Although atomically precise metal nanoclusters (NCs) are widely used in catalysis, a wide gap exists between state‐of‐the‐art performance and practical requirements. Regulating the intrinsic activity of NCs is critical for the rational design and synthesis of highly efficient catalysts. Herein, M4Ni2 NCs (M = Au, Ag) with improved electrocatalytic nitrogen reduction reaction (NRR) activity due to the introduction of Ni are synthesized, which significantly suppresses the H2 generation competition reaction. Ag4Ni2 NCs exhibit the best NRR activity at −0.2 V versus RHE with a NH3 yield of 23.32 µg mg–1 h–1 and a faradic efficiency of 78.97% due to the higher N2 chemisorption ability and lower rate‐determining barrier. Meanwhile, ligand partial detachment of NCs during electrocatalysis offers exposed active sites and induces the charge reconstruction, also contributing to the outstanding NRR performance. Based on the precise composition and structure, deep insights into the NRR mechanism at the atom level are provided by in situ Fourier‐transformed infrared spectroscopy and ab initial calculation. The study presents an efficient strategy based on heteroatom doping and charges reconstruction to promote NCs catalytic performance.

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Graphite oxide and its exfoliated counterpart, graphene oxide, are important precursors for the large‐scale production of graphene‐based materials and many relevant applications. The current batch‐style preparation of graphite oxide suffers from safety concern, long reaction time, and nonuniform product quality, due to the large volume of reactors and slow energy exchange. Reaction in microchannels can largely enhance the oxidization efficiency of graphite due to the enhanced mass transfer and extremely quick energy exchange, by which the controllable oxidization of graphite is achieved in ≈2 min. Comprehensive characterizations show that the graphene oxide obtained through the microfluidic strategy has features like those prepared in laboratory beakers and industrial reactors, yet with the higher oxidization degree and more epoxy groups. More importantly, the microfluidic preparation allows for on‐line monitoring of the oxidization by Raman spectroscopy, ready for the dynamical control of reaction condition and product quality. The capability of continuous preparation is also demonstrated by showing the assembly of fibers and reduction of graphene oxide in microfluidic channels, and the applicability of graphene oxide prepared from the microfluidic strategy for thermally and electrically conductive films.