 2.87 eV), and the light-harvesting range extends to the visible green light area. Notably, CM6@Zn-MOF(2) demonstrates a robust photocurrent response, characterized by a photocurrent on/off ratio (Ilight/Idark) of 21, and a maximum photocurrent density that surpasses that of pure Zn-MOF (2.25:1). This study successfully designed a high-performance photoelectric conversion material CM6@Zn-MOF(2), which laid a certain theoretical foundation for new artificial optical acquisition systems and electrochemical material selection.
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The incorporation of difluoroboron ß-diketonate and tetraphenylethene under a facile Knoevenagel condensation reaction afforded one new D-π-A-π-D complex TCBF with high aggregation-induced emission (AIE) activity. The TCBF film can maintain a high photocurrent after long-term (500 min) photoelectronic measurements. The successful fabrication of a red LED device makes it a promising candidate for high-performance solid-state lighting.
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Phosphor-converted white light-emitting diodes (PC-WLEDs) have attracted considerable attention in solid-state lighting and display. However, urgent issues of thermal quenching and high cost remain formidable challenges. Herein, a novel metal-organic framework (MOF) phosphor [CdCl2(AD)] was facilely prepared using a mixture of CdCl2 and acridine (AD) under solvothermal conditions. It shows intensive green emission with a long lifetime of 31.88 ns and quantum yield of 65% while maintaining 95% and 84% of its initial emission intensity after remaining immersed in water for 60 days and being heated to 150 °C, respectively. The low thermal quenching of this MOF material is comparable to or can even exceed that of commercial inorganic phosphors. The combination of experiments and theoretical calculations reveals that the alternating arrangement of delocalized AD π-conjugated systems and CdCl2 inorganic chains through strong coordination bonds and πâ¯π stacking interactions imparts the MOF phosphor with high thermal stability and optoelectronic performance. The successful fabrication of green and white LED devices by coating [CdCl2(AD)] and/or N630 red phosphor on a 365/460 nm commercial diode chip suggests a promising and potential alternative to commercial phosphors.
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BACKGROUND: A proportion of Haematococcus pluvialis under the light stress can effectively conduct astaxanthin biosynthesis, leading to the increase in cell size. Although the size is a critical indicator for identifying the astaxanthin-rich H. pluvialis cells, the cut-off size to be separated varies from sample to sample. RESULTS: Here, we report an ultrastretchable, straight elasto-inertial microchannel with tunable separation threshold to continuously separate the light-induced H. pluvialis cells by size. The symmetrical sheath flows confine the particles to the channel sidewalls, and large particles can cross the interface of viscoelastic fluids to the equilibrium position at the channel centerline. By stretching the microfluidic chip, the medium-sized particles can gradually migrate to the channel centerline in the narrower and longer channel, bringing the tunable separation threshold. Results show that the separation performance of the ultrastretchable microfluidic device is affected by total flow rate, flow rate ratio of sheath to sample, polyethylene oxide (PEO) solution configuration. Lastly, size-tunable separation of light-induced H. pluvialis cells is demonstrated. SIGNIFICANCE: To the best of our knowledge, this is the first report on cell migration in co-flow configurations in the ultra-stretchable microfluidics. Separation of H. pluvialis is not only a relevant end application in harvesting the astaxanthin-rich species, but the separated populations of highly productive microalgal cells will open a venue for cellular directed evolution.
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Dispositivos Lab-On-A-Chip , Luz , Clorofíceas/química , Xantofilas/química , Xantofilas/isolamento & purificação , Técnicas Analíticas Microfluídicas/instrumentação , Tamanho da PartículaRESUMO
Since 2020, covalent organic frameworks (COFs) are emerging as robust catalysts for the photosynthesis of hydrogen peroxide (H2O2), benefiting from their distinct advantages. However, the current efficiency of H2O2 production and solar-to-chemical energy conversion efficiency (SCC) remain suboptimal due to various constraints in the reaction mechanism. Therefore, there is an imperative to propose efficiency improvement strategies to accelerate the development of this reaction system. This comprehensive review delineates recent advances, challenges, and strategies in utilizing COFs for photocatalytic H2O2 production. It explores the fundamentals and challenges (e.g., oxygen (O2) mass transfer rate, O2 adsorption capacity, response to sunlight, electron-hole separation efficiency, charge transfer efficiency, selectivity, and H2O2 desorption) associated with this process, as well as the advantages, applications, classification, and preparation strategies of COFs for this purpose. Various strategies to enhance the performance of COFs in H2O2 production are highlighted. The review aims to stimulate further advancements in utilizing COFs for photocatalytic H2O2 production and discusses potential prospects, challenges, and application areas in this field.
