熔盐法制备K+-g-C3N4及其光催化降解有机污染物性能

Abstract
Figure/Table
References
Related Citation (15)

Download: PDF (921 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract A band gap-tunable potassium doped graphitic carbon nitride (g-C₃N₄) with enhanced RhB degradation ability was prepared via molten salt method. X-ray diffraction (XRD), UV-Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), N₂ adsorption, Photoluminescence (PL) and Electrochemical impedance spectra (EIS) were used to characterize the prepared catalysts. The addition of potassium inhibited the crystal growth of graphitic carbon nitride, enhanced the surface area and increased the separation rate of photogenerated electrons and holes. In addition, by controlling the potassium ion doping amount, the CB and VB potentials of graphitic carbon nitride can be adjusted within a certain range, so that the oxidative degradation reaction of organic pollutants changes from single oxidant (·O₂^-) reaction to double oxidant (·OH and·O₂^-) reaction, leading to the promoted degradation and mineralization ability. The RhB degradation rate constant of as-prepared potassium ion doped catalyst arrived 0.022min^-1, which is 5 times higher than that of neat g-C₃N₄. Moreover, the degradation rate of the as-prepared catalyst to other organic pollutants, such as methyl blue and phenol, was also significantly improved by tuning the energy level.

Key words： g-C₃N₄ K⁺ doping molten salt method energy level control photocatalysis

Received: 11 December 2019

PACS:

X131

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	HU Shao-zheng
	LI Wei
	GU Gui-zhou
	YUAN Xing-zhou
	LIANG Fei-xue
	WU Guang

Cite this article:

HU Shao-zheng,LI Wei,GU Gui-zhou等. Preparation of potassium ion doped graphite carbon nitride via molten salt method and its photocatalytic mineralization ability of organic pollutants[J]. CHINA ENVIRONMENTAL SCIENCECE, 2020, 40(7): 3106-3113.

URL:

