Hexagonal CdS assembled with lamellar NiCo LDH form S-scheme heterojunction for photocatalytic hydrogen evolution

doi:10.1016/j.mssp.2021.106128

Materials Science in Semiconductor Processing

Volume 135, 15 November 2021, 106128

https://doi.org/10.1016/j.mssp.2021.106128 Get rights and content

Highlights

•
An S-scheme heterojunction composed of CdS and NiCo LDH was formed.
•
The recombination of photoinduced electron-hole pairs was inhibited.
•
Highly improved photocatalytic hydrogen evolution activity was obtained.
•
Hydrogen evolution performance is 3.6 times the of CdS.

Abstract

Hexagonal CdS and layered double hydroxides are the hot materials for photocatalytic hydrogen evolution reaction due to their unique structure and excellent performance. Here, CdS/NiCo LDH catalyst with S-scheme heterogeneous is successfully prepared by the method of electrostatic self-assembly. Compared with CdS, the hydrogen evolution performance over the appropriate CdS/NiCo LDH is increased by 3.6 times. This is because the tight coupling of the contact interface between CdS and NiCo LDH and the matching of the band gap structure improve the transmission efficiency of photogenerated electrons. Ultraviolet–visible and photoluminescence experiments have proved that the separation efficiency of electrons and holes, the light absorption intensity and the charge lifetime of the composite catalyst have been greatly improved. Additional series of characterization prove the possible S-scheme heterojunction mechanism of CdS/NiCo LDH photocatalytic hydrogen evolution.

Graphical abstract

Introduction

With the increasing global warming and fossil energy crisis, people are paying more and more attention to the search for renewable clean energy [1,2]. Solar and hydrogen energy are the kind of sustainable energy. Photocatalytic technology can convert solar energy into hydrogen energy [[3], [4], [5]]. In recent years, the use of semiconductor materials to split water to produce hydrogen under light has been a hot topic of research [6,7]. How to prepare excellent semiconductor catalysts to improve the separation efficiency of photogenerated carriers is the topic of current research. To achieve this great long-term goal, after years of hard work, people have worked together to develop semiconductor catalytic materials to improve the hydrogen evolution reaction [[8], [9], [10]].

With the increasing advancement of technology, more and more photocatalysts have been developed, for example, g-C₃N₄ TiO₂ CdS and so on. CdS is a low-cost and easy-to-prepare catalyst that exhibits excellent performance under visible light [[11], [12], [13], [14]]. Therefore, CdS is widely used by researchers in the field of photocatalysis. However, CdS has a serious photo-corrosion phenomenon, resulting in low photo-generated carrier separation efficiency. Hao's group prepared hexagonal CdS single crystals to improve the hydrogen evolution performance by changing the ratio of CdS precursors [15]. Layered Double Hydroxide (LDH) is a collective term for Hydrotalcite (HT) and Hydrotalcite-Like Compounds (HTLCs), a series of supramolecular materials intercalated and assembled by these compounds known as hydrotalcite-like intercalation materials (LDHs) [16]. Hydrotalcite materials are anionic layered compounds. Its chemical formula is [M²⁺_1-xM³⁺_x(OH)₂(^An-_x/n)]·yH₂O, M²⁺ is a divalent metal cation, M³⁺ is a trivalent metal cation, A^n- is an anion, and x is the molar ratio of M²⁺ to M^3+. The cations in LDHs are adjustable, the anions are exchangeable. For instance, the efficient H₂ evolution was got by anchoring CoAl LDH nanosheets on NiTiO₃ [17]. B-doping-induced amorphization of LDH for large-current-density hydrogen evolution reaction [18]. LDHs have low hydrogen evolution performance due to their poor structure.

