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We report new metal-free chiral electrodes for catalyzing the asymmetric reduction of aromatic ketones. Multi-walled carbon nanotubes (MWCNTs) were functionalized by chiral amino acids. The resulting amino acid-functionalized MWCNTs were fully characterized by surface analysis and spectroscopic tools and were used as a cathode for the electroreduction of 2,2,2-trifluoroacetophenone in MeCN/n-amyl alcohol (1:1)-TEAI (0.1 M). Electroreduction at l -arginine-MWCNTs and d -arginine-MWCNTs cathodes afforded, respectively, (R)- and (S)-α-(trifluoromethyl) benzyl alcohol in 60–61% yield with 43–44% enantiomeric excess (ee). The l -lysine-MWCNTs cathode gave a lower ee value of the R enantiomer (30%). The yields and ee values were a little bit lower for the electroreduction of acetophenone and other arylalkyl ketones. These amino acid-functionalized MWCNTs electrodes, in addition to showing good catalytic performance, are very stable and can be reused without loss of activity and selectivity.

Non-noble metal oxides consisting of CuO and TiO2 (CuO/TiO2 catalyst) for CO2 reduction were fabricated using a simple hydrothermal method. The designed catalysts of CuO could be in situ reduced to a metallic Cu-forming Cu/TiO2 catalyst, which could efficiently catalyze CO2 reduction to multi-carbon oxygenates (ethanol, acetone, and n-propanol) with a maximum overall faradaic efficiency of 47.4% at a potential of −0.85 V vs. reversible hydrogen electrode (RHE) in 0.5 M KHCO3 solution. The catalytic activity for CO2 electroreduction strongly depends on the CuO contents of the catalysts as-prepared, resulting in different electrochemistry surface areas. The significantly improved CO2 catalytic activity of CuO/TiO2 might be due to the strong CO2 adsorption ability.

An Ag-ZSM-5/SS zeolite modified electrode has been prepared by a facile one-step method, during which Ag nanoparticles were formed in situ with a ZSM-5 film grown on a stainless steel substrate. The morphology and composition were characterized by XRD, SEM, TEM, EDX, H2-TPR, XPS, etc. Ag-ZSM-5/SS possessed much higher catalytic activity towards the electroreduction and electrocarboxylation of PhCH2Cl compared with an Ag bulk electrode.

A simple one-pot synthesis of Ni nanoparticle/ordered mesoporous carbon composite electrode materials is demonstrated for electrosynthesis for the first time. The obtained nanocomposites have uniform mesopore sizes (3.0-3.7 nm), large specific surface areas (506-633 m2 g-1), high pore volumes (0.28-0.38 cm3 g-1), well-graphitized carbon frameworks, and uniformly dispersed Ni nanoparticles (7-15 nm) embedded in the carbon pore walls. The prepared materials show very high performance in the selective (∼84%) electrocatalytic reduction of aromatic ketones into alcohols (∼79%).