HCl Etching Research Articles

Sn Penetrated Zincophilic Interface Design in Porous Zn Substrate for High Performance Zn-Ion Battery.

Rechargeable zinc-ion batteries are considered an ideal energy storage system due to their low cost and nonflammable aqueous electrolyte. However, dendrite growth, hydrogen evolution reaction, and self-corrosion of zinc anode brought about serious safety risks including short circuits and electrode expansion. Therefore, a modified host-design strategy with a 3D porous structure and bulk-phase penetrated zincophilic interface is proposed to boost the stability and lifetime of the Zn anode. The porous Zn substrate is constructed by universal HCl etching and the uniform and tight Sn-penetrated zincophilic interface is formed by effective electron beam evaporation (EBE). The porous substrate can uniform zinc ion flux and the Sn coating could effectively improve zinc ion deposition behavior, thus inhibiting the risk of dendrites growth and side reaction. As a result, the 3D Zn substrate with Sn interface (3D Zn@Sn) exhibits prolonged galvanostatic cycling performance up to 4500h with a low polarization of ≈25mV (1mAcm-2, 1mAhcm-2) in the symmetric cell. The full cell assembled with KVOH@Ti could maintain a high specific capacity of 148.6mAhg-1 after 500 galvanostatic cycles (10Ag-1). This work proposed an improved electrode design to realize the high performance of zinc ion batteries.

Significantly enhanced electrochemical performance of Al-Ti3C2Tx MXene synthesized from Al-Ti3AlC2 MAX phase

MXenes, a type of two-dimensional nanomaterials consisting of transition metal carbides/nitrides, have emerged as promising electrode materials for supercapacitors. Especially, Ti3C2Tx MXene prepared from Ti3AlC2 MAX phase shows great application potential in flexible supercapacitors due to its facile synthesis, excellent conductivity and film-forming property. In contrast to conventional Ti3AlC2, excessive aluminum is incorporated in the synthesis process to produce Al-Ti3AlC2. In this study, Ti3AlC2 and Al-Ti3AlC2 MAX phases are used to synthesize Ti3C2Tx and Al-Ti3C2Tx MXenes, respectively, by the same method of HF:HCl etching and LiCl intercalation. The freestanding Ti3C2Tx and Al-Ti3C2Tx film electrode is separately prepared through simple vacuum filtration. The presence of excess aluminum during the Al-Ti3AlC2 synthesis facilitates to form more homogeneous grains structure with relatively larger particle sizes and an improved stoichiometric MAX phase with a Ti:C ratio closer to 3:2. The resulting Al-Ti3C2Tx nanosheets show improved oxidation resistance with relatively uniform and larger dimensions, which facilitate the higher conductivity with slightly increased interlayer spacing for the Al-Ti3C2Tx film. Therefore, the Al-Ti3C2Tx film electrode shows more efficient ions transport and charge transfer, and thus achieves significantly enhanced capacitance (399 F g−1 at 1 A g−1) and rate performance (63.6 % retention from 1 to 10 A g−1) compared to the Ti3C2Tx film electrode (342 F g−1 at 1 A g−1, 55.6 % retention from 1 to 10 A g−1). Moreover, the Al-Ti3C2Tx-based flexible sandwiched supercapacitor also exhibits superior energy storage performance. The impressive results indicate that Al-Ti3C2Tx MXene synthesized from Al-Ti3AlC2 MAX phase possesses the great application potential in flexible supercapacitors.

An Assessment of the Lateral Selective Etching, with HCl, of High Versus Low Ge Content SiGe Layers

We have evaluated the feasibility of selectively etching, with gaseous HCl, high versus low Ge content SiGe layers. To that end, we have grown {20 to 25 nm thick Si / ~ 12-15 nm thick Si0.8Ge0.2 or Si0.75Ge0.25 / ~ 11-14 nm thick Si0.5Ge0.5} multilayers on SOI substrates. After a low temperature capping with SiN, such stacks were patterned into regular arrays of square mesas or lines with a stop on the buried oxide, to laterally etch the layers of interest. We first determined, at 500°C, 600 Torr, the (001) blanket HCl etch rates of SiGe 30% and 40%: 1.4 and 5.3 nm min.-1. We then switched over to patterned wafers. The lateral selective etching of Si0.5Ge0.5 versus Si0.8Ge0.2 (and Si) was feasible and the following features highlighted: (i) Si0.5Ge0.5 lateral etch rates along the <110> directions were much smaller than in the vertical [001] direction and (ii) because of micro-loading, lateral etch rates were definitely higher for squares than for lines (0.9-1.1 nm min.-1 for lines, to be compared with 1.7–2.1 nm min.-1 for squares). Meanwhile, the lateral selective etching of Si0.5Ge0.5 versus Si0.75Ge0.25 was far from being perfect, with much higher Si0.5Ge0.5 etch rates and a significant Si0.75Ge0.25 recessing at tunnel entrances. Si0.75Ge0.25 floors and ceilings were otherwise far more etched and thus tilted than Si0.8Ge0.2 ones. Inserting very thin Si spacers between Si0.5Ge0.5 cores and Si0.75Ge0.25 claddings partly solved those issues, with no recessing and lesser etchings at the entry points of tunnels.

