Preparation and characterizations of the catalystPrevious experiments already evidenced the salt-templating effect of NaCl for the preparation of NPCs31,32,33 and carbon nitrides34,35. The presence of salt reduces the volatility of organic intermediates during the carbonization and stimulates optimization of local structure by improving bond exchange, both driving higher mass yields. It is however noticed that when NaCl was mixed with the structurally stable ZIF-8 (space group: I-43m, cubic), the as-derived NPCs were all featureless in microtexture (Supplementary Fig. 1). Here, upon dispersing cubic ZIF-8 in aqueous NaCl solution and subsequent evaporation, we found that the cubic ZIF-8 characterized by a rhombic dodecahedra texture transforms into the monoclinic phase with elongated close-to-hexagonal plates (Supplementary Figs. 2, 3 and Supplementary Note 2). It should be noted that the cubic and monoclinic ZIF-8 show similar chemical bonding schemes in their structure, while the crystal structure undergoes symmetry changes (Fig. 1 and Supplementary Fig. 4) during contact with NaCl solution. The sample pyrolyzed at 950 °C (termed as MCC-950) features a preserved morphology of hexagonal plates, a heritage of the monoclinic ZIF-8 crystals (Supplementary Fig. 5). Different to traditional NPCs, the powder X-ray diffraction (PXRD) pattern confirms the successful preparation of a crystalline carbon hybrid phase coming with a series of sharp peaks at 4.9o, 9.8o, 14.8o, 24.8o, 29.9o, and 35o (Fig. 2a and Supplementary Table 2), which are indexed as the (003), (006), (009), (0015), (0018) and (0021) planes, similar to the structures that are found in graphite intercalation compound (graphite nitrate, PDF No.: 74-2329), respectively. This points to a very regular lamellar stacking behavior in MCC-950, with the c-direction being characterized by a large interlayer spacing(space group: R-3m, Rhombohedral)36. Note that most graphite intercalation compounds are not stable at ambient conditions due to the desorption of intercalants. In contrast, MCC-950 can well retain its intercalated structure upon exposure in air atmosphere for at least one year, as reflected by the well-preserved XRD pattern (Supplementary Fig. 6). This is due to the fact that the intercalant of MCC-950 is presumably a ZnOx or ZnNx species, as discussed in detail below. The other peaks centered within 15–20o and 25–30o in the XRD pattern (Supplementary Fig. 7) are indicative of the fine structures inside the stacking layers, which cannot be directly assigned to common Zn compounds or known carbon materials.Fig. 2: Characterizations of MCC-950.a XRD patterns of the final MCC-950 and conventional NPC. b, c SEM image (b) and the corresponding EDS mapping results (c). d SAED pattern (left panel) and invert contrast of electron diffraction pattern (right panel with marked spots from D1 to D11) of MCC-950. e, f High-resolution TEM images, and corresponding (inverse) FFT patterns (inset of f). Source data are provided as a Source Data file.Scanning electron microscope (SEM) images and corresponding energy dispersive spectroscopy (EDS) results (Fig. 2b, c) suggest a homogeneous distribution of the constituent elements (C, N, O, Zn) at the micrometer scale. The crystalline nature of MCC-950 is also unambiguously identified by the transmission electron microscope (TEM) images. Specifically, the selected-area electron diffraction (SAED) pattern reveals a typical hexagonal spot pattern (Fig. 2d and Supplementary Fig. 8), in which the distances of D7, D8 and D11 were measured to be 0.313-0.552 nm, matching well with the in-plane peaks of the XRD patterns (Supplementary Fig. 7 and Supplementary Table 2). This also indicates that the complex hexagons patterns are likely to be the result of the reflections from the chemically ordered atomic arrangements within the intercalation layers, and Zn is indeed the strongest scatterer in the system. Along with the lattice fringes observed on hexagonal plates (Fig. 2e, f), the corresponding fast Fourier transform (FFT) patterns further confirm the typical hexagonal arrangement of (probably Zn) atoms. The high-resolution TEM (HR-TEM) images in Fig. 2f and Supplementary Fig. 9a both identify the separable lattice fringes with hexagonal organization in MCC-950, which correspond to the periodicities of ~0.330 nm and ~0.360 nm, rather typical for ZnO substructures37,38. We however note that resolving the specific carbon structure of MCC-950, because of the much weaker contrasts, is still challenging. The thermal gravimetric analysis (TGA) shows a ~80 wt% residual