Rational design supporting material for palladium (Pd)-based catalyst can maximize its electrocatalytic performance for ethanol oxidation reaction (EOR) catalyst in alkaline condition. Utilizing the unique two-dimensional structures and outstanding physicochemical property of graphene and black phosphorus (BP), herein, we proposed and designed a black phosphorus–graphene heterostructure for supporting Pd nanoparticles. Through merely ball-milling of activated graphene (AG) and black phosphorus (BP), the AG–BP hybrid with a linkage of P–C bonding is used as supports of Pd. The obtained Pd/AG–BP hybrid exhibits ultrahigh electrochemical activity toward EOR. Remarkably, it can achieve a high mass peak current density of ∼6004.53 and ∼712.03 mA mgPd –1 before and after the durability tests of 20 000s on EOR, which are ∼7.19 and 80 times higher than those of commercial Pd/C. The experimental analysis and density-functional-theory calculation show that Pd becomes more positive with electrons transfer from Pd to AG–BP supports and is liable to absorb the OH radicals for removing COads intermediate to release active sites on EOR, together with the excellent ability to generate additional OH militants after combining with the AG–BP heterostructure.

Utilizing renewable energy to produce green hydrogen from saline water electrolysis is becoming increasingly important yet is largely challenged by the sluggish oxygen evolution reaction kinetics, the competitive anodic chlorine evolution reaction, and the resultant electrode corrosion. Here, we report an electrochemically activated Ni-Fe oxyhydroxide catalyst that delivers an early onset potential of 1.51 V at 100 mA cm −2 within mimic saline water of 0.5 M NaCl + 1 M NaOH. During the electrochemical activation, ex situ X-ray radiation and in situ Raman characterizations reveal the structural reconstruction of amorphous Ni (oxy)hydroxide generation and electronic structure modulation from Fe intercalation. Headspace gas chromatography and iodine titration results confirm the ∼100% Faradaic efficiency toward O 2 evolution on activated NiFeO x H y , whereas the long-term stability is assessed by an anion exchange membrane electrolyzer, demonstrating only 350 mV voltage decay during the 100 h continuous electrolysis at 500 mA cm −2 .

Ethanol oxidation reaction (EOR) is an important electrode reaction in ethanol fuel cells. However, there are many problems with commercial ethanol oxidation electrocatalysts today, such as poor durability, poor anti-CO poisoning ability, and low selectivity for C-C bond cleavage. Therefore, it is very meaningful to develop a high-performance EOR catalyst. Herein, we designed ternary N, S, and P-doped hollow carbon spheres (C-N,P,S) from polyphosphazene (PCCP) as Pd supports for EOR. Using SiO 2 spheres as the templates, the PCCP was first coated on the surfaces of SiO 2 spheres by in situ polymerization. Through high-temperature pyrolysis and hydrofluoric acid-etching, the hollow PCCP has a large surface area and porous structure. After loading Pd nanoparticles (NPs), the Pd/C-N, P, S catalysts with Pd NPs decorated on the surfaces of C-N, P, S can achieve a high mass peak current density of 1686 mA mg Pd −1 , which was 2.8 times greater than that of Pd/C. Meanwhile, the Pd/C-N, P, S catalyst also shows a better stability than that of Pd/C after a durability test of 3600s.

Designing high-efficiency and newly developed Pd-based bifunctional catalytic materials still faces tremendous challenges for oxygen reduction reaction (ORR) and formic acid oxidation reaction (FAO). Metallene materials with unique structural features are considered strong candidates for enhancing the catalytic performance. In this work, we synthesized copperdoped two-dimensional curved porous Pd metallene nanomaterials via a simplistic one-pot solvothermal method. The updated catalysts served as sturdy bifunctional electrocatalysts for cathodal ORR and anodic FAO. In particular, the developed PdCu metallene exhibits excellent half-wave potential (0.943 V vs RHE) and mass activity (MA) (1.227 A mg Pt −1 ) in alkaline solutions, which are 1.09 and 6.26 times higher than those of commercial Pt/C, respectively, indicating that the nanomaterials have abundant active sites, displaying surpassing catalytic performance for oxygen reduction. Furthermore, in an acidic formic acid electrolyte, PdCu metallene exhibits prominent MA with a value of 0.905 A mg Pd −1 , which is 2.76 times that of commercial Pd/C. The remarkable bifunctional catalytic performance of metallene materials can be attributed to the special structure and electronic effects. This work shows that metallene materials with curved and porous properties provide a scientific idea for the development and design of efficient and steady electrocatalysts.

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