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The alteration of intermediates on the (010) facet of BiVO4 leads to variations in charge accumulation numbers before overcoming the rate-determining step, which accounts for the enhanced charge transfer for oxygen evolution. This discovery provides insights into the photocharging effect and the photoelectrochemical reaction mechanism.
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Background: In addition to the well-known Whipple's disease (WD), Tropheryma Whipplei (TW) can also lead to acute pneumonia. There is no unified consensus on the susceptible population, pathogenesis, clinical manifestations, diagnostic criteria, and treatment options for TW pneumonia. Clinical Presentation and Intervention: This is an elderly patient with multiple injuries caused by falling from a building, and was transferred to intensive care unit (ICU) for mechanical ventilation and empirical anti-infection treatment due to severe pneumonia, and then the results of targeted next-generation sequencing (tNGS) in patient's bronchoalveolar lavage fluid (BALF) suggested TW and human metapneumovirus (HMPV) infection, and after switching to anti-infective therapy for TW, the patient was successfully extubated and transferred out of the ICU. Conclusion: This is the first case of using tNGS to diagnose severe pneumonia caused by TW and HMPV. We hope that our study can serve as a reference for the diagnosis and treatment of related cases in the future.
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Objective: Glioblastoma is the most common and aggressive type of the central nervous system cancers. Although radiotherapy and chemotherapy are used in the treatment of glioblastoma, survival rates remain unsatisfactory. This study aimed to explore differentially expressed genes (DEGs) based on the survival prognosis of patients with glioblastoma and to establish a model for classifying patients into different risk groups for overall survival. Methods: DEGs from 160 tumor samples from patients with glioblastoma and 5 nontumor samples from other patients in The Cancer Genome Atlas database were identified. Functional enrichment analysis and a protein-protein interaction network were used to analyze the DEGs. The prognostic DEGs were identified by univariate Cox regression analysis. We split patient data from The Cancer Genome Atlas database into a high-risk group and a low-risk group as the training data set. Least absolute shrinkage and selection operator and multiple Cox regression were used to construct a prognostic risk model, which was validated in a test data set from The Cancer Genome Atlas database and was analyzed using external data sets from the Chinese Glioma Genome Atlas database and the GSE74187 and GSE83300 data sets. Furthermore, we constructed and validated a nomogram to predict survival of patients with glioblastoma. Results: A total of 3572 prognostic DEGs were identified. Functional analysis indicated that these DEGs were mainly involved in the cell cycle and focal adhesion. Least absolute shrinkage and selection operator regression identified 3 prognostic DEGs (EFEMP2, PTPRN, and POM121L9P), and we constructed a prognostic risk model. The receiver operating characteristic curve analysis showed that the areas under the curve were 0.83 for the training data set and 0.756 for the test data set. The predictive performance of the prognostic risk model was validated in the 3 external data sets. The nomogram showed that the prognostic risk model was reliable and that the accuracy of predicting survival in each patient was high. Conclusion: The prognostic risk model can effectively classify patients with glioblastoma into high-risk and low-risk groups in terms of overall survival rate, which may help select high-risk patients with glioblastoma for more intensive treatment.
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Marine heatwaves (MHWs) have a significant impact on intertidal bivalves and the ecosystems they sustain, causing the destruction of organisms' original habitats. Saccostrea mordax mainly inhabits the intertidal zone around the equator, exhibiting potential tolerance to high temperatures and maybe a species suitable for habitat restoration. However, an understanding about the tolerance mechanism of S. mordax to high temperatures is unclear. It is also unknown the extent to which S. mordax can tolerate repeated heatwaves of increasing intensity and frequency. Here, we simulated the effects of two scenarios of MHWs and measured the physiological and biochemical responses and gene expression spectrum of S. mordax. The predicted responses varied greatly across heatwaves, and no heatwave had a significant impact on the survival of S. mordax. Specifically, there were no statistically significant changes apparent in the standard metabolic rate and the activities of enzymes of the oyster during repeated heatwaves. S. mordax exposed to high-intensity heatwaves enhanced their standard metabolic rate to fuel essential physiological maintenance and increasing activity of SOD and expression of HSP70/90. These strategies are presumably at the expense of functions related to immunity and growth, as best exemplified by significant depressions in activities of enzymes (NaK, CaMg, T-ATP, and AKP) and expression levels of genes (Rab, eEF-2, HMGR, Rac1, SGK, Rab8, etc.). The performance status of S. mordax tends to improve by implementing a suite of less energy-costly compensatory mechanisms at various levels of biological organization when re-exposed to heatwaves. The adaptive abilities shown by S. mordax indicate that they can play a crucial role in the restoration of oyster reefs in tropical seas.
