Chen Huajun

Bio: Chen Huajun is an academic researcher from Luoyang Institute of Science and Technology. The author has contributed to research in topics: Graphene & Nanosheet. The author has an hindex of 6, co-authored 35 publications receiving 189 citations. Previous affiliations of Chen Huajun include Shaanxi University of Science and Technology.

Flexible Carbon-Fiber/Semimetal Bi Nanosheet Arrays as Separable and Recyclable Plasmonic Photocatalysts and Photoelectrocatalysts

Abstract: In this work, we prepared flexible carbon-fiber/semimetal Bi nanosheet arrays from solvothermal-synthesized carbon-fiber/Bi2O2CO3 nanosheet arrays via a reductive calcination process. The flexible carbon-fiber/semimetal Bi nanosheet arrays can function as photocatalysts and photoelectrocatalysts for 2,4-dinitorphenol oxidation. Compared with carbon-fiber/Bi2O2CO3 nanosheet arrays, the newly designed flexible carbon-fiber/semimetal Bi nanosheet arrays show enhanced ultraviolet-visible (UV-vis) light absorption efficiency and photocurrent, photocatalytic, and photoelectrocatalytic activities. Photocatalytic analyses indicate that the surface plasmon resonance (SPR) of semimetal Bi occurs under solar-simulated light irradiation during the photocatalytic process. The carbon-fiber traps the hot electrons exerted from the SPR of semimetal Bi and creates holes in the semimetal Bi nanosheets, which boosts the photocatalytic activity of the carbon fiber through plasmonic sensitization. Both photocatalytic experiments and density functional theory (DFT) calculations indicate that the electrons transferred to the carbon fiber and the holes created in semimetal Bi contribute to the formation of •O2- and •OH, respectively. The synergistic effect between electrocatalysis and photocatalysis under the solar-simulated light results in almost complete degradation of 2,4-dinitorphenol during the photoelectrocatalytic process. This work realizes a non-noble-metal plasmonic catalyst and provides a new avenue for the commercialization of photocatalysis and photoelectrocatalysis using the separable and recyclable carbon-fiber/semimetal Bi nanosheet arrays in the environment-related field.

Self-Standing Film Assembled using SnS-Sn/Multiwalled Carbon Nanotubes Encapsulated Carbon Fibers: A Potential Large-Scale Production Material for Ultra-stable Sodium-Ion Battery Anodes.

Abstract: High-energy sodium-ion batteries have a significant prospective application as a next-generation energy storage technology. However, this technology is severely hindered by the lack of large-scale production of battery materials. Herein, a self-standing film, assembled with SnS-Sn/multiwalled carbon nanotubes encapsulated in carbon fibers (SnS-Sn/MCNTs@CFs), is prepared using ball milling and electrospinning techniques and used as sodium-ion battery anodes. To compensate the poor internal conductivity of SnS-Sn nanoparticles, MCNTs are used to interweave SnS-Sn nanoparticles to improve the conductivity. Moreover, the designed three-dimensional carbon fiber conductive network can effectively shorten the diffusion path of electron/Na+, accelerate the reaction kinetics, and provide abundant active sites for sodium absorption. Benefiting from these unique features, the self-standing film offers a high reversible capacity of 568 mA h g-1 at 0.1 A g-1 and excellent cycling stability at 1 A g-1 with a reversible capacity of 359.3 mA h g-1 after 1000 cycles. In the sodium-ion full cell device, the capacity is stable at 283.7 mA h g-1 after 100 cycles at a current of 100 mA g-1. This work provides a new strategy for electrode design and facilitates the large-scale application of the sodium-ion battery.

Hierarchical SnS2/carbon nanotube@reduced graphene oxide composite as an anode for ultra-stable sodium-ion batteries

