Electronic Paper Research Articles

Distance-Based Self-Powered Signal Transduction of Ion-Selective Electrodes to an Electronic Paper Display Array.

In this article, we report on the first distance-based readout self-powered potentiometric sensor. The approach is considered more user-friendly for detection by the naked eye and is less prone to optical interferences compared with a direct observation of the pixel darkening. pH-selective electrodes were chosen as a model system to demonstrate the principle in which seven bar-shaped pixels connected in series on one e-paper share one common ground. By connecting each of the pixels serially to capacitors of different capacitances, the fraction of the measurement cell voltage loaded onto the pixels becomes controllable. Consequently, the pixels give different gray values when powered by the same ion-selective electrode (ISE). As a result, the pH information on the sample is visualized as a distance-based signal and the dependence between the capacitance and 1/K (the reciprocal slope in the relationship between absorbance and pH) was constructed. In the current system, a 1 μF capacitance difference changes the value of 1/K by 4.18. With the current setup, the pH accuracy is about 0.5 when comparing the e-paper output to a color card.

The role of photorespiration in preventing feedback regulation via ATP synthase in Nicotiana tabacum.

Photorespiration consumes substantial amounts of energy in the forms of adenosine triphosphate (ATP) and reductant making the pathway an important component in leaf energetics. Because of this high reductant demand, photorespiration is proposed to act as a photoprotective electron sink. However, photorespiration consumes more ATP relative to reductant than the C3 cycle meaning increased flux disproportionally increases ATP demand relative to reductant. Here we explore how energetic consumption from photorespiration impacts the flexibility of the light reactions in nicotiana tabacum. Specifically, we demonstrate that decreased photosynthetic efficiency (ϕII ) at low photorespiratory flux was related to feedback regulation at the chloroplast ATP synthase. Additionally, decreased ϕII at high photorespiratory flux resulted in the accumulation of photoinhibition at photosystem II centers. These results are contrary to the proposed role of photorespiration as a photoprotective electron sink. Instead, our results suggest a novel role of ATP consumption from photorespiration in maintaining ATP synthase activity, with implications for maintaining energy balance and preventing photodamage that will be critical for plant engineering strategies.

Promoting photo-Fenton reactions by anchoring Fe doped g-C3N4 onto an amidoxime-functionalized fibrous support for organic contaminants removal

Fe-doped graphitic carbon nitride (g-C3N4) represents an attractive photo-Fenton catalyst for organic contaminants removal, but the practical performances still need to be improved for large-scale application. Herein, we developed a high-efficiency photo-Fenton catalyst by anchoring Fe-g-C3N4 onto an amidoxime-functionalized polyacrylonitrile fiber (AP) substrate through a simple hydrothermal approach. Comprehensive characterizations demonstrate the strong catalyst-support interaction via the axial coordination bonding between -OH groups and Fe3+, which could induce electric polarization of Fe-g-C3N4 to promote the H2O2 adsorption and activation. The fibrous support could also accelerate the photoelectrons transfer from g-C3N4 to Fe3+ by strengthening the d-π conjugated large π bond, as well as alleviate the backflow recombination from Fe3+ to g-C3N4 through the electron sink effect. These synergistic qualities resulted in superior photo-Fenton performance for organic contaminants removal, which delivered 4.0-fold higher degradation kinetics than that of the Fe doped g-C3N4 powder catalyst and exhibited unexpected high activity at strong basic environment (pH = 12). Our work demonstrates an ingenious and simple way to design exceptional photo-Fenton catalysts for environmental remediation.

Production of poly (3-hydroxybutyrate) and extracellular polymeric substances from glycerol by the acidophile Acidiphilium cryptum.

Acidiphilium cryptum is an acidophilic, heterotrophic, and metallotolerant bacteria able to use dissolved oxygen or Fe(III) as an electron sink. The ability of this extremophile to accumulate poly(3-hydroxybutyrate) (PHB) and secrete extracellular polymeric substances (EPS) has also been reported. Hence, the aim of this work is to characterize the production of PHB and EPS by the wild strain DSM2389 using glycerol in shaken flasks and bioreactor. Results showed that maximum PHB accumulation (37-42% w/w) was obtained using glycerol concentrations of 9 and 15gL-1, where maximum dry cell weight titers reached 3.6 and 3.9gL-1, respectively. The culture in the bioreactor showed that PHB accumulation takes place under oxygen limitation, while the redox potential of the culture medium could be used for online monitoring of the PHB production. Recovered EPS was analyzed by Fourier-transform infrared spectroscopy and subjected to gas chromatography-mass spectrometry after cleavage and derivatization steps. These analyses showed the presence of sugars which were identified as mannose, rhamnose and glucose, in a proportion near to 3.2:2.3:1, respectively. Since glycerol had not been used in previous works, these findings suggest the potential of A. cryptum to produce biopolymers from this compound at a large scale with a low risk of microbial contamination due to the low pH of the fermentation process.

