Chemical looping hydrogen generation (CLHG), as a new technology involved in chemical looping combustion (CLC) process and steam-iron process, has attracted attention for clean energy generation and efficient energy conversion. A systematic investigation of spinel NiFeAlO 4 has led to characterization of a well-defined self-supported oxygen carrier which was prepared by solid state reaction. The redox behavior of NiFeAlO 4 shows the enhancement on the resistance to agglomeration exceeding previously reported CLC process using similar compositions including Fe 2 O 3 , NiO and NiFe 2 O 4 without any inert support. Moreover, the high CO 2 conversion and H 2 generation by NiFeAlO 4 oxygen carrier under a fixed-bed reactor (FxBR) were obtained. The reaction mechanism of NiFeAlO 4 subjected to the isothermal stepwise reduction in a sequence of varying durations by XRD was also demonstrated, which provided with a novel function of selfsupported and agglomeration-resistant characteristic in the oxygen carrier system.

The intrinsic hydrophobicity of graphite felt (GF) is typically altered for the purpose of the surface wettability and providing active sites for the enhancement of electrochemical performance. In this work, commercial GF is used as the electrodes. The GF electrode with a coated-polydopamine catalyst is achieved to enhance the electrocatalytic activity of GF for the redox reaction of vanadium ions in vanadium redox flow battery (VRFB). Materials characteristics proved that a facile coating via atmospheric pressure plasma jet (APPJ) to alter the surface superhydrophilicity and to deposit polydopamine on GF for providing the more active sites is feasibly achieved. Due to the synergistic effects of the presence of more active sites on the superhydrophilic surface of modified electrodes, the electrochemical performance toward VO2+/VO2+ reaction was evidently improved. We believed that using the APPJ technique as a coating method for electrocatalyst preparation offers the oxygen-containing functional groups on the substrate surface on giving a hydrogen bonding with the grafted functional polymeric materials.