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Unsatisfied visible light response and high recombination probability of photogenerated charge carriers greatly limit the advanced application of graphitic carbon nitride (CN). Here, the novel Cu and C co-doping CN (Cu/C-CN) photocatalyst is successfully fabricated by thermal polymerization of the melamine and chlorophyll sodium copper salt as precursors, which significantly improves the photocatalytic performance than pure CN. A series of characterizations confirm that the co-doped Cu and C in CN not only endow the material with improved light harvest abilities and narrowed band gap, but also facilitate the charge carriers separation. As a result, the Cu/C-CN-0.3 photocatalyst exhibits a highly efficient photocatalytic degradation of RhB, the reaction rate constant of Cu/C-CN-0.3 (kapp=0.036 min−1) is almost 13 times higher than CN (kapp = 0.0027 min−1). This study may open a new perspective for constructing other dual-elements co-doped CN materials with high performance and application in wastewater treatment. [ABSTRACT FROM AUTHOR]

A smart bioreactor (HPs-Ag), designed by protein-silver nanoclusters-PNIPAAm, could control the membrane permeability to determine the different molecular weight of materials and the speed of catalysis of enzyme reaction. Studies also showed that the molecular weight cutoff of the HPs-Ag membrane could be continuously turned up from 12 to 70 kDa. The catalytic reaction rate of the ALP loaded bared HPs-Ag by using pNPP as substrates was increased (18.14- and 9.23-fold) with different concentrations of H2O2. [ABSTRACT FROM AUTHOR]

A series of colloidal Ag3PO4 sphere loaded onto multi-walled carbon nanotube (CAPS-MWCNT) photocatalysts containing different mass ratio of MWCNT for the removal of RhB and phenol from waste water were synthesized. The photocatalysts were characterized by X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, thermogravimetry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy. By SEM and TEM test, the obtained Ag3PO4 form precipitated and colloidal method present different structure morphology and this showed an important effect on the photocatalytic activity. The CAPS-MWCNT photocatalysts were applied to the removal of Rhodamine B (RhB) and phenol from waste water; and the results indicated that CAPS-MWCNT sample can exhibit the high adsorption and photodegradation efficiency under visible light irradiation. For RhB, the removal efficiency of CAPS-MWCNT-4 reaches 99.8% within 50 min, of which adsorption efficiency is 76.5% within the former 30 min; for phenol, the removal efficiency of CAPS-MWCNT-4 reaches 90.6% within 110 min, of which adsorption efficiency is 14.2% within the former 30 min. The experiment results show that CAPS-MWCNT-4 has the highest removal efficiency for RhB while it presents an excellent reusability for removing phenol from waste water. The present work illustrates a new train for the design and synthesis of stable and high efficiency catalysts, applicable for the removal of various organic pollutants by adsorption and photodegradation. [ABSTRACT FROM AUTHOR]

A unique polymeric carbon nitride (CN) tubular sponge with an edge-functionalized phosphonic group (CNPC) has been obtained using a simple template-free method. Using phenylphosphonic acid as an additive promotes the formation of a cyanuric acid–melamine supramolecular precursor. Meanwhile, phosphonic groups are grafted to heptazine units. Experimental and characterization investigations reveal that the functional phosphonic group and tubular sponge morphology endow CNPCx with additional reaction active sites, negative conduction band levels, and highly efficient charge separation. The obtained CNPCx photocatalysts exhibit excellent catalytic performance with regard to H2 evolution and contaminant degradation. This study provides a new design based on the synergetic regulating effect of macro and microstructures of CN with high performance in energy conversion and environmental purification. [ABSTRACT FROM AUTHOR]