Enhanced photocatalytic degradation of tetracycline by improving electron flux at the Schottky junction between Bi nanoparticles and MoS2-anchored RGO

In this work, a heterostructured metallic Bi/MoS2 photocatalyst (MBix) was prepared via uniform decoration of plasmonic bismuth nanoparticles onto the surface of MoS2 nanosheets. MBix catalysts were then loaded onto the surface of reduced graphene oxide (RGO) using a simple hydrothermal method to form RGO/MBix nanocomposite. RGO/MBix heterostructures demonstrated significantly improved photocatalytic performance for the removal of tetracycline (TC) under visible-light irradiation. The enhanced photocatalytic activity was found to be dependent on the level of Bi and RGO in the catalyst. The degradation rate over the optimum catalyst (RGO-2.5/MBi1.0) was six-fold higher than that of pristine MoS2. The enhanced photocatalytic activity was due to the improved light-harvesting and promoted separation efficiency of carrier pairs through the local surface plasmonic resonance (LSPR) effect of Bi nanoparticles and thus effective electron migration in Bi/MoS2 hetero-interface. Moreover, reduced graphene oxide (RGO) as a supreme electron sink provided a conduction path for excited electrons, and further decreased the rate of electron-hole recombination. The reduced charge recombination was well supported by photoluminescence and electrochemical impedance analyses. The radical trapping experiments indicated that the hydroxyl and superoxide radicals were the main active species to initiate TC degradation. Developing earth-abundant Bi-based photocatalysts, as well as the facile and economical approach to fabricating LSPR-enhanced composite will provide new insights into replacing the noble metals materials for environmental remediation.

A Roll‐to‐Roll Gravure‐Printing System for Manufacturing Near‐Field Energy‐Harvesting Labels

Billions of costless near‐field communication (NFC) sensor labels per day are demanded to practically enable edge computing between smartphones and everyday objects. However, to activate the billions of NFC sensor labels daily, providing an inexpensive manufacturing method for billions of wireless energy‐harvesting labels (WeHL) per day will become a decisive issue for realizing the practical applications. Herein, a roll‐to‐roll (R2R) gravure, a typical high‐throughput additive manufacturing method, is explored to print WeHLs where six diodes and six capacitors are integrated. To meet the high‐throughput manufacturing speed (90 mm s−1) of the R2R gravure system, six different electronic inks are formulated to print the WeHLs to harvest ±10 V from the smartphone's NFC carrier. To attain a practical device yield under the given printing speed, the web tension, nip force, doctor blade angle, and overlay printing registration accuracy are well controlled and optimized to print six different layers within a high overlay printing accuracy, while printing patterns to connect two electrodes with a height difference greater than 3 μm. The fully R2R‐printed WeHLs can successfully harvest energy from the smartphone's NFC carrier with the conversion efficiency of 50%.

Multi-heme cytochrome-mediated extracellular electron transfer by the anaerobic methanotroph ‘Candidatus Methanoperedens nitroreducens’

Anaerobic methanotrophic archaea (ANME) carry out anaerobic oxidation of methane, thus playing a crucial role in the methane cycle. Previous genomic evidence indicates that multi-heme c-type cytochromes (MHCs) may facilitate the extracellular electron transfer (EET) from ANME to different electron sinks. Here, we provide experimental evidence supporting cytochrome-mediated EET for the reduction of metals and electrodes by ‘Candidatus Methanoperedens nitroreducens’, an ANME acclimated to nitrate reduction. Ferrous iron-targeted fluorescent assays, metatranscriptomics, and single-cell imaging suggest that ‘Ca. M. nitroreducens’ uses surface-localized redox-active cytochromes for metal reduction. Electrochemical and Raman spectroscopic analyses also support the involvement of c-type cytochrome-mediated EET for electrode reduction. Furthermore, several genes encoding menaquinone cytochrome type-c oxidoreductases and extracellular MHCs are differentially expressed when different electron acceptors are used.

