查看更多>>摘要：? 2022 The AuthorsNickel phthalocyanine (NiPc) can be at first glance a compelling catalyst for CO2 reduction reaction (CO2RR) because of its Ni–N4 site. Unfortunately, the pristine NiPc possesses a low catalytic activity resulting from the poor CO2 adsorption and activation capabilities of the electron-deficiency Ni site. Herein, we develop nickel polyphthalocyanine (NiPPc) with extended conjugation to tailor the electronic density at the Ni active site. The enlarged π conjugation of NiPPc evokes the d-electrons localization, increasing the electronic density at the Ni site, which enhances its CO2 adsorption and activation. Consequently, NiPPc supported on carbon nanotubes (NiPPc/CNT) in a flow cell delivers an excellent activity of ?300 mA cm?2 for CO2RR with the CO selectivity of 99.8%, which is much higher than that of NiPc dispersed on carbon nanotubes. NiPPc/CNT exhibits an outstanding stability for CO2RR of more than 30 h at a current density of ?100 mA cm?2 with an ultrahigh selectivity for CO, exceeding 99.7%. This work showcases a new way of tuning the electronic density of catalytic sites.
查看更多>>摘要：? 2022 Elsevier B.V.Electrochemical reduction of nitrate (NO3-) to ammonia (NH3) offers a sustainable avenue to close the NO3- cycle for NH3 synthesis. Critical to the feasibility of electrochemical NO3--to-NH3 technology is the development of cost-effective, scalable and selective catalysts that can produce NH3 with high yield. To this end, we design and constructure ultralow-content Pd (2.93 at%) in-situ incorporated Cu2O corner-etched octahedra (Pd-Cu2O CEO) with cavity and oxygen vacancy defects for selectively electrochemical NO3--to-NH3 transformation. The unique conner-etched cavity structure, rich surface oxygen vacancies, and Pd-Cu2O dual active sites, synergistically promote nitrate electroreduction undergo ammonia formation reaction pathway. Impressively, the as-made Pd-Cu2O CEO exhibited outstanding activity for electrocatalytic NO3--to-NH3, with high ammonia selectivity (95.31%) and Faradaic efficiency (96.56%). The developed hierarchical-defect strategy may open a new avenue for reasonable design of defect electrocatalysts to contribute desirable properties and functionalities in specific applications.
查看更多>>摘要：? 2022 Elsevier B.V.Herein, we significantly accelerated the kinetics of hydrogen evolution reaction (HER) by interfacially bonding ruthenium nanoparticles with defect-rich nitrogen and phosphorus co-doped carbon nanosheets (Ru/D-NPC). The optimal Ru/D-NPC therefore achieves ultralow overpotentials of 23, 61, and 68 mV at the current density of 10 mA cm?2 for HER in alkaline, neutral, and acidic electrolytes, respectively, demonstrating the excellent pH-universal HER activities. Specially, our Ru/D-NPC catalysts represent a 2 × advance in mass activity (639.9 mA/mgRu) compared to benchmarking Pt/C catalysts (320 mA/mgPt) and high per-site activity (0.13 s?1) under alkaline conditions while remaining the excellent stability under all pH conditions. We experimentally demonstrated that Ru-N bonds at the interfaces of Ru/D-NPC strengthen the metal-support interaction and modulates the electronic structure of Ru, optimizing the intrinsic HER kinetics and sintering-resistance of active Ru species, as further rationalized by theoretical calculations. This work shines the light on the effect of interfacial bonds on the intrinsic HER kinetics.
查看更多>>摘要：? 2022 Elsevier B.V.Energy level matching and structural stabilization of semiconductor electrode materials are critical for improving the efficiency and durability of bifunctional catalysts for photo-enhanced rechargeable Zn-air batteries. We developed a photoactive bifunctional air-electrocatalyst comprising n-type g-C3N4 and p-type copper-doped ZIF-67 (CuZIF-67) composite. g-C3N4/CuZIF-67 exhibits wide-range solar spectrum absorption and enhanced electron–hole pairs separation efficiency owing to synergistic effects of a suitable bandgap width, staggered p-n heterojunction band gap structure, and built-in electric field at its p-n heterojunction, leading to higher oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) activities compared with single p- and n-type catalysts. It has photo-enhanced charge/discharge abilities, has a voltage gap of 0.81 V under 1-sun-illumination, and maintains stable cycling with 60% round-trip efficiency under illumination over 1000 cycles for 336 h at 2 mA cm?2. In conclusion, staggered p-n heterojunction and pyrrolic nitrogen-rich groups are important for efficient and durable photo-enhanced Zn air batteries.
查看更多>>摘要：? 2022 Elsevier B.V.Designing and fabricating well-defined heterointerface catalysts with high electrocatalytic performance for oxygen evolution reaction (OER) at the industrial grade current density still remains a huge challenge. Here the flower-like nanosheets with rich Fe2O3/NiFe-layered double hydroxides (LDHs) heterointerfaces were fabricated, and they exhibit superior catalytic activity with a very low overpotential of 220 mV for OER at the industrial grade current density of 500 mA cm? 2 and fast reaction kinetics with a small Tafel slope of 32 mV dec?1. Based on the analyses of operando Raman spectra, DFT theoretical calculations and electrochemical characterizations, the superior electrocatalytic performance of catalysts for OER at the industrial grade current density can be attributed to Fe2O3/NiFe-LDHs heterointerfaces that can obviously promote interfacial electron transfer from Ni2+ to Fe3+ and optimize d-orbit electronic configuration with eg occupancy of Ni close to the unity, resulting in moderate adsorption/desorption energies of oxygenated intermediates, and thus facilitating remarkably electrocatalytic performance and superior intrinsic kinetics for OER in alkaline media.
