Electrochemical reduction of CO2 to valuable fuels is appealing for CO2 fixation and energy storage. However, the development of electrocatalysts with high activity and selectivity in a wide potential window is challenging. Herein, atomically thin bismuthene (Bi‐ene) is pioneeringly obtained by an in situ electrochemical transformation from ultrathin bismuth‐based metal–organic layers. The few‐layer Bi‐ene, which possesses a great mass of exposed active sites with high intrinsic activity, has a high selectivity (ca. 100 %), large partial current density, and quite good stability in a potential window exceeding 0.35 V toward formate production. It even deliver current densities that exceed 300.0 mA cm−2 without compromising selectivity in a flow‐cell reactor. Using in situ ATR‐IR spectra and DFT analysis, a reaction mechanism involving HCO3− for formate generation was unveiled, which brings new fundamental understanding of CO2 reduction.

The combination of lone-pair effects on Pb(2+) cations and the smaller electronegativity of I(-) anions into the pentaborate framework generates a phase-matchable material, Pb(2)B(5)O(9)I, with the largest powder SHG response among borates, about 13.5 times that of KDP (KH(2)PO(4)), and transparency over the near-UV to middle-IR region. DFT calculations on electronic structure and cutoff-energy-dependent SHG coefficients confirm these origins.

No abstract

Herein, the authors report, for the first time, the semisacrificial template growth of a self‐supporting metal–organic framework (MOF) nanocomposite electrode composed of ultrasmall iron‐rich Fe(Ni)‐MOF cluster‐decorated ultrathin Ni‐rich Ni(Fe)‐MOF nanosheets from the NiFe alloy foam, in which the Fe(Ni)‐MOF clusters are uniform with a particle size of 2–5 nm, while the thickness of the Ni(Fe)‐MOF nanosheets is only about 1.56 nm. When directly used as a self‐supported working electrode for the oxygen evolution reaction (OER), it can afford an impressive electrocatalytic performance with required overpotentials of 227 and 253 mV to achieve current densities of 10 and 100 mA cm−2, respectively, much outperforming the benchmark of RuO2 and most state‐of‐the‐art noble‐metal‐free catalysts. Characterizations demonstrated that the combination of the unique nanostructure of the catalyst and the strong coupling effect between Ni and Fe active sites should be responsible for its excellent OER performance. Remarkably, when coupled with a Pt electrode in an overall water splitting system, they only needed 1.537 V to achieve a current density of 10 mA cm−2. The facile and economical methodology represents a new way to design and prepare high‐performance self‐supporting MOF electrocatalysts for highly efficient electrochemical processes.

Two-dimensional (2D) materials have been studied extensively as monolayers, vertical or lateral heterostructures. To achieve functionalization, monolayers are often patterned using soft lithography and selectively decorated with molecules. Here we demonstrate the growth of a family of 2D materials that are intrinsically patterned. We demonstrate that a monolayer of PtSe can be grown on a Pt substrate in the form of a triangular pattern of alternating 1T and 1H phases. Moreover, we show that, in a monolayer of CuSe grown on a Cu substrate, strain relaxation leads to periodic patterns of triangular nanopores with uniform size. Adsorption of different species at preferred pattern sites is also achieved, demonstrating that these materials can serve as templates for selective self-assembly of molecules or nanoclusters, as well as for the functionalization of the same substrate with two different species.

Electrochemical CO2 reduction reaction (CO2RR) to value-added and readily collectable liquid products is promising but remains a great challenge due to the lack of efficient and robust electrocatalysts. Herein, a...

No abstract

Electrosynthesis of formic acid/formate is a promising alternative protocol to industrial processes. Herein, a pioneering pair‐electrosynthesis tactic is reported for exclusively producing formate via coupling selectively electrocatalytic methanol oxidation reaction (MOR) and CO2 reduction reaction (CO2RR), in which the electrode derived from Ni‐based metal–organic framework (Ni‐MOF) nanosheet arrays (Ni‐NF‐Af), as well as the Bi‐MOF‐derived ultrathin bismuthenes (Bi‐enes), both obtained through an in situ electrochemical conversion process, are used as efficient anodic and cathodic electrocatalysts, respectively, achieving concurrent yielding of the same high‐value product at both electrodes with greatly reduced energy input. The as‐prepared Ni‐NF‐Af only needs quite low potentials to reach large current densities (e.g., 100 mA cm−2@1.345 V) with ≈100% selectivity for anodic methanol‐to‐formate conversion. Meanwhile, for CO2RR in the cathode, the as‐prepared Bi‐enes can simultaneously exhibit near‐unity selectivity, large current densities, and good stability in a wide potential window toward formate production. Consequently, the coupled MOR//CO2RR system based on the distinctive MOF‐derived catalysts displays excellent performance for pair‐electrosynthesis of formate, delivering high current densities and nearly 100% selectivity for formate production in both the anode and the cathode. This work provides a novel way to design advanced MOF‐derived electrocatalysts and innovative electrolytic systems for electrochemical production of value‐added feedstocks.