Design of an Autonomous IoT Node Powered by a Perovskite-Based Wave Energy Converter

Abstract This paper presents the results of experimental research focused on wave energy harvesting and its conversion to power Internet of Things (IoT) devices. The harvesting and conversion process was performed using a wave energy converter (WEC) consisting of a lead zirconate titanate piezoelectric ceramic perovskite material and a prototype power electronic circuit. The designed WEC was considered as a power supply for an end node device (END) of an IoT network. The END consisted of a long-range radio module and an electronic paper display. A set of physical experiments were carried out, and the results confirmed that an energy surplus was supplied by WEC compared to the energy consumed by the END. Hence, the proposed scheme was experimentally validated as a convenient solution that could enable the autonomous operation of an IoT device. The use case presented here for the proposed WEC was analysed for selected sea areas on the basis of wave statistics. The novelty of this paper arises from an investigation that confirms that WECs can significantly contribute to the development of wireless and mobile IoT communication powered by freely available sea wave energy.

Correlation between the rheology of electronic inks and the droplet size generated from a capillary nozzle in dripping regime

This study provides a complete rheological characterization of bidimensional (2D) nanomaterial dispersions, employed as 2D-inks precursors in printed electronics. Three different 2D nanomaterials [molybdenum disulfide (MoS2), graphene, and hexagonal boron nitride (hBN)] were dispersed in a Newtonian fluid (toluene) and a viscoelastic fluid (toluene + ethyl cellulose) with different polymer concentrations. The presence of nanosheets does not change the shear rheology of the carrier fluid. Regarding the extensional rheology, the results showed that the pinch-off phenomenon is present in all toluene suspensions; however, the presence of the ethyl cellulose introduces elasticity in the system, even leading to the formation of beads-on-a-string, and the relaxation times of the suspensions depend on the kind of nanosheets present in the fluid. As controlling the droplet size when dispensing 2D-inks is of paramount importance for printed electronics as well as for many other applications, here it is presented a correlation between the rheological properties of these 2D-inks precursors and their droplet size when generated from a capillary nozzle in the dripping regime.

Efficient hydrogen production in single-chamber microbial electrolysis cell with a fermentable substrate under hyperalkaline conditions

Hydrogen production from food waste is of great significance for energy conversion and pollution control. The aim of this study was to investigate the glucose fermentation from food waste and hydrogen (H2) production in the single-chamber microbial electrolysis cell (MEC) under hyperalkaline conditions. Single-chamber MECs were tested with 1 g/L glucose as substrate under different pH values (i.e., 7.0, 9.5, and 11.2) and applied voltages (i.e., 0.8, 1.2, and 1.6 V). With pH increase from 7.0 to 11.2, H2 production with methanogenesis inhibition was significantly improved in the MEC. At pH of 11.2, the maximum current density reached 180 ± 9 A/m3 with the H2 purity of 93.3 ± 1.2% and average H2 yield of 7.72 ± 0.23 mol H2/ mol glucose under 1.6 V. Acetate from glucose fermentation was the largest electron sink within 12 h. Methanobacterium alcaliphilum dominated the archaeal communities with the relative abundance of > 99.0% in the cathodic biofilms. The microbial communities and mcr A gene copy numbers analyses showed that high pH enhanced the acetate production from glucose fermentation, inhibited syntrophic acetate-oxidizing with hydrogenotrophic methanogenesis in the anodic biofilms, and inhibited hydrogenotrophic methanogenesis in the cathodic biofilms. Our results of hyperalkaline conditions provide a feasible way to harvest H2 efficiently from fermentable substrates in the single-chamber MEC.

Influence of the ambipolar field on the formation of electron phase flows in the positive column of a glow discharge in a nitrogen-like gas

The formation of the electron energy distribution function (EEDF) and phase flows of electrons in the plasma of a positive column of a glow discharge in a model gas with strong vibrational excitation, similar to molecular nitrogen, is analyzed in a wide pressure range. It is found that the traditional local approximation for calculating the EEDF can only be used at medium gas pressures, when the characteristic size of the plasma volume exceeds electron energy relaxation length in the entire range of electron energies. With a decrease in gas pressure, a new phenomenon is discovered—merging the phase flow streamlines into a single line on the coordinate-energy phase plane in the energy region of the of vibrational excitation threshold. It is shown that the combination of a strong electron sink at the threshold of vibrational excitation and the deceleration of electrons in an ambipolar field lead to a practical ‘vanishing’ of the component of the phase electron flux upward in energy. As a result, the streamlines of electron phase flow approach to some approximately straight line of constant kinetic energy close to the threshold energy of vibrational excitation. The formation of this feature on the phase plane correlates with the predominant escape to the walls of electrons with kinetic energy equal to the threshold of vibrational excitation.

