highly active and stable OER electrocatalysts based on rational design strategies is a critical knot along the renewable energy roadmap of converting electrical energy into fuels and chemicals. In particular, electrochemical water splitting can directly utilize the renewable electricity for efficient and clean hydrogen production. [4] The energy conversion efficiency is seriously restricted by OER processes with muti-electron transformation and complex reaction routes. [5] Given this challenge, precious metal-based oxides (IrO 2 and RuO 2 ) were developed as the mainstream electrocatalysts and exhibited high catalytic performance at the harsh reaction condition, whereas scarcity and expensiveness hinder their applications for the large-scale hydrogen production. Therefore, a key bottleneck is to develop efficient and stable earth-abundant catalysts.Ideally, OER catalysts are expected to exhibit high-density accessible active sites, high ion permeability that allows the free movement of ions, and high structural stability for long-term operation. Most metal-based OER catalysts follow a redox couple-mediated water oxidation mechanism. [6] Metal ions usually serve as redox couples to reduce the OER overpotentials. [7] An ideal OER catalyst should offer an appropriate ligand environment with active Substantial overpotentials and insufficient and unstable active sites of oxygen evolution reaction (OER) electrocatalysts limit their efficiency and stability in OER-related energy conversion and storage technologies. Here, a template editing strategy is proposed to graft highly active catalytic species onto highly conductive rigid frameworks to tackle this challenge. As a successful attempt, two types of NiO 6 units of layered Ni BDC (BDC stands for 1,4-benzenedicarboxylic acid) metal organic frameworks are selectively edited by chemical etching-assisted electroxidation to create layered γ-NiOOH with intercalated Ni-O species. In such an interlayer-confined intercalated architecture, the large interlayer space with high ion permeability offers an ideal reaction region to sufficiently expose the OER active sites comprising high-density intercalated Ni-O species, which also suppresses the undesirable γ to β phase transformation, thus exhibiting efficient and durable OER activity. As a result, water oxidation can occur at an extremely low overpotential of 130 mV and affords 1000 h stability at 100 mA cm −2 . The strategy conceptually shows the possibility of achieving stable homogeneous-like catalysis in heterogeneous catalysis.

Stability and antipoisoning effects are the main challenges for the application of commercial Pt/C catalysts. Herein, we soaked and adsorbed polydopamine to coat Pt particles on commercial Pt/C and subsequently converted the coatings to few-layer N-doped graphene by calcination to produce Pt/C@NC. The coatings effectively block the direct contact of Pt nanoparticles and electrolyte, thus enhancing the catalyst stability by avoiding Ostwald ripening and suppressing the competitive adsorption of toxicants, contributing to the enhancement of the antipoisoning ability. More importantly, the coatings do not hurt the oxygen reduction reaction (ORR) activity of commercial Pt/C, which exhibits a half wave potential of 0.84 V in an acidic electrolyte. The spectroscopic and theoretical results confirmed that the coatings originate from a strong Pt bonding to pyridinic N of N-doped graphene and that the high ORR activity results from the coordinately unsaturated carbon atoms, as the real ORR active sites, to strongly capture electrons from Pt.

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