One way to expand online seafood sales is to extract information about products and services from online posts left by consumers and use it as a hint for improving products and services. However, ...there has not been enough research on collecting many online posts about seafood sales services and extracting information efficienst- ly. The purpose of this paper was to analyze online consumers' opinions about seafood sales services using a topic model and to obtain suggestions that will lead to the use of online sales of seafood by more consumers. The data were collected from three online services related to S, a seafood sales service that operates multiple stores and e-commerce sites in Tokyo. First, morphological analysis was conducted on all the data. Then, a set number of topics were extracted using Gensim, a library of Python, and assigned meanings. As a result, it was suggested that to encourage more consumers to use online seafood sales services free from anxiety and mistrust, it is important to adjust expectations for the quality of marine foods so that they do not deviate too much from the actual situation.
•Ce-doped SnS QDs/SnS2 nanocomposites were prepared by a facile one-step hydrothermal method for room-temperature gas sensors.•Experimental analysis revealed that single atom Ce can preferentially ...combine with SnS to form Sn-S-Ce bond to hinder the growth and oxidation of SnS quantum dots.•By optimizing the Ce doping ratio, the amount and size of SnS quantum dots on the surface of SnS2 nanosheets can be regulated to obtain an ideal heterostructure, can improve the gas-sensing performance.
Metal sulfide-based gas sensors have the advantage of high sensitivity at room temperature, enabling high integration and low power consumption. However, a trade-off between low baseline resistance and good long-term stability at room temperature still needs to be addressed. Therefore, a single-atom Ce-targeted regulation strategy for p-SnS/n-SnS2 was proposed. By doping different amounts of Ce, the amount and size of SnS quantum dots on the surface of SnS2 can be regulated. Furthermore, Sn-S-Ce bonds are formed by combining single-atom Ce with SnS, which effectively hinders the growth and oxidation of SnS quantum dots, as evidenced by STEM, XPS, DFT, FTIR and EAXFS methods. Due to the unique energy band structure of p-SnS and n-SnS2, Ce-doped SnS quantum dots serve as electronic sensitizers, effectively increasing the carrier concentration in SnS2. The optimal gas sensor based on the 1% Ce-doped SnS/SnS2 composites enables high sensitivity (with a response of 22.1 to 1 ppm NO2), ultralow detection limit (1 ppb), excellent long-term stability at room temperature, and a lower baseline resistance. This engineering strategy of metal sulfide semiconductor heterostructures through single-atom targeted regulation provides new insights for further optimizing the composite system.
In an always connected communication environment, users of social networking services (SNSs) need to pay continuous attention to the overwhelming volume of social demands from SNSs. These increased ...energy requirements may cause SNS fatigue, which can lead to physical and psychological strain. Using the transactional theory of stress and coping as the overarching theory, this study regards overload (i.e., stressors) as a core determinant of SNS fatigue (i.e., strain) and identifies three dimensions of overload – information overload, communication overload, and system feature overload. It also includes SNS characteristics as the antecedents of overload.
The data used in this study were collected from 201 individuals through online and offline surveys. Our results show that all three dimensions of overload were significant stressors that influence SNS fatigue. Regarding the predictors of overload, the characteristics of the SNS system significantly influenced the features of system overload, while information equivocality positively influences information overload. However, information relevance was not a significant predictor of information overload and information equivocality was not a significant predictor of communication overload.
•We examine SNS fatigue as an outcome of the stress process.•Three dimensions of overload are significant stressors influencing SNS fatigue.•Information and system characteristics of SNSs are determinants of overload.
Abstract
ZnS has been found superiority in photoelectrochemistry for the fast response of photo‐inducing and its high conductor band position (~0.8 eV) results in strong reduction ability for ...hydrogen production. However, the solar absorbance of ZnS is much low for the wide band gap (~3.2 eV) and the carriers’ migration efficiency also need to be improved. Here, nano‐ZnS were coupled with ultrathin SnS
2
nanosheets as heterojunction composites. This heterojunction composite demonstrated largely increase in specific surface area (from 4 to 12‐25 m
2
/g), obvious improvement of
UV
‐vis absorbance and narrower band gap. Furthermore, the carriers’ migration efficiency of ZnS/SnS
2
heterojunction has been confirmed to be much higher by photocurrent response and electrochemical impedance spectroscopy. Due to the improvement in structure, compared with pristine ZnS, this ZnS/SnS
2
heterojunction exhibited vast enhancement in photoelectrochemical performance. The composite with best activity exhibited 12.8 times enhancement in photocurrent density. The conduction band and valence band of ZnS are both more negative than those of SnS
2
, the photo‐induced electrons at the conduction band of ZnS will transfer into the conduction band of SnS
2
while the photo‐induced holes at the valence band of SnS
2
will transfer into the valence band of ZnS. In this way, the photo‐produced carriers will flow into different semiconductors and the carriers’ migration efficiency is enhanced. The work improves a new structure to develop the heterojunction property for photoelectrochemical application.