(Invited) inkjet-Printed Soft Electronic Devices and Sensors for Wearable Health Monitoring Applications

Stretchable electronic devices and sensors built on thin elastomer substrates may find a wide range of applications in wearable health monitoring devices owing to their ability to conformably adapt to human skin for long-term and comfortable wearing. In this talk, I will present our work on developing intrinsically-stretchable electronic materials that are formulated as electronic inks and patterend using a highly scalable and low-cost inkjet printing process. A variety of soft sensors including silver nanoparticle based ultrasensitive resistive strain sensor and pressure sensor, porous elastomer dielectric based capacitive pressure sensor, and multimodal sensor that can differentiate pressure, strain, and temperature stimuli have all been demonstrated on ultrathin polydimethylsiloxane (PDMS) substrate by printing. These devices have been used in applications including motion and gesture tracking, voice recognition, arterial pulse waveform and photoplethysmogram monitoring. In addition, I will also report our work on the development of a unique porous PDMS sponge electrode as a gel-free dry interface for motion-artifact tolerant recording of electrophysiological signals. The porous structure of the soft electrode significantly increases the effective contact area and lowers the electrode-skin impedance, which result in improved signal-to-noise ratio. Compared to commercial rigid electrodes, the soft and thin form factor also makes the spongy electrode well-suited for long-term recording of high quality biopotential signals including electrocardiogram (ECG) and electromyography (EMG) on ambulatory patients. As a demonstration of its clinical usage with a focus on maternal and fetal health monitoring, I will show an array of such soft electrodes integrated on a printed patch of textile-based interconnections, and used for recording and spatiotemporal mapping of the uterine contraction patterns from patients in active labor.

Selectively oxygen reduction reaction and strongly suppressed CO poisoning on PtZn nanoalloys decorated on N-doped carbon sphere

The development of a high-performance oxygen reduction reaction (ORR) catalyst with a low Pt content, high activity, and long-term durability is crucial as it can become a core item in the fuel cell market. In this study, the amount of Pt used in the catalyst is reduced by more than three-fold compared with commercial catalysts. Concurrently, a PtZn alloy, which does not use expensive transition metals, is introduced as an active species. Nitrogen-doped carbon sphere (CS), which serves as an electron sink, is used as a support; it acts as a Lewis base site and facilitates H+ adsorption during the ORR. The analytical results reveal that the introduction of Zn is significantly more favorable for the ORR compared with N-doping. O2-pulse temperature-programmed desorption (TPD) reveals that most of the O2 molecules are adsorbed on Zn, and CO-pulse TPD demonstrates that Zn suppresses CO poisoning in the PtZn alloys. The mass and specific activities of the Pt1Zn1/N-CS electrode at 0.9 V are 5.94 A mg–1 and 0.79 mA cm–2, respectively, and a rotational frequency of 2.5 e-site–1 s–1 is achieved. The electrochemical performance remains unchanged even after 5000 cycles. The ORR on the Pt1Zn1/N-CS electrode does not occur randomly on Pt and Zn; Pt and Zn selectively attract and reduce *O, *OH, or *OOH which generated as intermediates.

Biochemical characterization of patients with dihydrolipoamide dehydrogenase deficiency.