查看更多>>摘要：? 2022 Elsevier B.V.The catalytic hydrogenation of CO2 to methanol depends significantly on the structures of metal-oxide interfaces. We show that doping a high-valency metal, viz. tungsten, to CeO2 could render improved catalytic activity for the hydrogenation of CO2 on a Cu/CeW0.25Ox catalyst, whilst making it more selective towards methanol than the undoped Cu/CeO2. We experimentally investigated and elucidated the structural-functional relationship of the Cu/CeO2 interface for CO2 hydrogenation. The promotional effects are attributed to the irreversible reduction of Ce4+ to Ce3+ by W-doping, the suppression of the formation of redox-active oxygen vacancies on CeO2, and the activation of the formate pathway for CO2 hydrogenation. This catalyst design strategy differs fundamentally from those commonly used for CeO2-supported catalysts, in which oxygen vacancies with high redox activity are considered desirable.
查看更多>>摘要：? 2022 Elsevier B.V.High activity catalysts used for eliminating the energy barrier in water breaking-up are of great significance for accelerating those reactions retarded by water molecules dissociation. In this work, an oxygen vacancy (VO)-Ti ensemble engineering on Ru catalyst was established to boost the catalytic activity toward water dissociation. The VO in VO-Ti ensemble plays as electron promoter to transfers electrons to surface Ru atoms. The rich electron state of Ru boosts the catalytic activity toward water dissociation. As an experimental verification, the turnover frequency of 1.5-RTVO-4 in ammonia borane hydrolysis reaches up to 1370 min?1 (9710 min?1 depend on the dispersion of Ru), exceeding the benchmark value set up by Ru-based catalysts. This research provides a novel electronic tuning strategy for VO as imaginary atom via electron promoter effect to enhance the intrinsic catalytic activity of metal catalysts toward inert molecule dissociation in the next generation energy chemistry field.
查看更多>>摘要：? 2022 Elsevier B.V.Perovskites are the promising catalysts for various reactions, yet their structure evolutions and the composition-function relation in the carbon dioxide reduction reaction (CO2RR) are not fully explored. In this study, we report that the reconstructed BaBiO3 (BBO) perovskite is able to facilitate CO2-to-formate (FA) conversion by both A- (Ba) and B- (Bi) site elements through the cooperative but distinct catalytic mechanisms. Specifically, the electrochemical reductions of BBO trigger the complete rearrangement of atoms with rapid kinetics at catalytically relevant voltages, giving rise to electricity-induced Bi metallene (eBBO) that efficiently generates FA with high selectivity and partial current densities. Moreover, the reconstructed BBO simultaneously enables Ba2+ release to the electrolyte, and the time-resolved FTIR and in situ Raman analysis collectively reveal that the Ba2+ adsorption enables easier CO2 adsorption, thereby leading to enhanced CO2-to-FA conversion. This work is of direct significance in elucidating the cooperative catalysis between A- and B- site elements in perovskites for room-temperature CO2RR.
查看更多>>摘要：? 2022 Elsevier B.V.Photocatalytic water pollution remediation is currently a hot issue in the field of environmental protection. However, the limited optical adsorption, recombination of electrons and holes, as well as low kinetics in solid-liquid conditions impede the further improvement in photoactivity. Inspired by the degradation mechanism of photocatalytic process, started with interfacial engineering, in this paper, plasmonic metal-semiconductor heterostructures (PMSHs) combined with an optimized dissolved oxygen transporting channel were prepared. With the synergetic help of PMSHs and superhydrophilic-superhydrophobic (superwetting) reaction interface, it is not only can realize the effective capture of photons in the visible light band, but also promote the fully separation of electron-hole pairs. The efficiency in PMSHs based triphase system is ~60 times higher than traditional solid-liquid system, and is ~3 times higher than PMSHs based solid-liquid system. The stability and wide applicability in series organic dyes degradation also made it a good potential for practical pollutants water treatment.
查看更多>>摘要：? 2022 Elsevier B.V.Tailoring the surficial chemical environment of two-dimensional materials by organic modification is an effective way to optimize their catalytic behaviors. Herein, we present a dynamic coordination approach to improve the photocatalytic performance of ultrathin Co2CO3(OH)2 nanosheets (u-CoCH) in NIR light (λ > 780 nm) driven carbonylation reaction by using the reacting substrates (diamines) as the ligands. The coordination of diamines with surface Co2+ ions form a binuclear complex at the crystallographic planes of u-CoCH. The as-formed complexes can reduce the energy barrier of carbonylation reaction by weaking the N-H bond of the substrate on u-CoCH, and afford enhanced light response as well as the prolonged photogenerated electron lifetime. Together with the successful synthesis of a series of important structural motifs in pharmaceuticals and bioactive agents, the promoted photosynthesis reaction mode via in-situ formed surface complexes offers a model toward full-spectrum-solar-energy conversion in the field of chemical synthesis.
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