MnFe₂O₄ Nanocrystals Wrapped in a Porous Organic Polymer: A Designed Architecture for Water‐Splitting Photocatalysis

Abstract

A novel MnFe O -porous organic polymer (POP) nanocomposite was synthesized by a facile hydrothermal method and using the highly cross-linked N-rich benzene-benzylamine POP. The nanocomposite presented highly efficient photocatalytic performance in the hydrogen evolution reaction (HER) from pure water without addition of any sacrificial agent under one AM 1.5 G sunlight illumination. A photocatalytic activity of 6.12 mmol h g was achieved in the absence of any noble metal cocatalyst, which is the highest H production rate reported for nonprecious metal catalysts. The photocatalytic performance of MnFe O -POP could be attributed to the intrinsic synergistic effects of manganese ferrite (MnFe O ) nanoclusters interacting with the nitrogen dopant POP with a unique mesoporous nanoarchitecture and spatially confined growth of MnFe O in the interconnected POP network, leading to high visible-light absorption with fast electron transport.

The Design of a New Cobalt Sulfide Nanoparticle Implanted Porous Organic Polymer Nanohybrid as a Smart and Durable Water‐Splitting Photoelectrocatalyst

“…[41] The high-resolution N1sX PS peak appearing at 398.9 eV could be assigned to the presence of the mono-functional symmetrical nitrogen group on POP surface, supplying additional evidence for the formation of aC o-N x bond which is beneficial in improving electrocatalytic activity (Figure 6f). [42][43][44][45] The onset overpotential of the photocurrent of CoS x @POP film is approximately 92 mV versus RHE.T he photocurrentd ensity of the pristine Co 3 O 4 and CoS x is not high with the value of ca.À1.5 andÀ2.5 mA cm À2 at 0Vversus RHE, whichi sq uite similar to each other in terms of over potential. Similarly,t he positive displacement in the binding energies in the N1Ss pectrum of CoS x @POP compared with the bare POP demonstrated the interaction between the N-rich POP and cobalt sulfide nanoparticles which builds a" bridge"f or the charge transfer between POP and Co 9 S 8 (Figure 6f).…”

“…All the photocurrents exhibited ar eductive photocurrent, which is attributed to the PEC water reduction. [42][43][44][45] The onset overpotential of the photocurrent of CoS x @POP film is approximately 92 mV versus RHE.T he photocurrentd ensity of the pristine Co 3 O 4 and CoS x is not high with the value of ca.À1.5 andÀ2.5 mA cm À2 at 0Vversus RHE, whichi sq uite similar to each other in terms of over potential. However, after grafting on the surface of the POP,t he biphasic composite system showed enhanced current density with lowering of the over potential to 0.18 and 0.25 Vf or Co 3 O 4 @POP and CoS x @POP respectively.…”

MOF‐Derived Bifunctional Iron Oxide and Iron Phosphide Nanoarchitecture Photoelectrode for Neutral Water Splitting

“…[13] To address this issue, extensive research is being carried out on non-precious HER catalysts, such as MoS 2 , [14,15] WS 2 , [16][17][18] CoS, [19][20][21] Mo 2 C, [22][23][24] NiMoN x , [25] Co 0.6 Mo 1.4 N 2 , [26] CoSe 2 , [27,28] MnFe 2 O 4 @POP, [29] etc., although the stability and tunability of the electron affinity remains a challenging issue for this class of compounds. However, any direct application in water-splitting devices is hindered by the high cost and scarce reserves of noble metals.…”

Photoelectrochemical Catalysis toward Selective Anaerobic Oxidation of Alcohols

“…[6,7] Recently,p hoto-induced electron-holep airs have emerged as one of the most promising approaches for photoconversiont echnologiesb yu tilizing solar energy in the environment and energy fields. For instance, photocatalytic reactions based on semiconductorsa re widely investigated in water splitting, [8][9][10][11] environmental remediation, [12][13][14][15] and CO 2 transformation to fuel. [16][17][18] Remarkably,a lthough af ew exam-ples have been successively developed (e.g.,selective photocatalytico xidation of toluene or aromatic alcohols), [19][20][21][22][23][24][25][26] photocatalysis-based organic synthesis demonstrates al arge potential for green synthesis.…”