Effect of precursor morphology on the electrochemical performance of porous Si anodes prepared by magnesiothermic reduction

The magnesiothermic reduction of SiO2 to Si is a promising route for preparing high-energy-density Si-based anode materials for lithium-ion batteries. However, the effect of the initial morphological properties of SiO2 on the electrochemical performance of Si remains unclear. Herein, porous Si (PSi) particles were prepared from four different SiO2 precursors, namely, spherical SiO2 particles with diameters of 0.3 and 20 μm (denoted SiO2-0.3 and SiO2-20, respectively), fumed SiO2 powder (denoted SiO2-F), and well-ordered mesoporous SiO2 particles (denoted SiO2-K). Highly crystalline PSi particles were obtained after magnesiothermic reduction and subsequent HCl and HF etching. PSi prepared from SiO2-0.3 maintained its precursor morphology to some extent, whereas highly irregular Si particles were produced from SiO2-20, SiO2-F, and SiO2-K. Among the PSi particles, those prepared from SiO2-0.3 delivered the highest reversible capacity (1427 mAh g–1 at 0.1 A g–1) after 50 discharge–charge cycles. Because of the unique hierarchically porous morphology of PSi prepared from SiO2-0.3, the expansion of its electrode thickness was suppressed below 140 %. Moreover, owing to its nanosized Si domains and good electrode wetting, PSi prepared from SiO2-0.3 demonstrated improved electrochemical properties compared with those prepared from SiO2-F and SiO2-K.

Digital etching of AlGaN/GaN heterostructures with GaN cap using inductively coupled oxygen plasma process combined with wet chemical treatment

In this work, AlGaN with a GaN cap has been etched in a cyclical process with ICP-RIE O2 plasma oxidation and wet etching in dilute HCl. The oxygen plasma ICP-RIE etching of the AlGaN at an ICP plasma power of 200 W and radio frequency bias power of 100 W led to an etch depth of ∼1.5 nm per digital cycle with increased surface roughness. The AlGaN remained unaffected by the wet etching process alone without any ICP-RIE O2 plasma oxidation, maintaining a surface roughness similar to that of the substrate. AlGaN was etched to a depth of ∼12 nm after six cycles of digital etching with an etch rate of 1.9–2.1 nm/cycle showing an improved surface roughness. The XPS analysis at each stage of the etching process reveals that the O2 plasma oxidation initially oxidizes the GaN cap and the AlGaN layer and is later effectively removed by the HCl solution. The digital etching method has proven effective in controlling etch depth and surface roughness, which are needed to fabricate AlGaN high electron mobility transistors.

Mesoporous hollow Fe4[Fe(CN)6)]3 hierarchical nanocrystal architecture for advanced sodium-ion batteries

Prussian blue (PB) has been broadly recognized as promising cathode materials for sodium-ion batteries (SIBs) due to its large interstitial space and robust frame structure, whereas their applications are impeded by unsatisfied long-term cyclability and poor rate capability due to its inherent lattice defects. Herein, we report to fabricate the mesoporous hollow Fe4(Fe(CN)6)3 (one kind of PB) hierarchical nanocrystal architecture by the hydrothermal crystallization and HCl etching of the mesoporous precursor Fe4[Fe(CN)6]3 cubic particles, leading to high crystallinity and large specific surface area. The resultant Fe4[Fe(CN)6]3 cathode for SIBs exhibits a good reversibility and cycling stability with a capacity retention of 75.6 % at 0.5 C after 200 cycles as well as superb rate capability featuring a stable discharge specific capacity of 30.2 mAh g−1 at as high as 10 C, demonstrating the fast kinetics and low polarization of electrochemical reaction, which might be ascribed to the unique architecture and high crystallinity. This offers a new route to designing PB cathode of for SIBs with high rate capabilities.

