Conductive and Elastic TiO₂ Nanofibrous Aerogels: A New Concept toward Self‐Supported Electrocatalysts with Superior Activity and Durability

Abstract

Recently,v arious titanium dioxide (TiO 2)n anostructures have received increasing attention in the fields of energy conversion and storage owingt ot heir electrochemical properties.H owever,t hese particulate nanomaterials exclusively exist in the powder form, which may cause health risks and environmental hazards.H erein we report an ovel, highly elastic bulk form of TiO 2 for safe use and easy recycling. Specifically,T iO 2 nanofibrous aerogels (NAs) consisting of resiliently bonded, flexible TiO 2 nanofibers are constructed, which have an ultralowb ulk density,u ltrahigh porosity,a nd excellent elasticity.T op romote charge transfer,t hey are subjected to lithium reduction to generate abundant oxygen vacancies,whichcan modulate the electronic structure of TiO 2 , resulting in ac onductivity up to 38.2 mS cm À1 .A saproof-ofconcept demonstration, the conductive and elastic TiO 2 NAs serve as an ew type of self-supported electrocatalyst for ambient nitrogen fixation, achieving an ammonia yield of 4.19 10 À10 mol s À1 cm À2 and aF aradaic efficiency of 20.3 %. The origin of the electrocatalytic activity is revealed by DFT calculations.

TiO2/CeO2 Frame with Enriched Oxygen Vacancies and Hetero‐Interfaces for Efficient Electrochemical N2 Reduction

“…Furthermore, the electron paramagnetic resonance (EPR) spectrum of the TiO 2 /CeO 2 was measured because it is very sensitive to the uncoupled electrons as well as their interactions with the surrounding atoms. As shown in Figure 3b, the obvious signal at g=2.003 emerged, which is well identified for the unpaired electrons entrapped by the OVs [51] …”

Self-Supported Defect-Rich Au-Based Nanostructures as Robust Bifunctional Catalysts for the Methanol Oxidation Reaction and Oxygen Reduction Reaction in an Alkaline Medium

“…The reasons for the MOR and ORR catalytic performance of AuCu can be explained according to the following aspects. In terms of the overall structure of the catalyst, the self-supported structure is conducive to the transport of reactants and the improvement of the conductivity of the catalyst [ 34 ]. In more detail, a large number of defects in the kink are favorable for the adsorption of reactants; using MOR as an example, as shown in Figure 8 a and Figure S6 , in the electrochemical process, the removal of Cu from the surface occurred, which could lead to the formation of more low-coordinated Au and could enhance the adsorption of methanol on the active site and gradually improve the activity of MOR [ 35 ].…”