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The Ni-rich Li(Ni 0.8 Co 0.1 Mn 0.1)O 2 (NCM 811) is surface-modified using phosphoric acid (HPO) and silane reagents, and water-based cathode slurries of unmodified and modified NCM 811 are prepared with poly(acrylonitrile) (PAN) or poly(acrylic acid) (PAA) added as the binder to compare the electrochemical performances of the constructed cells. Surface modification using HPO or the addition of PAA as the binder can substantially reduce the alkalinity of the prepared aqueous slurry of NCM 811 , thereby preventing the slurry from corroding the aluminum current collector, as well as retaining the good structural integrity of the dried electrode. The aforementioned advantage about the reduction in the alkalinity is not achieved when the hydrophobic silane-modified NCM 811 or the neutral binder PAN is used. The best cell performance in terms of electrochemical reversibility, ionic and electronic impedance, and cycle stability is obtained when the water-based cathode slurry is prepared using HPO-modified NCM 811 as the cathode active and PAA as the binder simultaneously. Moreover, the addition of PAA rather than the adoption of HPO-modified NCM 811 contributes more to the improvement of cell performance. Image 1 • Poly(acrylic acid) is an ideal binder for water-processed Li(Ni 0.8 Co 0.1 Mn 0.1)O 2 cathode. • Phosphoric acid modification improves the electrochemistry of Li(Ni 0.8 Co 0.1 Mn 0.1)O 2. • Good cell performance of water-processed Li(Ni 0.8 Co 0.1 Mn 0.1)O 2 cathode is obtained. [ABSTRACT FROM AUTHOR]

Abstract A new photocatalyst is proposed that incorporates TiO 2 nanopowder into a three-dimensional carbon skeleton to create a TiO 2 /C porous microsphere with adjustable pore size, and its photocatalytic activity is investigated and compared to that of a commercially available photocatalytic powder (P25). The photocatalytic efficiency of the proposed TiO 2 /C porous microsphere achieves a considerable improvement of more than 2–3 times that of P25 when irradiated by UV and visible lights. With the further incorporation of Fe, the TiO 2 /C/Fe porous microsphere exhibits maximum photodegradation efficiencies of 97% and 45% when low-power UV and visible lights are the energy sources, respectively; these are significantly higher than the 40% and 10% measured for P25. In addition, the major mechanism for this improvement in photocatalytic activity by the porous microsphere is identified by calculating band gap energies based on a modified Kubelka-Munk function. Graphical abstract Image 1 Highlights • A new porous structure of nano-TiO 2 -based photocatalyst is constructed. • The proposed new photocatalyst is magnetic and recyclable for repeated use. • The porous photocatalyst provides efficiency of 97% under low-power UV irradiation. • A more than 3 times of improvement in photocatalysis under visible-light is achieved. [ABSTRACT FROM AUTHOR]