Investigating the impact of silane on different surface modified stainless steel ultra-thin strips and the bonding interface of stainless-steel bonded with epoxy

The silane coupling agent is extensively utilized to improve the bonding strength between the stainless steel (SS) ultra-thin strip and the epoxy resin. Along these lines, the response of SS strips with different mild surface modifications to silane coupling agent was systematically investigated. It was found that the HCl etching and anodizing-thermally treating sample (EAT-SS) exhibited a relatively optimal response to the KH550 silane coupling agent. This effect was attributed to the increased surface roughness and abundant micro/nano scale porous structure. The shear strength of the EAT-SS/epoxy specimen increased from 6.05 MPa to 16.04 MPa due to the improved interlock effect induced by the coexistence of the micro and nano structures, further increased to 20.36 MPa after the incorporation of the KH550 coating with a 4 wt% mass fraction. This improvement can be attributed to the increased thickness of the bonding interface and dual introduction of mechanical interlocking and chemical bonding effects after the application of the KH550 coating. Besides, the enhancement effect of the KH550 coating was stronger than that of KH560, which can be ascribed to the chemical reaction between the amino group in the former and the epoxy group in epoxy resin.

Reducing the SiOx layer on Si/reduced graphene oxide enables fast and reversible lithium-ion storage capability for lithium-ion batteries

To investigate whether the presence of a SiOx layer affects the electrochemical performance of silicon-based materials, particularly the silicon-carbon anode material, a facile and scalable process involving HCl etching, annealing, and HF etching was employed to synthesize a silicon-carbon composite (Si/SiOx-rGO) and reduce the SiOx layer content at the silicon-carbon interface to obtain a Si-rGO composite. Experimental results demonstrate that this method effectively reduces the SiOx content in the composite. By decreasing the SiOx layer content, the Si-rGO composite exhibits the specific capacities of 758.3 mAh g−1 at 3 A g−1 and 557 mAh g−1 at 5 A g−1. After 200 cycles at 2 A g−1, it still retains a capacity of 930.8 mAh g−1. These findings offer comprehensive insights into the SiOx layer at the silicon-carbon interface, thereby enhancing the application of silicon-based anode materials.

Molten salt N-modified Mo2CTx as a non-precious metal catalyst for efficient hydrogen evolution reaction

The two-dimensional molybdenum carbide (Mo2CTx) has a similar electronic structure to platinum, which has the potential to be one of non-precious metals catalysts for hydrogen evolution reaction (HER). However, the preparation of Mo2CTx by conventional HF and LiF–HCl etching method inevitably introduces the –F and –Cl terminations on the surface, which adversely affect activity and stability. In this study, the LiCl–KCl–Li3N molten salt was used to treat Mo2CTx at 600 °C and atmospheric pressure and introduce nitrogen heteroatoms. After treated in LiCl–KCl–Li3N molten salt, the HER performance of nitrogen-doped Mo2CTx is improved compared with that of un-doped Mo2CTx, which should be attributed to the optimization of the electronic structure of N–Mo2CTx and lower hydrogen adsorption energy barrier. This simple molten salt method provides a way to modify non-precious metal HER catalyst and introduce nitrogen heteroatoms.

Improved high-frequency and anti-corrosion performance of FeNi soft magnetic composites through regulating SiO2 shell growth in a dual silicon source involved route

Optimizing dense insulating shells plays a crucial role in developing high-frequency soft magnetic composites (SMCs) working in acidic and salty environments. Herein, raspberry-like and litchi-like SiO2 shells are fabricated on FeNi particles by using both 3-aminopropyl triethoxysilane (APTES) and tetraethyl orthosilicate. It is found that low dosages of APTES lead to raspberry-like shells consisting of internal SiO2 layer and attached SiO2 particles. While high dosages of APTES result in litchi-like shells, owing to a much higher coordinated growth rate between the inner layer and SiO2 particles. With regard to corrosion resistance performance, the litchi-like shell contributes to a more positive corrosion potential of -0.076 V, a lower corrosion current density of 2.512 × 10−6 A/cm2, a higher corrosion protection efficiency of 96.70 % and a lower ion concentration in the HCl etching solution. As for magnetic properties, higher resistivity of 1.46 × 108 Ω·m, lower eddy current loss with μ′ of 13.98 and lower tanδ of 0.01148 at 2000 kHz can be realized by the dense litchi-like shell structure. This work not only demonstrates detailed growth mechanisms of different SiO2 shells, provides FeNi SMCs with desirable high frequency and anti-corrosion performance, but also offers deeper insights into functional shell design.

