Preparation and characterization of wheat straw biochar loaded with aluminium/lanthanum hydroxides: a novel adsorbent for removing fluoride from drinking water.

In this work, a novel adsorbent of aluminium/lanthanum loaded wheat straw biochar (Al-La-WSB), was prepared by using a facile approach and used for fluoride removal. The Al-La-WSB and its pristine wheat straw biochar (WSB) were characterized by scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray powder diffraction (XRD) methods. Batch adsorption experiments were carried out to investigate adsorbent performance, the highest removal rate was observed at pH 9, contact time of 7 h and Al-La-WSB dose of 1 g L-1. Lagergren pseudo-second-order kinetics and Langmuir isotherm model fitted the experimental data well. The maximum fluoride adsorption capacity of Al-La-WSB at different experiment temperature of 298, 308 and 318 K, was 51.28 mg g-1, 46.73 mg g-1 and 50.25 mg g-1, respectively, which was better than most reported adsorbents. The Al-La-WSB performed well over a considerable wide pH range of 3-10 and carried positive charge at pH < 4.8. The presence co-existing ions of SO42-, HCO3-, Cl- and NO3- had a minor impact on fluoride adsorption besides PO43-. Regeneration experiment results showed that the Al-La-WSB had an excellent reusability. According to the adsorbent characterization and batch adsorption experiment, the adsorption of fluoride on the Al-La-WSB was primarily a chemisorption, involving electrostatic interactions and ion exchange, which nitrate ion and hydroxyl played a major role. The results suggested that the Al-La-WSB could be a great adsorbent for removing fluoride from drinking water.

Boron-modulated surface of hollow nickel framework for improved hydrogen evolution.

A hollow Ni framework (HNF) is designed and prepared to utilize the exterior and interior surface active sites of a Ni-based binder-free and support-free electrode. Furthermore, the more efficient Ni-B active sites are then in situ introduced on the surface of HNF. This micro/nano structure engineering, together with the surface boron modulation, results in a synergistically enhanced catalytic effect for the HER performance.

Self-derivation-behaviour of substrates realizing enhanced oxygen evolution reaction.

Self-derivation-behaviour of substrates is utilized to fabricate monolithic electrodes for oxygen evolution, in which the selected substrate functions as both the precursor of the active catalyst and a conductive support. In particular, NiFe layered double hydroxide (LDH) can be directly derived from the surface metal of commercial NiFe foam (NFF). Moreover, the as-prepared monolithic electrode exhibits enhanced activity and durability, originating from the resultant defective nanosheet structure and autologous catalyst-support features.