•Novel SnS2/SnS/N-CNO composite was syntheiszed by solvothermal and pyrolysis methods.•Heterostructured SnS2/SnS/N-CNO improves conductivity and electrochemical performance.•SnS2/SnS/N-CNO electrode ...delivered superior specific capacitance of 741.67 F g−1.•SnS2/SnS/N-CNO showed excellent cycling stability (95%) retention after 2000 cycles.•Heterostructured composite electrode exhibited excellent power and energy densities.
The unique properties of the Sn-S system made it a high sensitiveness nanomaterial for prepare higher-performance supercapacitors. The heterostructured SnS2/SnS and N-CNOs were synthesized by simple solvothermal and pyrolysis methods, respectively. To improve the conductivity of the SnS2/SnS composite, N-CNOs were added to the pristine SnS2/SnS. Herein, an ultrasensitive supercapacitor based on SnS2/SnS and N-CNOs was fabricated. Compared to the pristine SnS2/SnS heterostructured composite, SnS2/SnS/N-CNO showed high supercapacitance performance due to the increase in conductivity with the addition of C-based N-CNOs. Regarding that SnS2/SnS/N-CNO has superior electrochemical performances comparable to SnS2/SnS, because of the fast electronic transportations and volume changes in the formations of SnS2/SnS/N-CNO heterostructures. The electrochemical performance of the SnS2/SnS/N-CNO electrode enhanced specific capacitance value of 741.67 F g−1 from SnS2/SnS electrode specific capacitance of 350 F g−1 at a 0.5 A g−1 and it showed excellent cycling stabilities of 95% retention even after 2000 cycles. The obtained results suggest that the SnS2/SnS/N-CNO is efficient to be applicable as a novelelectro-active sourcein supercapacitor devices to render higher performances and stable energy storage applications.
Urchinlike SnS/SnS2 p-n heterogeneous composite photocatalysts were successfully synthesized by a one-step solvothermal method. The samples are characterized by XRD, XPS, SEM, TEM, BET and DRS. ...SnS/SnS2 (Sn/S=39.87:60.13) heterostructure exhibited the higher photocatalytic activity, the removal efficiency of MO was 83.25% in illuminate 60min, and degradation reaction was calculated by adopting the pseudo-first-order reaction kinetics, the k value was 3.351×10−2min−1 which was higher than pure SnS and pure SnS2 under visible light irradiation. The mechanism of enhanced photocatalytic activity has been discussed through scavenger experiments. In addition, the main active species for degradation of methyl orange (MO) were investigated using electron spin resonance (ESR) measurement and the possible degradation pathway of MO was also presented.
•Urchinlike SnS/SnS2 p-n heterogeneous composites were successfully synthesized.•Using a one-step solvothermal method.•SnS/SnS2 as a promising photocatalyst on the degradation of methyl orange (MO).•The stability of SnS/SnS2 and the photodegradation mechanism of MO were studied.•The possible degradation pathway of MO was also presented.
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•A novel double heterojunction of CdS-SnS-SnS2 supported on rGO was synthesized.•CdS-SnS-SnS2/rGO showed enhanced photocatalytic activity and durability.•rGO as an electron carrier ...facilitated the migration of photogenerated charge.•The double heterojunction efficiently suppressed fast electron-hole recombination.
In this work, a novel CdS-SnS-SnS2/rGO photocatalyst with two tin valence states (Ⅱ and IV) was successfully synthesized by a one-pot solvothermal method. For comparison, CdS-SnS2/rGO (GCS2) with tin in only the IV valence state was made by the same method. Based on a series of characterizations, CdS, SnS and SnS2 were shown to be successfully loaded onto the rGO surface. The introduction of rGO may increase charge carrier separation. The degradation efficiency increased gradually with increasing rGO loading content, and the optimum photocatalytic activity was observed at 6.0 wt% rGO loading content (GCS1), which achieved the efficient removal (84.46%) of ibuprofen over 60 min. Compared with GCS2, the CdS-SnS-SnS2/rGO composite exhibited significantly improved photocatalytic performance, which can be ascribed to the formation of a double heterostructure. rGO worked as a transfer mediator to transfer electrons from the conduction band (CB) of SnS to the CB of SnS2 at the heterointerface, which then flowed to the CB of CdS because of another heterojunction, further enhancing the separation efficiency of photogenerated carriers. Therefore, this study highlights a novel double heterojunction system with a facial preparation method, visible light response and good recyclability, which is beneficial for environmental remediation.
