A novel phosphorus‐containing porous polymer is efficiently prepared from tris(4‐vinylphenyl)phosphane by radical polymerization, and it can be easily ionized to form an ionic porous polymer after treatment with hydrogen iodide. Upon ionic exchange, transition‐metal‐containing anions, such as tetrathiomolybdate (MoS4 2−) and hexacyanoferrate (Fe(CN)6 3−), are successfully loaded into the framework of the porous polymer to replace the original iodide anions, resulting in a polymer framework containing complex anions (termed HT‐Met, where Met = Mo or Fe). After pyrolysis under a hydrogen atmosphere, the HT‐Met materials are efficiently converted at a large scale to metal‐phosphide‐containing porous carbons (denoted as MetP@PC, where again Met = Mo or Fe). This approach provides a convenient pathway to the controlled preparation of metal‐phosphide‐loaded porous carbon composites. The MetP@PC composites exhibit superior electrocatalytic activity for the hydrogen evolution reaction (HER) under acidic conditions. In particular, MoP@PC with a low loading of 0.24 mg cm−2 (on a glass carbon electrode) affords an iR‐corrected (where i is current and R is resistance) current density of up to 10 mA cm−2 at 51 mV versus the reversible hydrogen electrode and a very low Tafel slope of 45 mV dec−1, in rotating disk measurements under saturated N2 conditions.

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We theoretically investigate the absorption spectra, dipole polarizabilities, and first-order hyperpolarizabilities of SiC(n) and Si(n)C (n=2-6) clusters using the density functional response approach. Similar to other semiconductor clusters such as Si and gallium arsenide (GaAs) clusters, the absorption spectra of the SiC(n) and Si(n)C clusters show long absorption tails in the low-transition-energy region and strong absorption peaks in the high-transition-energy region (>4.0 eV). For the same n, the absorption spectrum of the Si(n)C cluster is blueshifted with respect to that of the SiC(n) cluster, which may be related to the larger highest occupied molecular orbital-lowest unoccupied molecular orbital gap in the former. The isotropic (alpha) dipole polarizabilities of the SiC(n) and Si(n)C clusters are larger than the bulk polarizability of 3C-SiC and lie between the dipole polarizabilities of Si and C. The SiC(n) clusters have lower dipole polarizabilities and larger first-order hyperpolarizabilities than the Si(n)C clusters. The size dependence of the first-order hyperpolarizabilities of the SiC(n) clusters, which have approximate Si-terminated linear chain geometry, is similar to that observed in pi-conjugated organic molecules.

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