Since a single catalyst exhibits poor catalytic performance, people began to study composite heterogeneous structure catalysts to improve catalytic performance [19,20]. To address recombination of photogenerated electrons and holes, a method of constructing a heterojunction including p-n, type-II, Z-scheme and S-scheme heterojunction can be adopted [21]. The conception of S-scheme heterojunction, which possesses strong redox ability, is come up by Yu’s group [[22], [23], [24], [25]]. In this paper, a new S-scheme heterojunction is constructed by loading hexagonal CdS single crystals on NiCo LDH to improve the performance of photocatalytic hydrogen evolution.

Section snippets

The synthesis method of NiCo LDH

Dissolve 0.28g NiCl₂·6H₂O, 0.28g CoCl₂·6H₂O, 0.644g NH₄Cl, and 0.22g NaOH in 40 mL deionized water. After uniformly dispersed by ultrasonic, package them in a 100 mL beaker and continue the reaction at 55°C for 15 h. When the reaction is over, cool the catalyst temperature to 20 °C, washed repeatedly with ethanol and deionized water, the precipitate was separated by ultrasonic centrifugation and dried overnight, the dried powder materials were collected in a mortar [26].

Preparation of CdS

Putting 3.08g Cd(NO₃)₂·4H

XRD analysis

The crystals of the prepared catalyst were analyzed by XRD. In Fig.1a, the a = 4.139 Å and c = 6.720 Å lattice constant is seen from CdS (JCPDS#41–1049). These strong peaks represent the high crystallinity of CdS. The different diffraction peaks of NiCo LDH are located at 11.4^o, 22.7^o, 33.8^o, 39.1^o and 60.22^o correspond to the (003), (006), (009), (015), and (110) of the hydrotalcite-like NiCo LDH phase (JCPDS#89–460) [[26], [27], [28]]. The XRD diffraction peaks of NiCo LDH are similar to

Conclusion

In summary, CdS and NiCo LDH successfully constructed a new S-scheme catalyst CNC-5% through the electrostatic self-assembly method. Compared with CdS, the load of NiCo LDH increases the specific surface area, improves the photocatalytic hydrogen evolution activity, increases the segmentation efficiency of photoproduction holes and electrons and the life of electrons, reduces the electron transfer resistance, and provides more reaction activity. The research of this experiment provides novel

Author contributions

Guoping Jiang and Chaoyue Zheng conceived and designed the experiments; Chaoyue Zheng performed the experiments; Zhiliang Jin contributed reagents/materials and analysis tools; Chaoyue Zheng wrote the paper.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

This work was financially supported by the Natural Science Foundation of Ningxia Province (2020AAC02026).

References (43)

Yuexiang Li et al.
A new concept: volume photocatalysis for efficient H₂ generation-Using low polymeric carbon nitride as an example
Appl. Catal. B Environ.
(2020)
Jie Xiong et al.
CN/rGO@BPQDs high-low junctions with stretching spatial charge separation ability for photocatalytic degradation and H₂O₂ production
Appl. Catal. B Environ.
(2020)
Yuexiang Li et al.
Ni-B coupled with borate-intercalated Ni(OH)₂ for efficient and stable electrocatalytic and photocatalytic hydrogen evolution under low alkalinity
Chem. Eng. J.
(2020)
Xinwei Jiang et al.
In situ construction of NiSe/Mn_0.5Cd_0.5S composites for enhanced photocatalytic hydrogen production under visible light
Appl. Catal. B Environ.
(2020)
Chenchen Feng et al.
Ultrathin graphitic C₃N₄ nanosheets as highly efficient metal-free cocatalyst for water oxidation
Appl. Catal. B Environ.
(2017)
Liangliang Zhu et al.
Fabrication of wheat grain textured TiO2/CuO composite nanofibers for enhanced solar H2 generation and degradation performance
Nano Energy
(2015)
Lei Su et al.
Hemispherical shell-thin lamellar WS₂ porous structures composited with CdS photocatalysts for enhanced H₂ evolution
Chem. Eng. J.
(2020)
Xuqiang Hao et al.
Self-constructed facet junctions on hexagonal CdS single crystals with high photoactivity and photostability for water splitting
Appl. Catal. B Environ.
(2019)
Jue Hu et al.
Nanohybridization of MoS₂ with layered double hydroxides efficiently synergizes the hydrogen evolution in alkaline media
Joule
(2017)
Hongyuan Yang et al.
B-doping-induced amorphization of LDH for large-current-density hydrogen evolution reaction
Appl. Catal. B Environ.
(2020)

Liuyong Chen et al.