at 1000 °C, implying the limited mass loss of the MCC-950 at high temperatures (Supplementary Fig. 10). Indeed, high order usually induces a higher thermal stability. In the HR-TEM images, we always observe that the central region of the particles shows clearly identifiable lattice fringes, while the particle structure of MCC-950 terminates with ‘amorphous’ edges (Fig. 2e). We also identified amorphous area at the edge of MCC-950, which is likely to be caused by the absence of Zn-containing species as intercalants to orderly separate the carbon layers (Supplementary Fig. 9b).Assuming a zinc-carbon intercalation compound, we performed acid (1 M HCl) leaching experiment on the samples, which resulted in a loss of ~70 wt% Zn. Here, we notice that the most intense (00 l) peaks of pristine MCC-950 vanished after leaching, while a strongest peak centered at 18o is identified in the XRD pattern of MCC-950-HCl (Supplementary Fig. 11a). This corresponds to a periodicity of 0.49 nm upon Zn removal. We again observe the separable lattice fringes with d = 0.59, 0.24 and 0.28 nm (Supplementary Figs. 11b–e) in HR-TEM images, which can be well assigned to the weak diffraction peaks centered at 15o, 37o, and 32o, respectively. We relate all these to the periodicities within the former 2D layers which as such lie in these pictures parallel to the surface. As reflected by a thorough comparison of the etched sample MCC-950-HCl (Zn: 1.5 wt% vs. 5.0 wt% in MCC-950), the origin of (00n) peaks in MCC-950 is clearly due to zinc species within a strictly layered carbon structure.The highly ordered structure along c direction and the large layer thickness in the nanometer region hints the existence of interacting charged species at the surface in each and in different layers. It is therefore speculated that the encouraging temperature stability of MCC-950 is largely sustained by zinc linkages, which also help establish the highly ordered 2D structure by residing in between the layers. While the presence of heteroatoms (N, O, and Zn) inevitably disrupts the high order of the basal plane (i.e. ab plane), it is noteworthy that a less-ordered carbon framework in the ab direction does not necessarily imply stacking disorder in the c direction.Structural evolution during the pyrolysis processTo elucidate the structural evolution during the pyrolysis process, the precursor was thermally treated at different temperatures. In detail, the monoclinic ZIF-8 partially transforms into zinc oxide (ZnO) at 450 °C, accompanied by the morphological change which turns from hexagonal plates into shapeless aggregates (Fig. 3a and Supplementary Figs. 12a, b). Electron Paramagnetic Resonance (EPR) spectra (Supplementary Fig. 12c) with a g value centered at 1.967 correspond to the oxygen defects of ZnO at 450 °C. Such a phase transformation appears to be completed at 600 °C, along with the regeneration of ordered hexagonal plates. Further elevating the temperature to 800 °C leads to the formation of zinc cyanide (Zn (CN)2, Supplementary Fig. 13), with the preservation of plate-like microtexture. This transformation implies that zinc is more likely to coordinate with N and/or O, residing within the interlayers of the carbon structure to immobilize the MCC-950 framework. The combined effects can explain the relatively high crystallinity and long-range order of MCC-950, even it comes with high doping levels of heteroatoms (Supplementary Table 3). Note that all the diffraction peaks of MCC-950 disappear at a higher temperature of 1100 °C, indicating the collapse of the long-range ordered nanostructure at this final point. At this stage, we see additionally a thermal exfoliation effect, as the microstructure is characterized by thin-layer components. The substantial loss of Zn (decreased to 0.27 wt%) is assumed to be the primary reason for the structural collapse at 1100 °C (Fig. 3a and Supplementary Table 3). As clearly shown in Fig. 3b, the specific surface area (SBET) of these samples increases monotonously with elevated carbonization temperature, except for the case in MCC-950 (890 m2 g−1), which falls between that of 800 °C (1063 m2 g−1) and 1100 °C (2665 m2 g−1) samples, indicating potential variation of the interlayer porosity held by zinc-containing species. The high SBET value of the 1100 °C sample points to the formation of more defects and micropores. The pore size distribution of these samples highly resembles each other, albeit with substantially different crystal structure and SBET (Fig. 3c). Specifically, they feature a bimodal distribution of micropores (1.2 nm) and