Dihydrolipoamide dehydrogenase (DLD; E3) oxidizes lipoic acid. Restoring the oxidized state allows lipoic acid to act as a necessary electron sink for the four mitochondrial keto-acid dehydrogenases: pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, branched-chain α-keto-acid dehydrogenase, and 2-oxoadipate dehydrogenase. DLD deficiency (DLDD) is caused by biallelic pathogenic variants in DLD. Three major forms have been described: encephalopathic, hepatic, and myopathic, although DLDD patients exhibit overlapping phenotypes. Hyperlactatemia, hyperexcretion of tricarboxylic acid cycle (TCA) metabolites and branched-chain keto acids, increased plasma branched-chain amino acids and allo-isoleucine are intermittent metabolic abnormalities reported in patients with DLDD. However, the diagnostic performance of these metabolites has never been studied. Therefore, we sought to systematically evaluate the diagnostic utility of these biomarkers for DLDD. We retrospectively analyzed the results of biochemical testing of six unrelated DLDD patients, including values obtained during both well visits and acute decompensation episodes. Elevation of branched-chain amino acid concentrations was not consistently observed. We found that five of six patients in our cohort had a maximum lifetime value of allo-isoleucine of 6 μmol/L, showing that alloisoleucine elevations even during illness may be subtle. Urine organic acid analysis (UOA) during acute decompensation episodes was abnormal in all cases; however, the pattern of abnormalities had high intersubject variability. No single biomarker was universally present, even in patients experiencing metabolic decompensation. We also observed novel biochemical associations: three patients had hyperexcretion of TCA cycle metabolites during crisis; in two patients, 2-ketoadipic and 2-hydroxyadipic acids, by products of lysine degradation, were detected. We propose that these result from 2-oxoadipate dehydrogenase deficiency, an underappreciated biochemical abnormality in DLD. Given the diversity of biochemical profiles among the patients with DLDD, we conclude that accurate biochemical diagnosis relies on a high index of suspicion and multipronged biochemical analysis, including both plasma amino acid and urine organic acid quantitation during decompensation. Biochemical diagnosis during the well state is challenging. We emphasize the critical importance of multiple simultaneous biochemical tests for diagnosis and monitoring of DLDD. We also highlight the under-recognized role of DLD in the lysine degradation pathway. Larger cohorts of patients are needed to establish a correlation between the biochemical pattern and clinical outcomes, as well as a genotype-phenotype correlation.

High-Performance Flexible Graphene Oxide-Based Moisture-Enabled Nanogenerator via Multilayer Heterojunction Engineering and Power Management System.

Recently, there has been a surge of interest in nanogenerators within the scientific community because their immense potential for extracting energy from the surrounding environment. A promising approach involves utilizing ambient moisture as an energy source for portable devices. In this study, moisture-enabled nanogenerators (MENGs) are devised by integrating heterojunctions of graphene oxide (GO) and reduced graphene oxide (rGO). Benefiting from the unique structure, a larger ion concentration gradient is achieved as well as a lower resistance, which leads to enhanced electricity generation. The resulting MENG generates a desirable open-circuit voltage of 0.76V and a short-circuit current density of 73 µAcm-2 with a maximum power density of 15.8 µWcm-2. Notably, the designed device exhibits a high voltage retention of more than 90% after 3000 bending cycles, suggesting a high potential for flexible applications. Moreover, a large-scale integrated MENG array is developed by incorporating flexible printed circuit technology and connecting it to a power management system. This integrated system can provide ample energy to operate an electronic ink display and drive a heart rate sensor for health monitoring. The outcomes of this research present a novel framework for advancing next-generation self-powered flexible devices, thereby demonstrating significant promise for future wearable electronics.

Dual‐Site Activation Coupling with a Schottky Junction Boosts the Electrochemiluminescence of Carbon Nitride

AbstractRobust electrochemiluminescence (ECL) of carbon nitride (CN) requires efficient electron‐hole recombination and the suppression of electrode passivation. In this work, Au nanoparticles and single atoms (AuSA+NP) loaded on CN serve as dual active sites that significantly accelerate charge transfer and activate peroxydisulfate. Meanwhile, the well‐established Schottky junctions between Au NPs and CN act as electron sinks, effectively trapping over‐injected electrons to prevent electrode passivation. As a result, the porous CN modified with AuSA+NP exhibits an enhanced and stable ECL emission, with a minimal relative standard deviation of 0.24 %. Furthermore, the designed ECL biosensor based on AuSA+NP‐CN shows a remarkable performance in detecting organophosphorus pesticides. This innovative strategy has the potential to offer new insights into strong and stable ECL emission for practical applications.

Dual-Site Activation Coupling with a Schottky Junction Boosts the Electrochemiluminescence of Carbon Nitride.

