In this work, a one-pot solution method for direct synthesis of interconnected ultrafine amorphous NiFe-layered double hydroxide (NiFe-LDH) (<5 nm) and nanocarbon using the molecular precursor of metal and carbon sources is presented for the first time. During the solvothermal synthesis of NiFe-LDH, the organic ligand decomposes and transforms to amorphous carbon with graphitic nanodomains by catalytic effect of Fe. The confined growth of both NiFe-LDH and carbon in one single sheet results in fully integrated amorphous NiFe-LDH/C nanohybrid, allowing the harness of the high intrinsic activity of NiFe-LDH due to (i) amorphous and distorted LDH structure, (ii) enhanced active surface area, and (iii) strong coupling between the active phase and carbon. As such, the resultant NiFe-LDH/C exhibits superior activity and stability. Different from postdeposition or electrostatic self-assembly process for the formation of LDH/C composite, this method offers one new opportunity to fabricate high-performance oxygen evolution reaction and possibly other catalysts.

Copper silicate has so far been the only transition metal silicate that can be synthesized into a single-walled nanotubular structure. In addition to making single-walled copper silicate nanotubes (CuSiNT) as hollow spherical or bundle-like assemblages, herein, we developed a general method to synthesize a series of new single-walled silicate nanotubes containing other 3d transition metal elements (M = Mn, Fe, Co, Ni, and Zn). After the controllable synthesis of CuSiNT, up to 80% of Cu in the CuSiNT can be replaced with dopant metals (M) through complex-assisted ion exchange, while the original tubular structure remains intact. These metal silicate nanotubes can serve as solid precursors for design-made nanocatalysts; enhanced catalytic performance has been demonstrated using CO2 hydrogenation as a model reaction.

Flame-made TiO2 nanoparticles with tunable polymorphs, including the metastable TiO2-II phase, were prepared and a phase formation mechanism was proposed.

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