Template-free synthesis of carbon-doped boron nitride nanosheets for enhanced photocatalytic hydrogen evolution

Appl. Catal. B Environ.

(2019)

Quanlong Xu et al.

S-scheme heterojunction photocatalyst

Inside Chem.

(2020)

Qiang Liu et al.

Photocatalysis under shell: Co@BN core–shell composites for efficient EY-sensitized photocatalytic hydrogen evolution

Appl. Surf. Sci.

(2020)

Meiyu Zhang et al.

Pyroelectric effect in CdS nanorods decorated with a molecular Co-catalyst for hydrogen evolution

Nano Energy

(2020)

Xiangyu Meng et al.

Carbon quantum dots assisted strategy to synthesize Co@NC for boosting photocatalytic hydrogen evolution performance of CdS

Chem. Eng. J.

(2020)

Wanjun Sun et al.

Amorphous CoO_x coupled carbon dots as a spongy porous bifunctional catalyst for efficient photocatalytic water oxidation and CO₂ reduction

Chin. J. Catal.

(2020)

Yi Lu et al.

Hierarchical CdS/m-TiO₂/G ternary photocatalyst for highly active visible light-induced hydrogen production from water splitting with high stability

Nano Energy

(2018)

Guixia Zhao et al.

Efficient photocatalytic CO₂ reduction over Co(II) species modified CdS in aqueous solution

Appl. Catal. B Environ.

(2018)

Tianxi Zhang et al.

Z-scheme transition metal bridge of Co₉S₈/Cd/CdS tubular heterostructure for enhanced photocatalytic hydrogen evolution

Appl. Catal. B Environ.

(2021)

Xuqiang Hao et al.

Architecture of high efficient zinc vacancy mediated Z-scheme photocatalyst from metal-organic frameworks

Nano Energy

(2018)

Wenlong Zhen et al.

The enhancement of CdS photocatalytic activity for water splitting via anti-photo corrosion by coating Ni₂P shell and removing nascent formed oxygen with artificial gill

Appl. Catal. B Environ.

(2018)

Cited by (12)