mesopores (2.4 nm), whose volumes scale with carbonization temperature and reach the highest value at 1100 °C. The combined findings are unambiguously indicative of the formation of a highly ordered packing structure of MCC-950 with internal pores in the layers, which is seemingly supported by a suitable dosage of Zn.Fig. 3: Formation process of the samples pyrolyzed at different temperatures (T).T = 450 °C, 600 °C, 800 °C, 950 °C, 1100 °C. a XRD patterns. b Nitrogen sorption isotherms, SBET represents the specific surface area. c Pore size distributions. d–f The C 1s (d) N 1s (e) and O 1s (f) XPS spectra with deconvoluted peaks. Source data are provided as a Source Data file.X-ray photoelectron spectroscopy (XPS) analyses confirm the presence of different nonmetal sites in MCCs, as shown in Fig. 3d–f and Supplementary Fig. 14. The deconvoluted C 1s XPS spectra of the 600 °C and 800 °C samples comprise four major peaks centered at 284.8, 286.0, 287.4, and 288.6 eV, corresponding to C = C, C–O (or C ≡ N), C = O, O–C = O (or N–C = N), respectively39,40. The new π–π shake-up satellite peak in higher-temperature (950 °C and 1100 °C) pyrolyzed carbons centers at ~290.6 eV (Fig. 3d)41, pointing to the existence of conjugated or aromatic systems. The two major peaks in the deconvoluted N 1s XPS spectrum of the 600 °C sample are centered at 398.6 and 400.2 eV, corresponding to pyridinic (C = N–C) and pyrrolic N (C–NH)42, respectively (Fig. 3e). A new peak at around 399.9 eV is assigned to C ≡ N in 800 °C sample, which is related to the formation of Zn (CN)2 and partly overlaps with that of pyrrolic N43. A comparison of the 800 °C and 950 °C samples hints that Zn primarily coordinates with pyrrolic N, as indicated by its binding energy shift of ~0.3 eV and based on the fact that Zn (CN)2 is decomposed at 950 °C44. Zn removal at 1100 °C leaves the pyrrolic N more easily identifiable. It is also evident that higher pyrolysis temperature contributed to a higher proportion of graphitic N at 401.2 eV, along with the formation of oxidized N at 1100 °C. For the oxygen species, the O 1s XPS spectra of the 800 °C, 950 °C and 1100 °C samples give three similar signals centered at around 531.2 eV, 532.2 eV, and 533.3 eV, corresponding to C = O, O–C = O and C–O functional groups45, respectively (Fig. 3f). The peaks centered at around 531.0 eV and 531.7 eV in lower-temperature-pyrolyzed (600 °C) sample are related to the oxygen species (Zn-Ox and lattice O) in ZnO, which are consistent with XRD and EPR results.The Zn K-edge X-ray absorption near-edge structure (XANES) spectra in Supplementary Fig. 15a indicate that the absorption edge position of MCC-950 situated in close proximity to that of ZnO and zinc phthalocyanine (ZnPc), the valence state of Zn in MCC-950 was accordingly estimated to be +2, keeping in line with the XPS results. The Fourier transform (FT) extended X-ray absorption fine structure (EXAFS) spectrum for MCC-950 (Supplementary Fig. 15b) signifies the atomic dispersion of Zn atoms due to the absence of Zn-Zn bond (2.28 Å)46. Instead, a distinct peak assigned to Zn-N or Zn-O (1.5 Å)46 scattering path was identified, compelling evidence to validate the coordination of Zn with N or O in the sample (Supplementary Fig. 15c and Supplementary Table 4). The chemical environments of non-metallic elements (C, N, and O) were further investigated by the near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. As shown in the C K-edge NEXAFS spectrum of MCC-950 (Supplementary Fig. 16a), the peaks at 285.5, 286.8, and 287.5 eV are assigned to π* (C = C), π* (C–OH or C–O–C) and π* (N–C = N or C = O) resonances, respectively47; while the broad peak centered within 290–295 eV originates from σ* (C-N) resonance47,48. This indicates the dominance of sp2-hybridized conjugated carbon-based framework coupled with the formation of functional groups enabled by heteroatom (C and N) doping. In the N K-edge NEXFAS spectrum, the peaks at 399.8, 401.3 and 407.7 eV may originate from π* (pyridinic N), π* (pyrrolic N) and σ* (C-N) resonances48,49, respectively. The characteristic peak assigned to metal-pyridinic N bonding generally locates between that of pyridinic N and pyrrolic N49,50, which is however not identified in our case (Supplementary Fig. 16b). The observed asymmetrical peak at 401.3 eV may overlap with that of Zn-pyrrolic (not deconvoluted here), which is also supported by the binding energy shift of pyrrolic N in the XPS N 1 s spectrum of MCC-950 when compared with other samples (Fig. 3e). The O K-edge spectrum shows a set of peaks at 530-535, 540.4 and 542-545 