Transition‐metal alloys are currently drawing increasing attention as promising electrocatalysts for the alkaline hydrogen evolution reaction (HER). However, traditional density‐functional‐theory‐derived d‐band theory fails to describe the hydrogen adsorption energy (ΔGH) on hollow sites. Herein, by studying the ΔGH for a series of Ni−M (M=Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, W) bimetallic alloys, an improved d‐band center was provided and a potential NiCu electrocatalyst with a near‐optimal ΔGH was discovered. Moreover, oxygen atoms were introduced into Ni−M (O−NiM) to balance the adsorption/desorption of hydroxyl species. The tailored electrocatalytic sites for water dissociation can synergistically accelerate the multi‐step alkaline HER. The prepared O−NiCu shows the optimum HER activity with a low overpotential of 23 mV at 10 mA cm−2. This work not only broadens the applicability of d‐band theory, but also provides crucial understanding for designing efficient HER electrocatalysts.

We constructed a cholesteric liquid crystal/polymer network system and studied the aligning effects of the polymer network on the liquid crystal. We stabilized different liquid crystal states by varying the polymer concentration. Using a proper polymer network, we developed a bistable polymer stabilized cholesteric texture (PSCT) light shutter at zero field. The PSCT light shutter is switched to a transparent state by a voltage and remains transparent after removal of the voltage. When the shutter is heated to elevated temperatures, it is switched into a scattering state and remains scattering when cooled to low temperatures.

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