Novel noble-metal-free NiCo-LDH/CdSe S-type heterojunction with built-in electric field for high-efficiency photocatalytic H<inf>2</inf> production
2024, Journal of the Taiwan Institute of Chemical Engineers
Constructing heterojunction is one of the effective strategies for boosting carrier separation. Although CdSe is an excellent photocatalytic material, its activity is still very low.
In this paper, NiCo-LDH/CdSe (NCCSe) binary heterojunctions were successfully prepared by a two-step hydrothermal method. The results of photocatalytic tests show that 12NCCSe composites have the highest photocatalytic H₂ production activity, with an average rate of 2929.4 μmol·g⁻¹·h⁻¹, which is 74 times higher than that of pure CdSe (39.5 μmol·g⁻¹·h⁻¹).
There are two main reasons for the obvious improvement of photocatalytic activity. Firstly, the separation efficiency of photogenerated carriers is greatly improved, which is attributed to the formation of S-type heterojunction with built-in electric field. Secondly, the addition of NiCo-LDH greatly enhances the light absorption intensity of NCCSe composites, providing more photogenerated electrons. In addition, the mechanism of increased photocatalytic activity for NCCSe S-type heterojunction composites was further discussed. This work provides a thought for constructing NiCo-LDH-based S-type heterojunction for efficient photocatalytic H₂ production, which could easily extend to other LDHs materials.
Recent progress in CdS-based S-scheme photocatalysts
2024, Journal of Materials Science and Technology
Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further use. Cadmium sulfide (CdS), as a typical reducing semiconductor of metal sulfides, represents an interesting research hotspot in photocatalysis due to its suitable bandgap (2.4 eV) for utilizing visible light and strong reducing ability for inducing surface catalytic reactions. Unfortunately, the photocatalytic performance of CdS is still limited by its fast carrier recombination and serious photocorrosion. So far, CdS semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel S-scheme heterojunction to overcome the above drawbacks. In this review, the design concepts, basic principles, and charge transfer characteristics of CdS-based S-scheme heterojunction photocatalysts have been comprehensively introduced. Several advanced and effective characterization methods for studying the mechanism of CdS-based S-scheme heterojunction are analyzed in detail. Furthermore, we also summarize the typical applications of CdS-based S-scheme heterojunctions for water splitting, CO₂ reduction, pollutant degradation, etc. Eventually, according to the current investigation status, some drawbacks in the current synthetic strategy, mechanism exploration, and application prospect of CdS-based S-scheme heterojunction are proposed, which need to be addressed by further expansion and innovative research.
S-scheme heterojunction in photocatalytic hydrogen production
2024, Journal of Materials Science and Technology
As an ideal secondary energy source, hydrogen has the title of clean energy and the product of its complete combustion is only water, which is not polluting to the environment. Photocatalytic hydrogen production technology is an environmentally friendly, safe, and low-cost strategy that requires only an inexhaustible amount of solar energy and water as feedstock. This paper provides a detailed and detailed review of S-scheme heterojunction photocatalysts for photocatalytic hydrogen production, mainly including TiO₂-based, Perovskite-based, CdS-based, Graphitic phase carbon nitride-based, COF-based graphdiyne-based, ZnO-based, and ZnIn₂S₄-based S-scheme heterojunction photocatalysts. The classification of S-scheme heterojunctions is summarized. What's more, various characterizations for direct verification of the charge migration mechanism of S-scheme heterojunctions are outlined. Based on the present study, the future potential challenges and future research trends for S-scheme heterojunctions in photocatalytic hydrogen evolution technology are pointed out, which provides feasible strategies for the development and design of S-scheme heterojunction photocatalysts in the field of photocatalytic hydrogen evolution.
Core-shell structured Co(OH)F@FeOOH enables highly efficient overall water splitting in alkaline electrolyte
2024, International Journal of Hydrogen Energy
Constructing a low-cost, high activity and stable electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) via overall water splitting is of great significance, but remains a big challenge. In this work, vertically aligned core-shell Co(OH)F@FeOOH nanorod arrays (NRs) on Ni foam were constructed via hydrothermal and chemical deposition methods. Due to the synergistic effects and electron interaction at the interface between Co(OH)F and FeOOH, the synthesized core-shell Co(OH)F@FeOOH heterostructure exhibits remarkable OER and HER catalytic activity in 1 M KOH solution, presenting low overpotentials of approximately 205 mV and 137 mV at a current density of 10 mA cm⁻², and low Tafel slopes of approximately 48 mV dec⁻¹ and 86 mV dec⁻¹, for OER and HER, respectively. Moreover, the synthesized Co(OH)F@FeOOH serves as a bifunctional electrocatalyst for overall water splitting and it only needs 1.55 V to drive the electrolysis cell yielding 10 mA cm⁻² which is much lower than that of 1.68 V for IrO₂||Pt/C and showing excellent stability for 37 h. The prepared Co(OH)F@FeOOH catalyst has been successfully used in solar cell-driven water electrolysis, demonstrating its great potential for cost-effective electrochemical hydrogen production.