Solderability of Additively Manufactured Copper Surfaces

As additive manufacturing technology for copper rapidly evolves, the likelihood for downstream joining like soldering and brazing exists. A solderability study was performed to assess process fundamentals over a variety of AM approaches. The solderability of 7 different copper (Cu) surface types were evaluated using the wetting balance technique: 4 Cu coatings (CP-007 and CP-008 conductive copper pastes, IMC-4118 conductive laser sinter paste, IMC-2501 copper ink), 2 laser processed Cu surfaces, and 1 bulk additively manufactured (AM) Cu coupon type. Laser processed surfaces were subjected to either circular or linear laser raster patterns. AM coupons were fabricated via a powder-bed laser process. In-situ force measurements were recorded while coupons were dipped into and removed from a 63Sn-37Pb (SnPb) or 96.4Sn-3.0Ag-0.6Cu (SAC305) solder bath, allowing contact angles and surface energies to be calculated. Meniscus height values were also measured. Surfaces were characterized before and after dipping via optical and electron microscopy. Results conclusively indicated that although all samples were intended to represent pure Cu, wettability was found to be strongly dependent on surface type with several samples exhibiting no wetting. Although the CP-007 paste performed the best of any non-traditional surface, all nontraditional surfaces saw signifi cant wettability improvements with aggressive cleaning via HCl etching.

Light-trapping structures fabricated in situ for ultrathin III-V solar cells

Here, we describe a fully in situ method of fabricating light-scattering structures on III-V materials that generates a rough morphology via vapor phase etching and redeposition. Fully in situ methods support higher industrial throughput by utilizing the growth reactor to generate the light-trapping structures after device growth without removal from the reactor. We use HCl and PH3 to etch and redeposit scattering morphologies on Ga0.5In0.5P in a dynamic hydride vapor phase epitaxy (D-HVPE) reactor. We show that the addition of PH3 leads to redeposition during the vapor phase HCl etching of Ga0.5In0.5P and that HCl flow rate and time exposed to HCl-PH3 each independently cause a linear increase in the redeposited feature size, indicating that redeposition proceeds by island growth in a III-Cl-limited, hydride-enhanced HVPE regime. Auger electron spectroscopy and scanning transmission electron microscopy with energy dispersive spectroscopy (STEM-EDS) reveal redeposition to be highly Ga-rich GaInP, i.e., Ga(In)P. The Ga-rich nature of the redeposition results from the higher thermodynamic driving force for Ga incorporation than for In during HVPE growth and the difference in the volatility of the III-Cl etch products. The resulting morphologies have high broadband scattering, as determined by normal specular reflectance and integrating sphere measurements, indicating effectiveness as light-scattering structures. In a 270-nm-thick GaAs photovoltaic device with a textured back surface, we achieve a 4.9% increase in short circuit current density (JSC) without any loss in open-circuit voltage (VOC) relative to a planar control using only a 60 s in situ texturing treatment.

Efficient self-cleaning and antibacterial ceramics with ultra-low doping and high exposure of silver

The secondary bacterial infection of COVID-19 is known to contribute significantly to mortality rates. Silver (Ag)-based antibacterial ceramics have emerged as a prominent solution for daily antibacterial applications, aiming to minimize the reliance on disinfectants while safeguarding human health. However, the fabrication of Ag-based antibacterial ceramics with low Ag content, high dispersion, and high exposure still faces challenges. In this work, an innovative method was proposed to doping Ag nanoparticles (Ag NPs) into glass ceramics (GC) via a "melt-freeze" method, then efficient and stable Ag-doped antibacterial ceramics (GC-xAg@BiOCl) were fabricated through facile in-situ HCl etching GC. Results indicate that the low Ag content (0.03 mol%) and high dispersion of Ag NPs are fully exposed and anchored on the surface, and constructed Schottky junction Ag/BiOCl contributed to antibacterial and photocatalytic activity. The degradation rates of norfloxacin and methylene blue by GC-0.25Ag@BiOCl can reach 71.0% and 55.3% under visible light irradiation, respectively. Moreover, The GC-0.25Ag@BiOCl exhibited significant antibacterial activity against Escherichia coli (E.coli) and Staphylococcus aureus (S. aureus), with E.coli at 7.3 log10 cfu/mL and S. aureus at 7.0 log10 cfu/mL completely inactivated under visible light irradiation. Additionally, the antibacterial mechanism and charge transfer mechanism were explored.

