Xiaoling Hong,Qilu Yao,Jianjun Long,Xiugang Li,Xiangshu Chen,Zhang-Hui Lu
Hydrous hydrazine (N2H4·H2O) has great potential as a convenient and safe hydrogen source for fuel cells. Tremendous efforts have been made to develop economic and efficient metal catalysts for hydrogen evolution from N2H4·H2O, but it remains a huge challenge. Herein, for the first time, noble-metal-free CuNi nanoparticles (NPs) immobilized on lanthanum oxycarbonate/reduced graphene oxide nanocomposites (CuNi/La2O2CO3/rGO) were successfully fabricated through an impregnation-reduction approach. Well-dispersed and ultrafine CuNi alloy NPs (∼3.2 nm) can be easily anchored onto La2O2CO3/rGO, and the aggregation of metal NPs can be effectively avoided. Benefiting from the small metal NP size, the synergistic effect between Cu and Ni, and the strong metal–support interactions, the Cu0.5Ni0.5/La2O2CO3/rGO nanocomposites (NCs) exhibited remarkably improved catalytic activity and 100% H2 selectively toward N2H4 decomposition, outperforming Cu/La2O2CO3/rGO, Ni/La2O2CO3/rGO, CuNi/rGO, and CuNi/La2O2CO3. The total turnover frequency of Cu0.5Ni0.5/La2O2CO3/rGO catalyst reached up to 114.3 h–1 at 343 K, indicating that the Cu0.5Ni0.5/La2O2CO3/rGO is one of the most active noble-metal-free catalysts ever reported for the same reaction. The low-cost and outstanding catalytic activity of CuNi/La2O2CO3/rGO NCs improved the feasibility of using N2H4·H2O as a chemical hydrogen carrier and is expected to be applied in economic hydrogen-based fuel cells.
Shuangtian Dong,Dongyang Wang,Xuwen Gao,Li Fu,Jingna Jia,Yuqi Xu,Bin Zhang,Guizheng Zou
All commercial chemiluminescence (CL) assays are conducted with either glow or flash CL of eye-visible waveband from chemical luminophores. Herein, glow and flash, as well as waveband adjustable CL from the same nanoparticle luminophore of thiol-capped CuInS2@ZnS nanocrystals (CIS@ZnS-Thiol), are proposed via extensively exploiting the differed redox nature of CL triggering reagents. Taking thiosalicylic acid (TSA) as the model thiol-capping agent, the electron-injection-initiated charge transfer between CIS@ZnS-TSA and reductant can bring out efficient glow CL while the hole-injection-initiated charge transfer between CIS@ZnS-TSA and oxidant can give off obvious flash CL under optimum conditions. The maximum emission wavelength for CL of CIS@ZnS-TSA is adjustable from 730 nm to 823 nm via employing different triggering agents. Promisingly, the coexistent reductant of N2H4·H2O and oxidant of H2O2 can be employed as dual triggering reagents to trigger eye-visible and highly efficient flash CL from CIS@ZnS-TSA. The maximum emission intensity for flash CL of CIS@ZnS-TSA/N2H4–H2O2 is 101-fold greater than the glow CL of CIS@ZnS-TSA/N2H4 and 22-fold greater than the flash CL of CIS@ZnS-TSA/H2O2, respectively. The flash CL from CIS@ZnS-TSA/N2H4–H2O2 is qualified for highly sensitive and selective CL immunoassay in a commercialized typical procedure with the entire operating process manually terminated within 35 min.
Ni/La 2 O 3 nanocatalyst with Pt and Rh content as low as 5 mol%, respectively, is successfully synthesized by a facile co-reduction method in the presence of hexadecyl trimethyl ammonium chloride aqueous solution under ambient atmosphere. Interestingly, the resulted Ni/La 2 O 3 catalyst with low cost exhibits excellent catalytic activity to dehydrogenation of hydrous hydrazine (N 2 H 4 ·H 2 O), producing hydrogen with 100% selectivity at room temperature (298 K), which represents a promising step toward the practical application for N 2 H 4 ·H 2 O system on fuel cells.
危险品化学品经营许可证（带存储）