Robust electrochemiluminescence (ECL) of carbon nitride (CN) requires efficient electron-hole recombination and the suppression of electrode passivation. In this work, Au nanoparticles and single atoms (AuSA+NP ) loaded on CN serve as dual active sites that significantly accelerate charge transfer and activate peroxydisulfate. Meanwhile, the well-established Schottky junctions between Au NPs and CN act as electron sinks, effectively trapping over-injected electrons to prevent electrode passivation. As a result, the porous CN modified with AuSA+NP exhibits an enhanced and stable ECL emission, with a minimal relative standard deviation of 0.24 %. Furthermore, the designed ECL biosensor based on AuSA+NP -CN shows a remarkable performance in detecting organophosphorus pesticides. This innovative strategy has the potential to offer new insights into strong and stable ECL emission for practical applications.

Surface microstructure modulation boosting electron transfer between Pt clusters and carbon nitrogen for effective photocatalysis

Tuning the microstructure of the catalyst surface is crucial for the loading of the co-catalyst, especially influencing the electron transfer and the size of the co-catalyst. However, influence of co-catalyst loading, related to the surface structure of the catalysts, is largely ignored. Here in, nitrogen vacancies were introduced to regulate the microstructure of carbon nitrogen and using this amorphous carbon nitride (ACN) with nitrogen vacancies as a substrate to provide atomic anchoring sites as well as electron sink to prevent Pt from further agglomeration. Experimental and theoretical results show that nitrogen vacancies were electron acceptors, which beneficial to reduce [PtCl6]2− by photo-generated electrons and consequently stabilize Pt ultra-small clusters located on the ACN. Furthermore, by combing structure and carrier behaviors, we infer that Pt ultra-small clusters stable location comes from the strong interaction between Pt and nitrogen vacancies. Pt ultra-small clusters improve electron transfer and boost photocatalytic hydrogen production. A delicate design modulates the catalyst microstructure to enhance interaction between the catalyst and the co-catalyst, resulting in a smaller co-catalyst size and provides a mean to create and optimize small size Pt-loaded and highly active photocatalysts.

Expansion of Armatimonadota through marine sediment sequencing describes two classes with unique ecological roles

Marine sediments comprise one of the largest environments on the planet, and their microbial inhabitants are significant players in global carbon and nutrient cycles. Recent studies using metagenomic techniques have shown the complexity of these communities and identified novel microorganisms from the ocean floor. Here, we obtained 77 metagenome-assembled genomes (MAGs) from the bacterial phylum Armatimonadota in the Guaymas Basin, Gulf of California, and the Bohai Sea, China. These MAGs comprise two previously undescribed classes within Armatimonadota, which we propose naming Hebobacteria and Zipacnadia. They are globally distributed in hypoxic and anoxic environments and are dominant members of deep-sea sediments (up to 1.95% of metagenomic raw reads). The classes described here also have unique metabolic capabilities, possessing pathways to reduce carbon dioxide to acetate via the Wood-Ljungdahl pathway (WLP) and generating energy through the oxidative branch of glycolysis using carbon dioxide as an electron sink, maintaining the redox balance using the WLP. Hebobacteria may also be autotrophic, not previously identified in Armatimonadota. Furthermore, these Armatimonadota may play a role in sulfur and nitrogen cycling, using the intermediate compounds hydroxylamine and sulfite. Description of these MAGs enhances our understanding of diversity and metabolic potential within anoxic habitats worldwide.

Carbon dots driven directional charge migration on sulfur vacancy enriched ZnIn2S4 nanosheets for enhanced photocatalytic hydrogen evolution

Sulfur vacancy as a kind of intrinsic defect for metal sulfides plays an important role in adjusting the electronic structure, but the uncontrollability of the regulation does not always lead to efficient activity in photocatalytic hydrogen production. To address this issue, a photocatalytic nanocomposite is designed and constructed by in situ inserting carbon dots (CDs) into ultrathin ZnIn2S4 (ZIS) nanosheets with sulfur vacancies (CDs/Vs-ZIS) by a one-step hydrothermal method. The charge transfer kinetics analysis of CDs/Vs-ZIS demonstrates that the trapped electrons by sulfur vacancies are directed transferred to the surface of CDs. The electron sink effect leads to further enhancement of the charge separation efficiency on CDs surface and CDs act as hydrogen-producing active sites to greatly improve the hydrogen evolution. Benefiting from the directional charge migration driven by CDs in Vs-ZIS nanosheets, the optimal CDs/Vs-ZIS photocatalyst exhibits a superior photocatalytic hydrogen evolution rate of 5.93 mmol g−1h−1.