Polishing and etching damages of ZnO single crystals studied using time-resolved photoluminescence spectroscopy

Controlled thinning of wide bandgap semiconductors by chemo-mechanical polishing (CMP) and/or reactive ion etching (RIE) has been one of the versatile methods for various optoelectronic applications. The influences of CMP and subsequent wet chemical etching, as well as independent RIE, on the room-temperature photoluminescence lifetime for the near-band-edge emission [τPLNBE(RT)] of O-polarity c-plane ZnO single crystals were examined by using time-resolved photoluminescence measurements. τPLNBE(RT) decreased from a nanosecond range to a few picoseconds (ps) by a conventional CMP, indicating a generation of high-concentration midgap recombination centers, such as nonradiative recombination centers and deep radiative recombination centers. τPLNBE(RT) was progressively regained up to 600 ps by a subsequent etching using HCl aqueous solution. However, the recovery saturated at the etching depth of about 200 nm and τPLNBE(RT) was not restored even after etching by 350 nm. The results indicate the introduction of certain structural deformations during the CMP. Because x-ray diffraction measurement revealed the presence of incoherent surface domains right after the CMP and the HCl etching gave rise to inhomogeneously etched canyons, nonradiative recombination centers, such as dislocations and vacancy clusters, are likely generated by mechanical shear stresses. τPLNBE(RT) also decreased by the RIE. However, the degradation was less significant than the case for the CMP, because RIE scarcely gives mechanical stresses. Interestingly, τPLNBE(RT) for the samples etched under higher plasma power was longer than the lower power cases. From the results of x-ray photoelectron spectroscopy measurements, unintentionally deposited oxide films containing Si are proposed to act as an attenuating layer for the introduction of nonradiative recombination centers.

Anisotropic strain induced fracture of Ni(OH)2 nanosheet electrodes for supercapacitors through a charge-ordered mixed-valent intermediate

Beta nickel hydroxide (β-Ni(OH)2) is a popular electrode material for manufacturing Ni-H batteries and pseudocapacitors. The cycle stability of β-Ni(OH)2 electrodes is limited owing to their volumetric changes during charge–discharge process, in which, internal charge distribution of β-Ni(OH)2 changes with the external swelling. In this paper, β-Ni(OH)2 nanosheets synthesized by HCl etching have been taken as an example to investigate details of the morphology and structure variations during capacity fading of these electrodes. The findings shows that the β-Ni(OH)2 nanosheets form a wrinkled surface and become fractured after the charge–discharge cycles. Fractured nanoparticles with diameters around 10 nm could be collected by the polyaniline coating on the β-Ni(OH)2 nanosheets. Charge-ordering of Ni2+/Ni3+ has been observed in β-Ni(OH)2 nanosheet via a sluggish cyclic voltammetry cycling. Although the charge-ordering state may lower the strain penalty involved in charging-discharging, the increased anisotropic strain in the β-Ni(OH)2 finally leads to the fracture and capacity fading of the nanosheet electrodes.

Wet-chemical surface texturing of AZO substrate for improved perovskite solar cells

Aluminum-doped zinc oxide (AZO) is a promising substrate for perovskite solar cells (PSCs) because of its low cost, easy accessibility, and good conductivity. However, its relatively low transmittance with low resistance and inevitable reflectance loss makes it unfavorable for high-performance AZO-based PSCs. Herein, a simple and effective strategy that textures the surface of AZO substrate via a diluted HCl etching, is developed to boost PSC performance. The textured AZO substrate exhibits greater haze, higher transmittance, and lower reflectance for permitting more photons to reach and be absorbed within PSCs. In addition, the textured AZO substrate not only exhibits improved surface wettability that can enhance the buried interfacial contact and enable the growth of high-quality perovskite film, but also possesses reduced oxygen vacancies and lower work function (WF) that can suppress the recombination and reduce the energy barrier for electron extraction. As a result, the PSC on textured AZO substrate shows improved fill factor (FF, 70 %) and enhanced short-circuit current density (Jsc, 23.7 mA/cm2) compared with the reference cells (63 % and 21.1 mA/cm2), yielding a much-increased power conversion efficiency (PCE) from 13.9 % to 17.6 %. The present work opens the door for the employment of AZO substrate in future commercialization of PSCs.