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Ostreidae , Animais , Ostreidae/fisiologia , Recifes de Corais , Calor Extremo , Ecossistema , Temperatura Alta , TermotolerânciaRESUMO
Solar-driven carbon dioxide (CO2) methanation holds significant research value in the context of carbon emission reduction and energy crisis. However, this eight-electron catalytic reaction presents substantial challenges in catalytic activity and selectivity. In this regard, researchers have conducted extensive exploration and achieved significant developments. This review provides an overview of the recent advances and challenges in efficient selective photocatalytic CO2 methanation. It begins by discussing the fundamental principles and challenges in detail, analyzing strategies for improving the efficiency of photocatalytic CO2 conversion to CH4 comprehensively. Subsequently, it outlines the recent applications and advanced characterization methods for photocatalytic CO2 methanation. Finally, this review highlights the prospects and opportunities in this area, aiming to inspire CO2 conversion into high-value CH4 and shed light on the research of catalytic mechanisms.
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Artificial photosynthesis for hydrogen peroxide (H2O2) presents a sustainable and environmentally friendly approach to generate clean fuel and chemicals. However, the catalytic activity is hindered by challenges such as severe charge recombination, insufficient active sites, and poor selectivity. Here, a robust strategy is proposed to regulate the electronic structure of catalyst by the collaborative effect of defect engineering and dopant. The well designed oxygen-doped CdS nanorods with S2- defects and Cd2+ 4d10 electron configuration (CdS-O,Sv) is successfully synthesized, and the Cd2+ active sites around S defects or oxygen atoms exhibit rapid charge separation, suppressed carrier recombination, and enhanced charge utilization. Consequently, a remarkable H2O2 production rate of 1.62 mmol g-1 h-1 under air conditions is acquired, with an apparent quantum yield (AQY) of 9.96% at a single wavelength of 450 nm. This work provides valuable insights into the synergistic effect between defect and doping on catalytic activity.
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The most challenging obstacle for photocatalysts to efficiently harvest solar energy is the sluggish surface redox reaction (e. g., oxygen evolution reaction, OER) kinetics, which is believed to originate from interface catalysis rather than the semiconductor photophysics. In this work, we developed a light-modulated transient photocurrent (LMTPC) method for investigating surface charge accumulation and reaction on the W-doped bismuth vanadate (W : BiVO4) photoanodes during photoelectrochemical water oxidation. Under illuminating conditions, the steady photocurrent corresponds to the charge transfer rate/kinetics, while the integration of photocurrent (I~t) spikes during the dark period is regarded as the charge density under illumination. Quantitative analysis of the surface hole densities and photocurrents at 0.6â V vs. reversible hydrogen electrode results in an interesting rate-law kinetics switch: a 3rd-order charge reaction behavior appeared on W : BiVO4, but a 2nd-order charge reaction occurred on W : BiVO4 surface modified with ultrathin Bi metal-organic-framework (Bi-MOF). Consequently, the photocurrent for water oxidation on W : BiVO4/Bi-MOF displayed a 50 % increment. The reaction kinetics alternation with new interface reconstruction is proposed for new mechanism understanding and/or high-performance photocatalytic applications.
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Nitrogen cycle is crucial for the Earth's ecosystem and human-nature coexistence. However, excessive fertilizer use and industrial contamination disrupt this balance. Semiconductor-based artificial nitrogen cycle strategies are being actively researched to address this issue. Black phosphorus (BP) exhibits remarkable performance and significant potential in this area due to its unique physical and chemical properties. Nevertheless, its practical application is hindered by ambient instability. This review covers the synthesis methods of BP materials, analyzes their instability factors under environmental conditions, discusses stability improvement strategies, and provides an overview of the applications of ambient-stable BP materials in nitrogen cycle, including N2 fixation, NO3- reduction, NOx removal and nitrides sensing. The review concludes by summarizing the challenges and prospects of BP materials in the nitrogen cycle, offering valuable guidance to researchers.
