The oxygen reduction reaction (ORR) is of significant importance in the development of fuel cells. Now, cobalt-nitrogen-doped chiral carbonaceous nanotubes (l/d-CCNTs-Co) are presented as efficient electrocatalysts for ORR. The chiral template, N-stearyl-l/d-glutamic acid, induces the self-assembly of well-arranged polypyrrole and the formation of ordered graphene carbon with helical structures at the molecular level after the pyrolysis process. Co was subsequently introduced through the post-synthesis method. The obtained l/d-CCNTs-Co exhibits superior ORR performance, including long-term stability and better methanol tolerance compared to achiral Co-doped carbon materials and commercial Pt/C. DFT calculations demonstrate that the charges on the twisted surface of l/d-CCNTs are widely separated; as a result the Co atoms are more exposed on the chiral CCNTs. This work gives us a new understanding of the effects of helical structures in electrocatalysis.

The development of efficient bifunctional electrocatalysts for the oxygen reduction reaction( ORR) and oxygen evolution reaction( OER) still remains ac hallenge in aw ide range of renewable energy technologies. Herein, CuCo alloy nanoparticlese ncapsulatedb yn itrogen-doped carbonaceous nanoleaves (CuCo-NC) have been synthesized from aC u(OH) 2 /2D leaf-like zeolitic imidazolate framework (ZIF-L)-pyrolysis approach. Leaf-like Cu(OH) 2 is first prepared by the ultrasound-induced self-assembly of Cu(OH) 2 nanowires. The efficient encapsulation of Cu(OH) 2 in ZIF-L is ob-tained owing to the morphologyf itting between the leaflike Cu(OH) 2 and ZIF-L. CuCo-NC catalysts present superior electrocatalytic activity and stability toward ORR and OER over the commercial Pt/C and IrO 2 ,r espectively,w hich are furtheru sed as bifunctionalo xygen electrocatalysts in Zn-air batteries and exhibit impressive performance,w ith ah igh peak powerdensity of 303.7 mW cm À2 ,large specific capacity of up to 751.4 mAh g À1 at 20 mA cm À2 ,a nd as uperior recharge stability.

Hierarchical Zn-doped CoO nanoflowers have been prepared using their hydroxides as precursors. The nanoflowers are assembled by dozens of 2D nanoplates. Each nanoplate is formed by numerous Zn-doped CoO nanoparticles. Zn-doped CoO catalyst is highly efficient for electrocatalytic water oxidation with a low overpotential (η = 293 mV at j = 10 mA cm À 2 ) and long-term stability, which is comparable to the commercial RuO 2 catalysts in alkaline media. The 3D hierarchical structure provides abundant surface catalytic sites, while the density functional theory (DFT) calculations show that the Zn doping is also beneficial for the enhanced oxygen evolution reaction (OER) activities. This series of novel hierarchical porous nanoflowers is a promising anode material for water oxidation.

Two-dimensional (2D) metal-organic frameworks (MOFs) have become a hot topic recently for their high surface areas, larger number of exposed active sites, and improved conductivity. Combination of different 2D MOFs...

The oxygen reduction reaction (ORR) is of significant importance in the development of fuel cells.Now,cobaltnitrogen-doped chiral carbonaceous nanotubes (l/d-CCNTs-Co) are presented as efficient electrocatalysts for ORR. The chiral template,N -stearyl-l/d-glutamic acid, induces the selfassembly of well-arranged polypyrrole and the formation of ordered graphene carbon with helical structures at the molecular level after the pyrolysis process.C ow as subsequently introduced through the post-synthesis method. The obtained l/ d-CCNTs-Co exhibits superior ORR performance,i ncluding long-term stability and better methanol tolerance compared to achiral Co-doped carbon materials and commercial Pt/C.DFT calculations demonstrate that the charges on the twisted surface of l/d-CCNTs are widely separated;a sar esult the Co atoms are more exposed on the chiral CCNTs.T his work gives us an ew understanding of the effects of helical structures in electrocatalysis.