Ammonium dihydrogen phosphate (NH4H2PO4) was used as an activator and co-dopant to induce the synthesis of N, P co-doped porous carbon nanosheets (NPCNs) from pomelo peel for using as high-performance supercapacitors. Pomelo peel has a unique sponge-like structure in which NH4H2PO4 particles can be evenly embedded. The pore structure and heteroatomic doping amount of NPCNs were controlled by adjusting the pyrolysis temperature. As a result, the optimal sample exhibits high specific capacitance (314 +/- 2.6 F g(-1)) and rate capability (82% of capacitance retention at 20 A g(-1)). NPCNs750 was further employed in a symmetrical supercapacitor (NPCNs-750//NPCNs-750 SSC) with 2 M Li2SO4 electrolyte, and exhibits a high energy density of 36 +/- 1.5 W h kg(-1) at a power density of 1000 W kg(-1), with excellent cycling stability with 99% retention after 10,000 cycles. A series of excellent results show that this pollution-free and cost-effective method can be used for the design and preparation of high-performance supercapacitor electrode materials. (C) 2021 Elsevier Inc. All rights reserved.

Low-cost non-noble metal catalyst for dehydrogenation of formic acid to hydrogen at near room temperature is considered as a key to promoting commercial technology for clean energy. We have constructed reduced graphene oxide (RGO) self-assembly bonded nickel particles for synthesis of graphene nanosheets embedded with nickel nanoparticles architecture Ni@xRGO. Nitrogen and oxygen co-doped graphene facilitates the adsorption of hydrogen protons from formic acid. Electron transfer ability of Ni@xRGO with active sites is enhanced via Ni-C bond in the interface between the RGO nanosheets and nickel particles, which promoted the C-H bond breaking for dehydrogenation of formic acid. The Ni@0. 20RGO has excellent catalytic performance for hydrogen production from formic acid at near room temperature (the yield of hydrogen, 240.0 mL g-1 h-1 at 50 degrees C), comparable to the most active non-noble metal catalysts. (c) 2021 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.

An effective and low-cost nanocatalyst is designed for formic acid (FA) dehydrogenation to boost practical applications. Herein, we report superior PdCoNi nanoparticles (NPs) supported on Schiff base conjugated carbon nitride, which exhibits excellent catalytic performance with a turnover frequency (TOF) of 1308 h(-1) on FA decomposition to hydrogen at room temperature. The results show that the Schiff base groups grafted on the carbon nitride support contribute to providing abundant conjugated active sites for anchoring metal, leading to the formation of ultrafine and well-dispersed PdCoNi NPs (1.70 nm) with electron-rich Pd species, which are responsible for the outstanding catalytic activity. The conjugated Schiff base can also facilitate the O-H bond dissociation on FA, which further promotes the decomposition of FA. This low-cost and high-performance palladium-based catalyst is conducive to the development of composite catalysts on FA dehydrogenation.

以氮修饰的炭黑为载体制备负载型PdCu/N-CB系列催化剂,相比较于未经氮修饰的催化剂,其催化性能显著提高,其中Pd8Cu2/N-CB催化剂活性最高,TOF为718.56 h-1,并呈现良好稳定性.通过XRD、TEM、FTIR和XPS等表征分析,结果表明,经APTMS处理所制得的氮修饰载体N-CB促进了所负载的PdCu合金纳米颗粒变得细小并呈现良好的分散性,活性相PdCu合金与氮修饰的载体N-CB之间存在强相互作用,调变合金颗粒表面化学态,提高了催化剂催化甲酸分解制氢性能.通过引入过渡金属和氮修饰载体来改善负载型贵金属催化剂催化性能的方法有助于低成本高性能制氢催化剂开发.