Xia Wei,Bing Fang,Tianyao Wang,Hongbin Dai,Song Li
Understanding the metal-support interaction between Rh-B and CeO 2 is essential for enhancing the efficiency of hydrogen generation from hydrous hydrazine. In this study, a series of Rh-B/CeO 2 catalysts were synthesized via a facile wet-chemical reduction method. The Rh-B/(CeO 2 ) 0.7 catalyst exhibits a remarkable 12-fold increase in turnover frequency (TOF) compared to pristine Rh-B catalyst. The strong electronic coupling between Rh-B and CeO 2 was identified as the primary factor driving this significant performance enhancement. This interaction facilitates the formation of oxygen vacancies, promoting hydrazine adsorption and subsequent cleavage of the N-H bond in N 2 H 4 * to form N 2 H 3 *. Our findings emphasize the pivotal role of support engineering in catalyst design for optimizing catalytic performance.
Hydrous hydrazine (N2H4·H2O) is considered to be a promising chemical hydrogen storage carrier due to its high hydrogen content (8.0 wt%), production of only N2 in addition to H2, and facile recharging as a stable liquid. In this work, for the first time, CoPt NPs supported on La(OH)3 are used as a highly effective catalyst for selective decomposition of N2H4. Surprisingly, the La(OH)3 nanosheet-supported CoPt NPs exhibit superior catalytic performance, releasing 3 equiv. (H2 + N2) with turnover frequency (TOF) values of up to 734.2 h−1 at 303 K and 2400 h−1 at 323 K; these are higher than those of most reported catalysts for the dehydrogenation of N2H4. Especially, CoPt/La(OH)3 can be easily separated from the reaction solution using a magnet due to its super-paramagnetic nature, and it can maintain its high activity and 100% selectivity even after five cycles. The high performance of CoPt/La(OH)3 can be attributed to the electronic interaction between Co and Pt, strong basic sites on the surface of La(OH)3 and a synergistic cooperative effect between the ultrafine CoPt NPs and the La(OH)3 support. The development of a high performance Co-based catalyst may promote the effective application of hydrous hydrazine as a promising hydrogen storage material.
Fuhua Xu,Yanlan Wang,Changlong Wang,Wenkai Huang,Xiang Liu
In despite of significant progresses have been accomplished in the programming and development of updated and efficient nana-catalysts for H 2 production from a wide variety of chemical hydrogen storage materials. However, it is a practical matter of the utmost importance to develop the “on-off” control for on demand H 2 release in the cause of effectively and safely producing, carrying and depositing H 2 gas. Herein, we have first designed and synthesized a sequence of carbon nanosphere (CNS)-stabilized bimetallic PtNi nanoparticles (PtNi/CNS), by stabilization of nearly monodispersed PtNi bimetallic nanoparticles onto the surface of carbon nanosphere, for the highly selective and efficient on-demand H 2 release upon the dehydrogenation of hydrous hydrazine. Then, the optional nanocatalyst Pt 1 Ni 1 /CNS exhibits the highest catalytic performance in hydrogen production from dehydrogenation of hydrous hydrazine, with 100 % H 2 selectivity and the turnover frequency (TOF) of 3928 mol (H 2 )·mol cat −1 ·h −1 at 50 °C. The detailed physical characterizations have confirmed that the superior catalytic performance of Pt 1 Ni 1 /CNS in the H 2 release upon hydrous hydrazine dehydrogenation is attributed to the electronic interaction and synergistic effect between Ni and Pt. More importantly, the highly selective “on-off” control for demand-based H 2 release upon the dehydrogenation of hydrous hydrazine is successfully realized by pH regulation.
Ultrafine NiPtP nanoparticles (NPs) assembled on reduced graphene oxide (rGO) have been synthesized by a co-reduction route using sodium hypophosphite (NaH 2 PO 2 ) as the source of the nonmetallic P. The well-dispersed ultrafine NiPtP NPs with a diameter about 2 nm can be readily obtained. It is found that these catalysts demonstrate high selectivity and excellent catalytic activity for the decomposition of N 2 H 4 ·H 2 O at mild temperature. The enhanced catalytic performance can be attributed to synergistic effect of P-doping and strong high selectivity interaction with graphene support.
危险品化学品经营许可证（带存储）