Photocatalytic technology is an attractive option for environmental remediation because of its green and sustainable nature. However, the inefficient utilization of solar energy and powder morphology currently impede its practical application. Here, we designed a floatable photocatalyst by anchoring 0D Cu2(OH)PO4 (CHP) nanoparticles on 2D graphene to construct 0D/2D CHP/reduced graphene oxide (rGO) aerogels. The CHP/rGO aerogels have interconnected mesopores that provide a large surface area, promoting particle dispersion and increasing the number of active sites. Moreover, the optical response of the CHP/rGO aerogel has been significantly expanded to cover the full spectrum of the solar light. Notably, the 20%CHP/rGO aerogel displayed a high degradation rate (k = 0.178 min–1) taking methylene blue (MB) as a model pollutant under light irradiation (λ > 420 nm). The enhanced photocatalytic activity is ascribed to the rapid electron transfer in the CHP/rGO heterostructures, as supported by the DFT theoretical calculations. Our research highlights the utilization of full spectrum responsive photocatalysts for the elimination of organic pollutants from wastewater under solar light irradiation, as well as the potential for catalyst recovery using floatable aerogels to meet industrial requirements.
Wei Guo,Zhenyu Qiu,Chongshen Guo,Dandan Ding,Tianchan Li,Fei Wang,Jianzhe Sun,Nannan Zheng,Shaoqin Liu
Image-guided phototherapy is considered to be a prospective technique for cancer treatment because it can provide both oncotherapy and bioimaging, thus achieving an optimized therapeutic efficacy and higher treatment accuracy. Compared to complicated systems with multiple components, using a single material for this multifunctional purpose is preferable. In this work, we strategically fabricated poly(acrylic acid)- (PAA-) coated Cu2(OH)PO4 quantum dots [denoted as Cu2(OH)PO4@PAA QDs], which exhibit a strong near-infrared photoabsorption ability. As a result, an excellent photothermal conversion ability and the photoactivated formation of reactive oxygen species could be realized upon NIR irradiation, concurrently meeting the basic requirements for photothermal and photodynamic therapies. Moreover, phototherapeutic investigations on both cervical cancer cells in vitro and solid tumors of an in vivo mice model illustrated the effective antitumor effects of Cu2(OH)PO4@PAA upon 1064-nm laser irradiation, with no detectable lesions in major organs during treatment. Meanwhile, Cu2(OH)PO4@PAA is also an exogenous contrast for photoacoustic tomography (PAT) imaging to depict tumors under NIR irradiation. In brief, the Cu2(OH)PO4@PAA QDs prepared in this work are expected to serve as a multifunctional theranostic platform.
Sparked by the growing environmental crises, photocatalytic degradation of chlorophenols with inexhaustible solar energy is expected to be converted into actual applications. Here, we report the preparation of the nanocomposite of Cu2(OH)PO4 and reduced graphene oxide (Cu2(OH)PO4/rGO) through a one-step hydrothermal method and examined its infrared-light photocatalytic activity in the degradation of 2,4-dichlorophenol (2,4-DCP). As evidenced by the absorption spectra and the degradation of 2,4-DCP, Cu2(OH)PO4/rGO exhibited enhanced infrared light-driven photocatalytic activity compared to pure Cu2(OH)PO4 and was very stable even after repeated cycling. More importantly, the introduction of hydrogen peroxide (H2O2) could combine the photocatalytic and photo-Fenton effects into one reaction system and maximize the infrared light photocatalytic efficiency. Typically, the rate constant of Cu2(OH)PO4/rGO and H2O2 was more than 6.25 times higher than that of only Cu2(OH)PO4/rGO, and almost 10 times greater than the value for pure Cu2(OH)PO4. Further, a plausible mechanism for the enhanced photocatalytic properties of Cu2(OH)PO4/rGO has been discussed. These findings may help the development of novel hybrid photocatalysts with enhanced infrared light photocatalytic activity for applications in the treatment of chlorophenol-contaminated wastewater.