Anisotropic non-plasma HCl gas etching of a (010) β-Ga2O3 substrate

We demonstrated the effectiveness of plasma-free HCl gas etching on a SiO2-masked (010) β-Ga2O3 substrate. The etching process proceeded anisotropically in the window areas, resulting in the fabrication of holes or trenches that were surrounded by etching-resistant (100)- and (01)-faceted sidewalls. When we etched in the striped windows along [001], we were able to create fins and trenches with flat (100)-faceted vertical sidewalls and slightly rough {310}-faceted inclined bottom corners. The vertical-to-horizontal etching ratio was as high as ∼11–14. Our findings indicate that HCl etching is a promising method for fabricating high-aspect-ratio fins/trenches on (010) substrates without causing plasma damage.

Lanthanide-doped upconversion glass–ceramic photocatalyst fabricated from fluorine-containing waste for the degradation of organic pollutants

Fluorine-containing waste is one kind of hazardous waste characteristic by hard disposal and utilization, it is an attractive way to prepare for fluoride-based luminescent matrix. In this work, to realize the high value-added utilization of fluorine-containing waste and reduce cost of the raw materials for preparation near-infrared (NIR) glass–ceramic (GC) photocatalyst, the pure fluoride of luminescent matrix was replaced by introducing fluorine-containing waste. The waste contained NIR GC photocatalyst was synthesis by the method of facile in-situ etching of an upconversion GC with HCl, which possesses core–shell structure, where the GC micro-powder including optically active centers lanthanides doped CaF2 nanocrystals are displayed as the core, and the BiOCl is as the superficial coating. The upconversion emission performance of CaF2 based luminescent matrix in photocatalyst is not weakened with HCl etching. NIR GC photocatalyst has high methyl orange and enrofloxacin degradation rate of 86 % and 82 % over 180 min after NIR light irradiation, respectively. The UV–Vis–NIR photocatalytic activity was enhanced degradation rate (93 % in 15 min) of enrofloxacin compared with those of commercial P25 and BiOCl. In addition, the photocatalyst had stable photocatalytic activity and it also can be regenerated. The study provided references for high value-added utilization fluorine-containing waste.

Effects of surface compositions and interlayer distance on electrochemical performance of Mo2CTx MXene as anode of Li-ion batteries

In this study, highly pure Mo2CTx MXene was made from Mo2Ga2C by hydrothermal method in five different etching solutions (LiF, NaF, KF, NH4F or HF). The as-prepared multi-layer MXene samples were furthered delaminated by tetrabutyl-ammonium hydroxide (TBAOH) to increase the interlayer distance. The c-lattice parameter (c-LP) was increased from 20.3 Å to 23.87 Å. Thereafter, the electrochemical properties of Mo2CTx MXene samples as anode of Li-ion batteries (LIBs) were investigated. The multilayer Mo2CTx MXene made by KF + HCl etching had some residual K+ on the surface and had higher discharge specific capacity (32.7 mA h/g at the current density of 800 mA/g) than the samples made by other etchants. This is because that the residual K+ on MXene surface pillar the multi-layer structure, which provides larger room for Li+ storage and immigration. The Mo2CTx MXene after delamination with the c-LP of 23.87 Å presented a high discharge specific capacity of 239 mA h/g at the current density of 800 mA/g, which was 7.3 times higher than the discharge specific capacity of Mo2CTx MXene before delamination. The final discharge specific capacity was 118.83 mA h/g at 2000 mA/g after 100 cycles. The superior electrochemical performance of delaminated Mo2CTx MXene was attributed to the more easily accessible ion active sites between layers and the lower resistance. Therefore, the increasing of interlayer distance is the main direction to improve the performance of Mo2CTx as anode of LIBs.

Pt Nanoparticles and NiO Nanosheets on Ni Foam for Photothermal Degradation of Toluene

The construction of highly efficient metal foam-based monolithic catalysts is essential for promoting the exploration of photothermal catalytic oxidation of volatile organic compounds (VOCs) in practical application. Herein, Pt nanoparticles and NiO nanosheets directly grown on Ni foam via the substitution and acid etching-assisted method are prepared and applied in photothermal degradation of toluene. The HCl etching can tune the concentration of oxygen vacancies of the monolithic catalyst and motivate the synergetic effect of Pt nanoparticles and NiO nanosheets. Meanwhile, the obtained monolithic catalysts have strong light absorption capacity and highly efficient conversion of light-to-heat ability. Benefiting from these, the Pt/NF-A2 sample shows the good performance toward photothermal degradation of toluene. These findings may provide insights into the design of efficient metal foam-based monolithic industrial catalysts for photothermal degradation of VOCs.