Abstract: Ultrathin SnS2 layers with high theoretical specific capacity displays promising advantages as an anode in sodium storage systems. However, their poor conductivity and large capacity loss during charging/discharging process are urgently needed to be addressed. Herein, an exotic hierarchical SnS2/carbon nanotube@reduced graphene oxide (SnS2/CNT@rGO) composite has been designed and developed to be an anode for sodium-ion batteries. Functionally, the CNT penetrates into the petals of SnS2 micro-flowers to increase the conductivity of SnS2, while the three-dimensional rGO wraps around the SnS2/CNT composite to relieve the volume expansion of SnS2 during the charging/discharging process and construct “rGO conductive bridge” to accelerate electrode reaction kinetics. Benefiting from these exotic functionalization, the SnS2/CNT@rGO anode possesses excellent reversible capacity and superior cycling stability with a high reversible capacity of 528 mA h g−1 at 50 mA g−1 and a retained capacity of 301 mA h g−1 after 1000 cycles at 1 A g−1, which are better than most of the previously reported Sn-based and carbon-based anode materials. This study offers a promising strategy for significantly improving the cycling stability in the ultra-stable electrode materials in sodium-ion batteries.

Flexible Carbon-Fiber/Semimetal Bi Nanosheet Arrays as Separable and Recyclable Plasmonic Photocatalysts and Photoelectrocatalysts

Abstract: In this work, we prepared flexible carbon-fiber/semimetal Bi nanosheet arrays from solvothermal-synthesized carbon-fiber/Bi2O2CO3 nanosheet arrays via a reductive calcination process. The flexible carbon-fiber/semimetal Bi nanosheet arrays can function as photocatalysts and photoelectrocatalysts for 2,4-dinitorphenol oxidation. Compared with carbon-fiber/Bi2O2CO3 nanosheet arrays, the newly designed flexible carbon-fiber/semimetal Bi nanosheet arrays show enhanced ultraviolet-visible (UV-vis) light absorption efficiency and photocurrent, photocatalytic, and photoelectrocatalytic activities. Photocatalytic analyses indicate that the surface plasmon resonance (SPR) of semimetal Bi occurs under solar-simulated light irradiation during the photocatalytic process. The carbon-fiber traps the hot electrons exerted from the SPR of semimetal Bi and creates holes in the semimetal Bi nanosheets, which boosts the photocatalytic activity of the carbon fiber through plasmonic sensitization. Both photocatalytic experiments and density functional theory (DFT) calculations indicate that the electrons transferred to the carbon fiber and the holes created in semimetal Bi contribute to the formation of •O2- and •OH, respectively. The synergistic effect between electrocatalysis and photocatalysis under the solar-simulated light results in almost complete degradation of 2,4-dinitorphenol during the photoelectrocatalytic process. This work realizes a non-noble-metal plasmonic catalyst and provides a new avenue for the commercialization of photocatalysis and photoelectrocatalysis using the separable and recyclable carbon-fiber/semimetal Bi nanosheet arrays in the environment-related field.

Hollow semiconductor photocatalysts for solar energy conversion

Abstract: The development of high-efficient photocatalysts plays an important role in the sustainable utilization of solar energy. Hollow nanostructured photocatalysts are vital for solar light utilization and charge carrier separation in photocatalytic processes. Therefore, the construction of hollow semiconductor photocatalysts is a promising strategy for preparing novel high-efficient photocatalysts. This paper reviews common hollow semiconductor nanomaterials, such as oxides, sulfides, nitrides, C3N4, MOFs, and their composite photocatalysts. The characteristics of hollow-structure photocatalysts, the application of solar energy conversion, and their understanding of the photocatalytic mechanism are also reviewed. In addition, future challenges will be focused on designing and majorizing broadband response hollow-structure photocatalysts to further enhance solar energy conversion. Hollow semiconductor photocatalysts will have potential applications in the natural environment, and these synthesized strategies can also provide new possibilities for synthesizing other high-performance semiconductor photocatalysts.

Mainstream Optimization Strategies for Cathode Materials of Sodium‐Ion Batteries

Abstract: Sodium‐ion batteries are promising candidates for grid‐scale energy storage due to its abundance and similarities to lithium‐ion batteries, whereas the lack of ideal cathode materials limits their practical development. Apart from exploring novel materials, applying optimization strategies on existing potential cathode materials is demonstrated to be effective and efficient in improving their electrochemical properties toward their theoretical best capabilities. Reported strategies include element doping, surface coating, morphology and structure design, defect engineering, etc. Herein, focusing on oxide and polyanionic cathode materials, a comprehensive and systematic review on emerging optimization strategies is provided by discussing representative studies of each. Corresponding fundamental principles, their applicable ranges, and common influences on properties are analyzed. Finally, the perspectives on the current impediments and future directions in the field are presented.