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Nowadays, the development and utilization of clean energy are becoming increasingly urgent. Among them, methanol is a new, clean, and efficient energy source. Therefore, more and more studies are focusing on methanol anodic oxidation (MOR). In this work, nanoflower and hollow spherical NiO was synthesized by a simply hydrothermal method and then modified by Co ion, NiS2 and carbon nanotubes (CNTs). The optimal Co/NiO(f)/NiS2−CNT exhibits flower‐like morphology with a larger specific surface area, enlarged electrochemically active surface area and higher conductivity, which improve the electron transfer ability and electrocatalytic activity compared with pure NiO(f), NiO(f)/NiS2, NiO(f)/NiS2−CNT and hollow spherical Co/NiO(hs)/NiS2−CNT. The current density is ultrahigh of 203.46 mA ⋅ cm−2 at 0.8 V, which is 36 times higher than pure NiO(f) and almost 2 times higher than Co/NiO(hs)/NiS2−CNT. Therefore, this work offers a highly efficient and stable NiO based catalyst for methanol oxidation reaction. [ABSTRACT FROM AUTHOR]

Water pollution has posed a serious threat to the environment and human health. There is an urgent need to develop highly efficient and application‐convenient photocatalytic materials. To overcome this critical problem, the carbonized nickel‐loaded spent coffee grounds modified BiOCl (CNSCG‐BOC‐8) photocatalyst is prepared by using facile calcination and hydrolysis method. The optimum substrate carbonization temperature, the amount of substrate, and the loading amount of nickel ion are discussed. Further, the photocatalytic performance of the catalyst is tested using Ofloxacin (OFX) as target pollutant under ultraviolet and visible light (UV–vis light). The as‐obtained photocatalysts show the degradation efficiency of OFX in the prepared composite reaches 87% within 40 min under ultraviolet and visible light. Moreover, the results show that CNSCG‐BOC‐8 has better photoelectricity, excellent cycle stability, and is environment‐friendly. Therefore, this paper provides an important reference for the rational development and use of Ni‐loaded biomass‐derived carbon as the substrate to modify bismuth‐based photocatalyst for environmental remediation. [ABSTRACT FROM AUTHOR]

Given that currently more high-efficiency photocatalysts are needed to address environmental pollution, this paper has proposed an effective method of P123-modified synthesis of BiOCl nanosheet/bismuth nitrate (BiOCl/BBN) heterojunctions. The photocatalytic results showed that the BiOCl nanosheet with BiOCl/BBN heterojunctions (BOC-1) exhibited 100% efficiency in the photocatalytic degradation of RhB within 3 min under visible light, simultaneously demonstrating beneficial stability and recyclability. The effectiveness of the photocatalytic activity of BOC-1 was ascribed to the formation of BiOCl/BBN heterojunctions and P123 modification, which facilitated the separation of carriers. This study offers a convenient and effective approach for the synthesis of high-efficiency heterogeneous photocatalysts for the removal of environmental pollutants. [ABSTRACT FROM AUTHOR]

Water electrolysis operating in alkaline environments is a promising route to produce H2 on a massive scale. In this context, designing highly‐active and low‐cost electrocatalysts is of great importance. Here NiPt alloys with plenty of atomically dispersed Pt at the edges to boost hydrogen evolution in alkaline solution are reported. The formed Ni‐Pt atomic pairs at the edges hold engineered electronic structures by reducing the number of coordination atoms to facilitate the kinetically sluggish Volmer step, and further promote the hydrogen coupling step by providing separate active sites as well. With a Pt content of 3at%, this catalyst records an ultralow overpotential of 6 mV to reach the current density of 10 mA cm−2, and delivers a current density of 68.3 mA cm−2 at the overpotential of 30 mV, exceeding that of the commercial 20wt% Pt/C catalyst by a factor of >4. The aberration‐corrected transmission electron microscopy and quasi‐operando X‐ray absorption fine structure measurements show Ni‐Pt atomic pairs serve as active sites and enable the subtle adsorption/desorption balances between various intermediates (OH* and H*) during the hydrogen evolution reaction. The as‐made alloys show high stability with negligible activity decay after a 12 h chronoamperometric test, addressing its feasibility in an overall water‐splitting cell. [ABSTRACT FROM AUTHOR]

Ni-based heterostructures have been regarded as promising catalysts for the hydrogen evolution reaction (HER) in alkaline solutions due to its high efficiency in catalyzing the water dissociation process. Therefore, an in-depth understanding of the water-dissociation-related activity of Ni species within varied structures and coordination environments is significant for the design of novel catalysts. Herein, we synthesized three types of Ni-based heterostructures, namely NiS/MoS2, NiSe/MoS2 and NiSe2/MoS2 by a controllable route to investigate their catalytic trends and origins of the HER under alkaline conditions. Combined with experimental data and theoretical calculation results, we revealed that the alkaline HER activity of the heterostructures relies on the catalyzing ability of Ni species in the Volmer step, which is associated with the d-band center, and is further related to the coordination condition of the Ni atoms in the chalcogenides. With the highest valence state and d-band center among the samples, Ni atoms in NiS exhibit the fastest reaction rate in the Volmer step, thus providing the best catalytic activity for the NiS/MoS2 heterostructure in the alkaline HER. Furthermore, an activity trend for the Ni chalcogenides in the Volmer step, in the order of NiS > NiSe2 > NiSe, has been proposed, which is expected to contribute insights into the design of novel heterostructured catalysts. [ABSTRACT FROM AUTHOR]

• Ternary NiMoCo alloys and fluffy carbon nanotubes grown on ZIF-67-derived polyhedral carbon frameworks. • Evaporated Ni(DMG)2 provides favorable reduction atmosphere for alloy formation during pyrolysis. • The synergistic effect of NiMoCo ternary alloy and fluffy carbon nanotubes contributes to high catalytic performance. • ZIF-67DC/NiMoCo/CNT catalysts display outstanding catalytic performance for HER and OER. • The cell voltage required for water splitting was found to be ∼1.64 V at 10 mA cm−2 in alkaline medium. The synthesis of efficient and stable non-precious metal electrocatalytic materials is one of the main challenges in current overall water splitting research. Herein, this paper puts forward a facile pyrolysis synthesis strategy for the construction of ZIF-67DC/NiMoCo/CNT ternary alloy catalyst with three-dimensional nanostructure and abundant fluffy carbon nanotubes. Benefiting from the synergistic effect between NiMoCo ternary alloy and carbon nanotubes, the ZIF-67DC/NiMoCo/CNT bifunctional catalyst can yield current density of 10 mA cm−2 at overpotentials of 85 mV and 306 mV over HER and OER in alkaline medium, respectively. The overall water splitting device can deliver current densities of 10 mA cm−2 for long periods of time at drive voltages as low as 1.64 V with nearly negligible decay in potential. This study provides a novel and operable method for the design of non-precious metal electrocatalysts. [Display omitted] [ABSTRACT FROM AUTHOR]