Construction of Ag-modified ZnO–CeO<inf>2</inf> 2D-1D S-scheme heterojunction photocatalyst with phenomenal photocatalytic performance for H<inf>2</inf> evolution
2023, Materials Science in Semiconductor Processing
The rational design of S-scheme heterojunctions is a promising strategy to boost the spatial separation of photocarriers and optimize the stability of the heterosystem. Herein, we successfully designed a 2D-1D ZnO–CeO₂–Ag plasmonic heterosystem containing ZnO nanosheets and CeO₂ nanorods through the solvothermal process. The ZnO–CeO₂–Ag exhibits the maximum photocatalytic H₂ evolution rate of 31420 μmol h⁻¹ g⁻¹ under simulated sunlight exposure, which is about 55 and 14 times superior to pure ZnO and CeO₂, respectively. The notably high photocatalytic efficiency of ZnO–CeO₂–Ag is primarily assigned to the design of plasmonic S-scheme heterosystem. This heterosystem promotes visible light absorption due to LSPR phenomenon, which enhances the specific surface area and facilitates the built-in electric field-derived S-scheme separation and transference of photocarriers. The H₂ evolution activity is also examined by varying different parameters, including catalyst dose, initial pH, nature and quantity of sacrificial reagent, and process time. The H₂ evolution rate of ZnO–CeO₂–Ag for consecutive cycles confirmed its high stability and reusability. This research paves the way for the design of possible heterojunction photocatalysts for energy production and environmental remediation.
A review on S-scheme and dual S-scheme heterojunctions for photocatalytic hydrogen evolution, water detoxification and CO<inf>2</inf> reduction
2023, Fuel
Discovering alternative materials and technologies that provide the meaningful potential to environmental and energy-related challenges in critical to the long-term viability of industrial activity and the evolution of society. Photocatalysts are undeniably important, and scientists are working hard to improve their photocatalytic performance. The high recombination rates of photogenerated electron-hole pairs as well as poor redox capability are addressed via heterojunction modification. In this direction, oxidation type and reduction type photocatalysts based S-scheme heterojunctions are highly promising owing to highly diminished recombination facilitated by internal electric field. This review has focused on the shift from Z-scheme to new revolutionary S-scheme based photocatalytic materials with high performance applications in the field of energy and environment. It can be concluded that controllable built-in electric field intensity and stable interfacial carrier transport process make S-scheme heterostrctures ideal. However their application is mainly limited to powder photocatalysts, don’t apply to photo-chemistry and solar cells with external circuit, reaction thermodynamics and dynamics management in S-scheme photocatalysts is not adequate. To some extent, dual S-schemes address to these limitations and further research is to be carried out to fight the bottlenecks. Several perspectives on the future of S-scheme and dual S-scheme heterostructure were also provided based on rigorous review of the reported results.
A discussion on the previously reported different types of heterojunctions and S-schemes is presented in this review along with plausible charge transfer mechanisms. The synthetic routes to S-scheme heterojunctions are also provided along with modifications and combinations. The current designing and perspective applications in numerous pollutant degradation, hydrogen production and CO₂ conversion is selectively highlighted. The transition of mechanism elucidation from Z-scheme to S-scheme has been discussed with suitable case studies. However, S-scheme heterojunctions designing and fabrication is still new commercially and so present readiness and bottlenecks have been discussed. Hence it is quite imperative for a future roadmap to be laid to design and develop economically viable high performance S-scheme heterojunctions.

View all citing articles on Scopus

View full text

Hexagonal CdS assembled with lamellar NiCo LDH form S-scheme heterojunction for photocatalytic hydrogen evolution

Highlights

Abstract

Graphical abstract

Introduction

Section snippets

The synthesis method of NiCo LDH

Preparation of CdS

XRD analysis

Conclusion

Author contributions

Declaration of competing interest

Acknowledgements

Appl. Catal. B Environ.

Appl. Catal. B Environ.

Chem. Eng. J.

Appl. Catal. B Environ.

Appl. Catal. B Environ.

Nano Energy

Chem. Eng. J.

Appl. Catal. B Environ.

Joule

Appl. Catal. B Environ.

Appl. Catal. B Environ.

Inside Chem.

Appl. Surf. Sci.

Nano Energy

Chem. Eng. J.

Chin. J. Catal.

Nano Energy

Appl. Catal. B Environ.

Appl. Catal. B Environ.

Nano Energy

Appl. Catal. B Environ.