Current application of SnS2-based anodes in sodium-ion batteries fails to meet the demand for higher Na+ storage capacity due to the structural pulverization induced by significant volume changes ...during cycling. Herein, a novel composite of hollow C@SnS2/SnS@C cubes with excellent diffusion kinetics and structural stability from stepwise Na+ storage is designed. The SnS with gentle pseudocapacitive reaction acts as the self-supporter to prevent the collapse of SnS2/SnS heterostructure during the Na+ insertion/extraction. Together with the clamping of double carbon layers and hollow construction, the volume change caused structural instability in heterostructure is effectively alleviated. The rapid transport of electrons and ions within the built-in electric field of heterostructure endows the composite an excellent diffusion kinetics, which is generated from the narrow bandgap and outstanding Na+ absorption of heterostructure according to the first-principle calculation. Thus, the as-prepared composite maintains a remarkable capacity of 547.9 mAh g−1 after 200 cycles at current density of 0.5 A g−1. Even a capacity of 502.5 mAh g−1 with a low attenuation rate of 0.035 % per cycle is achieved at 2 A g−1 after 1000 cycles. The work proposes an effective approach to achieve effective Na + storage of SnS2-based anodes with long-lasting structural stability.
•A novel hollow SnS2/SnS heterostructure clamped with carbon layers was designed.•The SnS self-support and hollow carbon layers provide a stable structure.•The electric field within in heterostructure enhances the diffusion kinetics.•Remarkable capacity of 547.9 mAh·g−1 was remained at 0.5 A g−1 after 200 cycles.
Nanostructured-alloy-type anodes have received great interest for high-performance lithium-ion batteries (LIBs). However, these anodes experience huge volume fluctuations during repeated ...lithiation/delithiation and are easily pulverized and subsequently form aggregates. Herein, an efficient method to stabilize alloy-type anodes by creating defects on the surface of the metal oxide support is proposed. As a demonstration, PPy-encapsulated SnS
nanosheets supported on defect-rich TiO
nanotubes were produced and investigated as an anode material for LIBs. Both experimental results and theoretical calculations demonstrate that defect-rich TiO
provides more chemical adhesions to SnS
and discharge products, compared to defect-poor TiO
, and then effectively stabilizes the electrode structure. As a result, the composite exhibits an unprecedented cycle stability. This work paves the way to designing durable and active nanostructured-alloy-type anodes on oxide supports.
Developing efficient heterojunction electrocatalysts and uncovering their atomic‐level interfacial mechanism in promoting sulfur‐species adsorption‐electrocatalysis are interesting yet challenging in ...lithium‐sulfur batteries (LSBs). Here, multifunctional SnS2‐MXene Mott–Schottky heterojunctions with interfacial built‐in electric field (BIEF) are developed, as a model to decipher their BIEF effect for accelerating synergistic adsorption‐electrocatalysis of bidirectional sulfur conversion. Theoretical and experimental analysis confirm that because Ti atoms in MXene easily lost electrons, whereas S atoms in SnS2 easily gain electrons, and under Mott–Schottky influence, SnS2‐MXene heterojunction forms the spontaneous BIEF, leading to the electronic flow from MXene to SnS2, so SnS2 surface easily bonds with more lithium polysulfides. Moreover, the hetero‐interface quickly propels abundant Li+/electron transfer, so greatly lowering Li2S nucleation/decomposition barrier, promoting bidirectional sulfur conversion. Therefore, S/SnS2‐MXene cathode displays a high reversible capacity (1,188.5 mAh g−1 at 0.2 C) and a stable long‐life span with 500 cycles (≈82.7% retention at 1.0 C). Importantly, the thick sulfur cathode (sulfur loading: 8.0 mg cm−2) presents a large areal capacity of 7.35 mAh cm−2 at lean electrolyte of 5.0 µL mgs−1. This work verifies the substantive mechanism that how BIEF optimizes the catalytic performance of heterojunctions and provides an effective strategy for deigning efficient bidirectional Li‐S catalysts in LSBs.
The authors design a SnS2‐MXene Mott–Schottky heterojunction catalyst with built‐in electric field (BIEF), and the formation mechanism of BIEF, BIEF effect, and atomic‐level manipulation mechanism for accelerating adsorption‐electrocatalysis of bidirectional sulfur conversion are uncovered. The obtained S/SnS2‐MXene cathode displays a long‐life span with 500 cycles and a large areal capacity at lean electrolyte.
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