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Ecossistema , Fósforo , Humanos , Fósforo/química , Ciclo do Nitrogênio , Fenômenos Físicos , CatáliseRESUMO
The development of efficient and low-cost catalysts for cathodic oxygen reduction reaction (ORR) in Zn-air battery (ZAB) is a key factor in reducing costs and achieving industrialization. Here, a novel segregated CoNiPt alloy embedded in N-doped porous carbon with a nanoflowers (NFs)-like hierarchy structure is synthesized through pyrolyzing Hofmann-type metal-organic frameworks (MOFs). The unique hierarchical NFs structure exposes more active sites and facilitates the transportation of reaction intermediates, thus accelerating the reaction kinetics. Impressively, the resulting 15% CoNiPt@C NFs catalyst exhibits outstanding alkaline ORR activity with a half-wave potential of 0.93 V, and its mass activity is 7.5 times higher than that of commercial Pt/C catalyst, surpassing state-of-the-art noble metal-based catalysts. Furthermore, the assembled CoNiPt@C+RuO2 ZAB demonstrates a maximum power density of 172 mW cm-2 , which is superior to that of commercial Pt/C+RuO2 ZAB. Experimental results reveal that the intrinsic ORR mass activity is attributed to the synergistic interaction between oxygen defects and pyrrolic/graphitic N species, which optimizes the adsorption energy of the intermediate species in the ORR process and greatly enhances catalytic activity. This work provides a practical and feasible strategy for synthesizing cost-effective alkaline ORR catalysts by optimizing the electronic structure of MOF-derived catalysts.
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Luminescent coordination polymers (LCPs) have garnered significant attention from researchers as promising materials for detecting contaminants. In this paper, three new LCPs ([Zn(tib)(opda)]nâ H2O (1), [Zn3(tib)2(mpda)3]nâ 5H2O (2), [Zn (tib)(ppda)]nâ H2O (3)) with different structures (LCP 1-3: 1D, 2D, 1D) using phenylenediacetic acid isomers and 1,3,5-tris (1-imidazolyl) benzene (tib) are synthesized. The specific surface areas (BET) of LCP 1-3 are 4 m2/g, 19 m2/g, and 13 m2/g respectively. LCP 1-3 exhibit excellent fluorescence properties and can serve as fluorescent probe for the detection of inorganic contaminants and organic contaminants. Due to the large BET of LCP 2, the detection limits for trace analytes surpass those of LCP 1 and 3. The detection limits of LCP 2 for Fe3+, nitrobenzene (NB), chloramphenicol (CAP), and pyrimethanil (PTH) are 8.3 nM, 0.016 µM, 0.19 µM, and 0.032 µM, respectively, and the fluorescence quenching rates are 98.6 %, 98.8 %, 92.3 %, and 98.8 %, respectively. These values outperform most reported in the literature. The quantum yields of LCP 1-3 are 11.84 %, 25.22 %, 22.00 % respectively. Real sample testing of LCP 1-3 reveals favorable performance, where spiked recoveries of LCP 2 for the detection of pyrimethanil in grape skins ranged from 99.62 % to 119.3 % with a relative standard deviation (RSD) of 0.627 % to 4.56 % (n = 3). The fluorescence quenching mechanism was attributed to a combination of photoelectron transfer (PET), resonance energy transfer (RET), and competitive absorption (CA). This study advances the application of LCPs in luminescence sensing and contributes to the expansion of novel materials for detecting environmental pollutants.
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Single component white-light-emitting (SCWLE) materials are extremely desired in the field of solid-state lighting. However, pure-phosphorescent SCWLE has rarely been reported. Herein, one halogen-bonding-containing MOF [Cd(5-BIPA)(phen)] (1) has been synthesized, which shows efficient white-light emission originating from dual phosphorescence bands with different wavelengths and lifetimes. The fabrication of a phosphor-converted white-light-emitting diode device driven by pulsing current enables this MOF to be a promising phosphor.
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Resorcinol-formaldehyde (RF) resin represents a promising visible-light responding photocatalyst for oxygen reduction reaction (ORR) toward H2 O2 production. However, its photocatalytic ORR activity toward H2 O2 generation is still unsatisfied for practical application. Herein, 3-hydroxythiophenol-formaldehyde (3-HTPF) resin microspheres synthesized through polycondensation reaction between 3-HTP and formaldehyde at room temperature and subsequent hydrothermal treatment exhibit enhanced photocatalytic ORR activity is reported. The experimental results show that the partial substitution of hydroxy group (âOH) by sulfhydryl one (âSH) through using 3-HTP to replace resorcinol could slow the rates of nucleation and growth of the resin particles and lead to strongly π-stacked architecture in 3-HTPF. The introduction of âSH group can also improve adsorption ability of 3-HTPF to O2 molecules and enhance ORR catalytic activity of the photocatalysts. Stronger built-in electric field, better adsorption ability to O2 molecules, and increased surface catalytic activity collectively boost photocatalytic activity of 3-HTPF microspheres. As a result, H2 O2 production rate of 2010 µm h-1 is achieved over 3-HTPF microspheres at 273 K, which is 3.4 times larger than that obtained using RF submicrospheres (591 µm h-1 ). The rational substituent group modulation provides a new strategy for designing polymeric photocatalysts at the molecular level toward high-efficiency artificial photosynthesis.