eV, which are indicative of π* (C–O–C or O–C = O), σ* (C-O) and σ* (C = O) resonances, respectively (Supplementary Fig. 16c)47,51. These results keep good consistency with XPS analyses, which adds further information of the local coordination structure of the involved elements in MCC-950, again corroborating that the highly crystalline sp2-hybridized carbon network is characterized by high doping levels of heteroatoms N and O. In 600 °C sample, the bands shown in the Raman spectrum are not readily assigned to the typical D and G bands that are otherwise found in NPCs (Supplementary Fig. 17) with high graphitization degree. The collected information implies a higher oxidized or more general electron-poor state in MCC-950 framework, which is beneficial for the interaction between electron-rich substrates and the specific surface of MCC-950 during the later catalytic process.Catalytic performance and identification of reactive oxygen species in Fenton-like reactionAlleviating the escalating complexity of water contaminants by new techniques is pivotal to afford accessible water resources. In this regard, Fenton-like reaction enabled by highly efficient catalysts lies at the frontier to degrade refractory pollutants, which are less likely to be removed by conventional biological treatment methods. Unlike the first- and second-generation amorphous NPCs, the MCC-950 with long-range ordered structure may come with improved electronic properties to kinetically favor chemical reactions. On the other hand, the high doping level of heteroatoms (14.2 wt% N and 9.6 wt% O in our case), which survived the high carbonization temperature, find their use in the construction of active sites within the carbon framework. Bearing these facts in mind (Supplementary Note 3), we use MCC-950 as a heterogeneous catalyst in Fenton-like reaction by the advanced oxidation process. The Fenton-like catalytic activity of MCC-950 was systematically evaluated in the degradation experiments of a broader range of pollutants (Fig. 4a, and Supplementary Table 5) upon peroxymonosulfate (PMS) activation. The dyes (methylene blue, Rhodamine B and acid orange 7) as typical chromatic pollutants from three different chemical classes, but could all be completely removed within around 5 s. Also, a 100% removal efficiency of the four phenolic compounds (phenol, bisphenol A, p-nitrophenol and 4-hydroxybenzoic acid) and two inert antibiotics (ciprofloxacin and tetracycline) were achieved within around 90 s. This comparably faster kinetics in degradation experiments (Supplementary Fig. 18) entitled MCC-950 to be one of the best catalysts for pollutant removal from water (Fig. 4b and Supplementary Table 6). Given the presence of zinc in MCC-950, we compared this work with existing single-atom zinc catalysts and comprehensively excluded its role as a potential active site in terms of catalytic activity and mechanism (Supplementary Note 4 and Supplementary Figs. 19, 20). Traditional NPCs measured as a reference show a significantly poorer ability to adsorb and degrade the pollutant (Supplementary Fig. 21). Following a 2-min degradation period, we evaluated the total organic carbon removal rate by analyzing the liquid sample separated from catalyst powder. The results, as depicted in Supplementary Fig. 22, illustrate that our system demonstrates exceptional mineralization capability, with 44-64% of organic carbon being effectively removed in just 2 min of treatment.Fig. 4: Fenton-like catalytic performances of MCC-950.a Degradation profiles of MCC-950 towards dyes (I), phenol derivatives (II) and antibiotics (III) upon PMS activation. MB: methylene blue, RhB: Rhodamine B, AO7: acid orange 7, PE: phenol, BPA: bisphenol A, PNP: p-nitrophenol, HBAc: 4-hydroxybenzoic acid. b A comparison of the catalytic degradation performance with recently reported cases. c Zeta potentials of MCC-950 and the acid-etched sample MCC-950-HCl. The shadowed regions (light gray color) in (a–c) denote the adsorption period (30 min) prior to catalytic reaction. d Comparison of quenching kinetics of MCC-950 under different conditions. e EPR spectra for PMS activation using different probing agents. f In situ Raman spectra of MCC-950/PMS system. Inset: the binding and conversion processes of PMS molecules on the catalyst surface. g Current response of MCC-950 upon changing the injection sequences of PMS and PNP. h Proposed PMS activation mechanism at the interfaces of MCC-950, which is adsorbed and then transforms into metastable intermediate PMS*, followed by decomposition and the selective generation of 1O2. Reaction