Preparation of K⁺ doped ZnO nanorods with enhanced photocatalytic performance under visible light

Abstract

Due to their ease of preparation, low cost and environmentally-friendly characteristics, zinc-type photocatalysts have attracted a lot of interest with regards to the photocatalytic degradation of organic pollutants. In this study, K+ doped ZnO (KZO) microcrystals were prepared from zinc acetate dehydrate and potassium hydroxide. X-ray diffraction analysis revealed the structure of the hexagonal wurtzite and the substitution of potassium ions in zinc oxide. A scanning electron microscope image showed the nanorod microstructure of prepared KZO crystallites. UV–visible analysis showed that the light absorption of KZO crystals expanded to the visible region and possessed a narrower band gap. In addition, the photocatalytic performance of KZO nanoparticles was evaluated. The results show that KZO possesses enhanced activity which is 3.45 times that of pure ZnO. This high performance in the photocatalytic degradation of organic pollutants can be ascribed to the band gap reduction, large surface area and improved transmission of charge carriers.

K+-Doped ZnO/g-C3N4 Heterojunction: Controllable Preparation, Efficient Charge Separation, and Excellent Photocatalytic VOC Degradation Performance

“…The splitting among the two binding energy peaks was 23.0 eV, demonstrating that the Zn was present as Zn 2+ in the KZOCN-3 . It could be seen from Figure c that the peak of K 2p corresponded to 290.8 eV proved that K existed in KZOCN-3 in the form of K + . As shown in Figure d, the C 1s region was divided into three peaks.…”

“…The volatile organic compounds (VOCs) emitted from industrial production had seriously affected the air quality of the earth, and the VOC purification technology had attracted more and more attention. , As a green, clean, and environment-friendly technology, photocatalysis could degrade and mineralize VOCs directly, which exhibited a wide application expectation in air purification. − Recent years, metal oxide semiconductors showed good photocatalytic performance, which had attracted extensive attention. In various metal oxide semiconductors, ZnO was considered as a good photocatalyst material because of excellent photocatalytic performance, suitable electronic band structure, nontoxicity, and low cost. − However, the low electron–hole separation efficiency, severe photocorrosion, and poor light absorption capacity limited its full commercial applications. , It had been reported that the doping of nonmetal element or metal element in ZnO could reduce its band gap, expand optical response range, and improve its photocatalytic performance. ,− Recently, K + -doped ZnO photocatalysts were studied in our group, the obtained K + -doped ZnO exhibited narrower band gap width and better photocatalytic performance than single-component ZnO . However, the serious charge recombination of K + -doped ZnO still limited its applications in the photocatalytic field.…”

“…12,14−18 Recently, K + -doped ZnO photocatalysts were studied in our group, the obtained K + -doped ZnO exhibited narrower band gap width and better photocatalytic performance than single-component ZnO. 19 However, the serious charge recombination of K + -doped ZnO still limited its applications in the photocatalytic field.…”

MIL-100(Fe)/g-C3N4 composites with enhanced photocatalytic activity for UO22+ reduction under visible light

“…However, different samples presented different photocurrent densities. MIL/CN 0.1 exhibited higher photocurrent density under illumination compared to CN, indicated stronger photo-generated carrier separation and transfer efficiency [26], and the improved light trapping ability could effectively promote the efficiency of photocatalytic reduction of UO 2 2+ .…”

Material Design and Surface/Interface Engineering of Photoelectrodes for Solar Water Splitting

“…In most intrinsic semiconductors, the carrier concentration is low, and the conductivity of semiconductors is poor. [ 57 ] The introduction of donor‐type impurities into semiconductors can increase the electron concentration, thereby enhancing the conductivity of the semiconductors. [ 58 ] For example, the carrier concentration of intrinsic Si is ≈1.5 × 10 10 cm −3 at room temperature.…”