http://www.zghjkx.com.cn/EN/ OR http://www.zghjkx.com.cn/EN/Y2020/V40/I7/3106

[1]	Zhang J, Zhang G, Chen X, et al. Co-monomer control of carbon nitride semiconductors to optimize hydrogen evolution with visible light[J]. Angewandte Chemie, 2012,51:3183-3187.
[2]	Bu Y, Chen Z, Li W. Using electrochemical methods to study the promotion mechanism of the photoelectric conversion performance of Ag-modified mesoporous g-C3N4heterojunction material[J]. Applied Catalysis B:Environmental, 2014,144:622-630.
[3]	Xu J, Wu H, Wang X, et al. A new and environmentally benign precursor for the synthesis of mesoporous g-C3N4 with tunable surface area[J]. Physical Chemistry Chemical Physics, 2013,15:4510-4517.
[4]	Chang C, Fu Y, Hu M, et al. Photodegradation of bisphenol a by highly stable palladium-doped mesoporous graphite carbon nitride (Pd/mpg-C3N4) under simulated solar light irradiation[J]. Applied Catalysis B:Environmental, 2013,142-143:553-560.
[5]	Liu J, Yu Y, Qi R, et al. Enhanced electron separation on in-plane benzene-ring doped g-C3N4 nanosheets for visible light photocatalytic hydrogen evolution[J]. Applied Catalysis B:Environmental, 2019,244:459-464.
[6]	Dong G, Ho W, Wang C. Selective photocatalytic N2 fixation dependent on g-C3N4 induced by nitrogen vacancies[J]. Journal of Materials Chemistry A, 2015,3:23435-23441.
[7]	Hu S, Li Y, Li F, et al. Construction of g-C3N4/Zn0.11Sn0.12Cd0.88S1.12 hybrid heterojunction catalyst with outstanding nitrogen photofixation performance induced by sulfur vacancies[J]. ACS Sustainable Chemistry Engineering, 2016,4:2269-2278.
[8]	Zhang Y, Mori T, Ye J, et al. Phosphorus-doped carbon nitride solid:enhanced electrical conductivity and photocurrent generation[J]. Journal of the American Chemical Society, 2010,132:6294-6295.
[9]	Di J, Xia J, Yin S, et al. Preparation of sphere-like g-C3N4/BiOI photocatalysts via a reactable ionic liquid for visible-light-driven photocatalytic degradation of pollutants[J]. Journal of Materials Chemistry A, 2014,2:5340-5351.
[10]	Tian N, Huang H, Liu C, et al. In situ co-pyrolysis fabrication of CeO2/g-C3N4n-n type heterojunction for synchronously promoting photo-induced oxidation and reduction properties[J]. Journal of Materials Chemistry A, 2015,3:17120-17129.
[11]	Hu S, Ma L, You J, et al. Enhanced visible light photocatalytic performance of g-C3N4photocatalysts co-doped with iron and phosphorus[J]. Applied Surface Science, 2014,311:164-171.
[12]	Wang X, Maeda K, Thomas A, et al. A metal-free polymeric photocatalyst for hydrogen production from water under visible light[J]. Nature Materials, 2009,8:76-80.
[13]	Liu G, Niu P, Yin L, et al. α-Sulfur crystals as a visible-light-active photocatalyst[J]. Journal of the American Chemical Society, 2012, 134:9070-9073.
[14]	Volkov S. Chemical reactions in molten salts and their classification[J]. Chemical Society Reviews, 1990,19:21-28.
[15]	Kerridge D. Recent advances in molten salts as reaction media[J]. Pure and Applied Chemistry, 1975,41:355-371.
[16]	Sudworth J. The sodium/nickel chloride (ZEBRA) battery[J]. Journal of Power Sources, 2001,100:149-163.
[17]	Chen G, Fray D Farthing T. Direct electrochemical reduction of titanium dioxide to titanium in molten calcium chloride[J]. Nature, 2000,407:361-364.
[18]	Nohira T, Yasuda K, Ito Y. Pinpoint and bulk electrochemical reduction of insulating silicon dioxide to silicon[J]. Nature Materials, 2003,2:397-401.
[19]	Bojdys M, Muller J, Antonietti M, et al. Ionothermal synthesis of crystalline, condensed, graphitic carbon nitride[J]. Chemistry-A European Journal, 2008,14:8177-8182.
[20]	Wang Y, Wang X, Antonietti M. Polymeric graphitic carbon nitride as a heterogeneous organocatalyst:from photochemistry to multipurpose catalysis to sustainable chemistry[J]. Angewandte Chemie (International ed. in English), 2012,51:68-89.
[21]	Liu L, Ma D, Zheng H, et al. Synthesis and characterization of microporous carbon nitride[J]. Microporous and Mesoporous Materials, 2008,110:216-222.
[22]	Li G, Yang N, Wang W, et al. Synthesis, photophysical and photocatalytic properties of N-doped sodium niobate sensitized by carbon nitride[J]. The Journal Physical Chemistry C, 2009,113:14829-14833.
[23]	Lei W, Portehault D, Dimova R, et al. Boron carbon nitride nanostructures from salt melts:tunable water-soluble phosphors[J]. Journal of the American Chemical Society, 2011,133:7121-7127.
[24]	Ma X, Lv Y, Xu J, et al. A strategy of enhancing the photoactivity of g-C3N4via doping of nonmetal elements:a first-principles study[J]. The Journal Physical Chemistry C, 2012,116:23485-23493.
[25]	Xiong T, Cen W, Zhang Y, et al. Bridging the g-C3N4interlayers for enhanced photocatalysis[J]. ACS Catalysis, 2016,6:2462-2472.
[26]	Deifallah M, McMillan P, Corà F. Electronic and structural properties of two-dimensional carbon nitride graphenes[J]. The Journal Physical Chemistry C, 2008,112:5447-5453.
[27]	Xu Y, Xu H, Wang L, et al. The CNT modified white C3N4composite photocatalyst with enhanced visible-light response photoactivity[J]. Dalton Transaction, 2013,42:7604-7613.
[28]	Qu X, Hu S, Bai J, et al. Synthesis of band gap-tunable alkali metal modified graphitic carbon nitride with outstanding photocatalytic H2O2production ability via molten salt method[J]. Journal of Materials Science & Technology, 2018,34:1932-1938.
[29]	Zhang S, Yang Y, Guo Y, et al. Preparation and enhanced visible-light photocatalytic activity of graphitic carbon nitride/bismuth niobate heterojunctions[J]. Journal of Hazardous Materials, 2013,261:235-245.