condition: [pollutants] = 20 mg L−1, [PMS] = 0.4 g L−1, [catalyst] = 0.08 g L−1, T = 298 K, initial solution pH = 6.5. Error bars in (a, c, d) represent the standard deviations of three independent measurements. Source data are provided as a Source Data file.We further found that the zeta potentials of all samples in H2O (Fig. 4c) were positive, while MCC-950-HCl possessed rather negative zeta potential after acid leaching, suggesting the removal of Zn cations from the surface and between the layers leaves the carbon framework negatively charged. The macro-cationic yet electron-poor MCC-950 allows extra interaction with foreign substrates to afford high catalytic performance.The control experiments of the sole addition of PMS alone, MCC-950 alone, and Zn2+ alone do not substantially decompose pollutant (Supplementary Fig. 23a). It is noteworthy that the higher surface area of the sample carbonized at 1100 °C does not contribute to a superior catalytic performance, as evidenced by its similar degradation profile with that of MCC-950 (Supplementary Fig. 23b). This is emphasized as it implies the relevant catalytic performance is bound to the crystalline nanostructure in MCC-950, relative to the already disordered nature of the sample at 1100 °C. The practically relevant catalytic performance of MCC-950 is further assessed by probing the RhB, CIP, and TC degradation kinetics in manually configured solutions (Supplementary Figs. 23c–f and Supplementary Figs. 24, 25) with different pH and interfering substances. Specifically, anions (Cl−, NO3− and HPO4−), cations (Na+, Zn2+, Mg2+, and Ca2+), hardness, and the presence of humic acid (as a soil model) did not significantly influence the degradation rate of these pollutants. These experimental outputs show that the catalytic degradation initiated by MCC-950 is universally applicable and less likely to be intercepted by common organic and inorganic substances in water. We additionally monitored the corresponding zinc ion leaching after using MCC-950 for activation reaction under different initial pH conditions. The results, as illustrated in Supplementary Figs. 26, demonstrate that MCC exhibits minimal zinc ion leakage across a broad pH spectrum, ranging from pH 1 to 9. Importantly, these levels remain well below the WHO-established safe reference value of 3 ppm52. The cycling tests further verify the encouraging stability of MCC-950 (Supplementary Fig. 27).To identify the possible reaction pathways in MCC-950/PMS system, quenching experiments were performed (Fig. 4d). Clearly, methanol and t-butyl alcohol exerted limited impacts on RhB degradation, while furfuryl alcohol and NaN3 completely quenched the reaction, suggesting that singlet oxygen (1O2) is a relevant reactive oxygen species (ROS) upon PMS activation. EPR experiments were further conducted to identify the ROS in MCC-950/PMS system (Fig. 4e). By using DMPO (5,5-dimethyl-1-pyrroline N-oxide, dissolved in H2O) as probing agent, we observed typical septet signals that are assigned to DMPOX (5,5-dimethyl-1-pyrrolidone-n-oxyl), which serves as a product of the non-radical pathways in PMS activation (Supplementary Fig. 28)53,54,55. This is further backed by using MeOH as solvent, which can capture superoxide radicals (O2•−) signals if they are produced. However, we found that the DMPOX signals remain unchanged, underlining the non-radical pathways to be dominant in MeOH solvent. When TEMP (2,2,6,6-tetramethylpiperidine) was used, the triplet peaks of TEMP-1O2 were clearly detected in the EPR spectrum. We further conducted solvent exchange experiments, replacing the solvent H2O with D2O (Supplementary Fig. 29). When D2O was used as the solvent, we observed a clear enhancement in the degradation kinetics of the MCC-950/PMS/Pollutant system, thereby confirming 1O2 as dominant ROS in the system. Next, in situ Raman spectra were recorded to reveal the surface chemical evolution in MCC-950/PMS (Fig. 4f). A dominant peak centered at ~980 cm−1, which is assigned to SO42−, gradually emerged with prolonged reaction time. The species located at ~930 cm−1 is primarily ascribed to the formation of peroxo species bonded to the surface sites, and their stretching vibrations. The intermediate species (HSO5−) centered at ~1050 cm−1 gradually disappears56, along with the appearance of a new peak at 1075 cm−1, which implies the transformation from HSO5− to HSO4− 57. The transformation from HSO5− to SO42− and HSO4− indicates the hydrogen transfer process which finally generates 1O2. The above results collectively suggest that MCC-950 can efficiently activate PMS for improved advanced oxidation processes.Catalytic mechanismChronoamperometry measurements were performed to monitor the surface-activated intermediates and electron flow during PMS activation. The injection of PMS gave rise to distinct current drop and the largest current gap was detected in MCC-950 (Fig. 4g and Supplementary Figs. 30a, b), which signifies the promoted electron transfer in the highly crystalline carbon. Clearly, there were two stages of current changes after adding PMS. The first stage came with rather steep tendency and points to the fact that the adsorbed PMS can rapidly assign electrons to the electron-poor MCC-950 with long-range ordered structure, accompanied by the transformation from PMS to its metastable intermediate PMS* with accepting electrons (current drop). The activation reaction on the catalyst surface becomes sluggish due to the significant occupation of active sites and constraints in mass transfer within the solution (current rebound). Benefiting from the high doping amounts of the heteroatoms N and O with lone-pair electrons, PMS* is readily activated by Lewis-base sites to decompose quickly. Following the consumption of PMS* at the first stage, the adsorption sites in MCC-950 are regenerated to further capture PMS, albeit slower in the second stage, indicating that the catalyst is still loaded with electrons. Among the four phenol derivatives as pollutants, PNP shows the poorest electron-donating ability. Therefore, we used PNP as a comparably inert probe to evaluate the efficiency of deep oxidation. The injection of PNP again resulted in a current drop and indicates the electron transfer from PNP to PMS*, while the decomposition of PMS* explains the current rebound. During this process, the activated pollutant was subjected to an advanced oxidation process for catalytic degradation. Note that when PNP was added at first, no current response was observed, which implies the absence of electron transfer from PNP to catalyst surface and highlights the importance of PMS activation for pollutant degradation. This process was further evidenced by a noticeable change of current in the linear sweep voltammetry curve of MCC-950/PMS (Supplementary Fig. 30c), which reflects the electron transfer from the catalyst to the adsorbed PMS. We further evaluated the consumption of PMS with or without the pollutant, and the results showed that the introduction of pollutant increased the utilization rate of PMS (Supplementary Fig. 31) from 46% to 60%. This can be directly related to the effective electron transfer to the targets which then consumes the surface-adsorbed PMS.It was previously discussed that the stoichiometry between surface-activated PMS and pollutants could be related to the origin of catalytic activity for N- and O-doped carbon materials58,59. In general, lower carbonization temperature contributed to more rapid stoichiometry-dependent reaction at a constant electron transfer rate, while higher temperatures gave fewer binding sites, which is fortunately compensated by higher kinetics and catalytic performance. As discussed above, the well-preserved atomic arrangement of MCC-950 enables not only a very high density of active sites, but also the necessary high-speed electron transfer. The electron-deficient, heteroatom-doped carbon effectively promotes the primary activation of negative PMS, which then enables a nucleophilic attack onto the elongated S-O bond to form an activated PMS* with dramatically improved oxidative capability. As intermediate species, surface-confined PMS* might oxidize the pollutants at the interface of MCC, or it generates interfacial 1O2 (Fig. 4h). Combined with the carbon network around active centers and the nanoscopic 2D layered structure of MCC-950, the electron transfer from pollutants is not limited to the close proximity of the surface-adsorbed PMS itself, but the total carbon surface.In summary, we conclude that interfacial 1O2 and surface-activated PMS are the main oxidative species for the degradation of pollutants that occur on the interfaces of the catalyst. The electron-deficient MCC modulated by N- and O-doping in carbon frameworks promote the primary adsorption of PMS, while electron transfer as the second contribution to binding gives surface-activated oxidative PMS species, and this activation process is highly promoted by the rapid transfer of electrons and efficient electron delocalization due to the highly crystalline nanostructure around active centers (Fig. 4h). All these well explain the fast dynamics of MCC-950 compared with other types of catalysts.
