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Electroreduction of CO2 into multi-carbon (C2+) products (e.g. C2+ alcohols) offers a promising way for CO2 utilization. Use of strong alkaline electrolytes is favorable to producing C2+ products. However, CO2 can react with hydroxide to form carbonate/bicarbonate, which results in low carbon utilization efficiency and poor stability. Using acidic electrolyte is an efficient way to solve the problems, but it is a challenge to achieve high selectivity of C2+ products. Here we report that the amine modified copper nanoparticles exhibit high selectivity of C2+ products and carbon utilization at acidic condition. The Faradaic efficiency (FE) of C2+ products reach up to 81.8% at acidic media (pH=2) with a total current density of 410 mA cm-2 over n-butylamine modified Cu. Especially the FE of C2+ alcohols is 52.6%, which is higher than those reported for CO2 electroreduction at acidic condition. In addition, the single-pass carbon efficiency towards C2+ production reach up to 60%. Detailed studies demonstrate that the amine molecule on the surface of Cu cannot only enhance the formation, adsorption and coverage of *CO, but also provide a hydrophobic environment, which result in the high selectivity of C2+ alcohols at acidic condition., (© 2024 Wiley‐VCH GmbH.)

Single-metal atomic sites and vacancies can accelerate the transfer of photogenerated electrons and enhance photocatalytic performance in photocatalysis. In this study, a series of nickel hydroxide nanoboards (Ni(OH) x NBs) with different loadings of single-atomic Ru sites (w-SA-Ru/Ni(OH) x ) were synthesized via a photoreduction strategy. In such catalysts, single-atomic Ru sites are anchored to the vacancies surrounding the pits. Notably, the SA-Ru/Ni(OH) x with 0.60 wt % Ru loading (0.60-SA-Ru/Ni(OH) x ) exhibits the highest catalytic performance (27.6 mmol g -1  h -1 ) during the photocatalytic reduction of CO 2 (CO 2 RR). Either superfluous (0.64 wt %, 18.9 mmol g -1  h -1 ; 3.35 wt %, 9.4 mmol -1  h -1 ) or scarce (0.06 wt %, 15.8 mmol g -1  h -1 ; 0.29 wt %, 21.95 mmol g -1  h -1 ; 0.58 wt %, 23.4 mmol g -1  h -1 ) of Ru sites have negative effect on its catalytic properties. Density functional theory (DFT) calculations combined with experimental results revealed that CO 2 can be adsorbed in the pits; single-atomic Ru sites can help with the conversion of as-adsorbed CO 2 and lower the energy of *COOH formation accelerating the reaction; the excessive single-atomic Ru sites occupy vacancies that retard the completion of CO 2 RR., (© 2024 Wiley-VCH GmbH.)

Developing efficient electrocatalysts for methanol oxidation reaction (MOR) is crucial in advancing the commercialization of direct methanol fuel cells (DMFCs). Herein, carbon-supported 0D/2D PtCuBi/C (0D/2D PtCuBi/C) catalysts are fabricated through a solvothermal method, followed by a partial electrochemical dealloying process to form a novel mixed-dimensional electrochemically dealloyed PtCuBi/C (0D/2D D-PtCuBi/C) catalysts. Benefiting from distinctive mixed-dimensional structure and composition, the as-obtained 0D/2D D-PtCuBi/C catalysts possess abundant accessible active sites. The introduction of Cu as a water-activating element weakens the CO ads , and oxophilic metal Bi facilitates the OH ads , thereby enhancing its tolerance to CO poisoning and promoting MOR activity. The X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure spectroscopy (XAFS) collectively reveal the electron transfer from Cu and Bi to Pt, the electron-enrichment effect induced by dealloying, and the strong interactions among Pt-M (Cu, Pt, and Bi) multi-active sites, which improve the tuning of the electronic structure and enhancement of electron transfer ability. Impressively, the optimized 0D/2D D-PtCuBi/C catalysts exhibit the superior mass activity (MA) of 17.68 A mg Pt -1 for MOR, which is 14.86 times higher than that of commercial Pt/C. This study offers a proposed strategy for Pt-based alloy catalysts, enabling their use as efficient anodic materials in fuel cell applications., (© 2023 Wiley‐VCH GmbH.)

Hetero-interface engineering has been widely employed to develop supported multicomponent catalysts for water electrolysis, but it still remains a substantial challenge for supported single atom alloys. Herein a conductive oxide MoO 2 supported Ir 1 Ni single atom alloys (Ir 1 Ni@MoO 2 SAAs) bifunctional electrocatalysts through surface segregation coupled with galvanic replacement reaction, where the Ir atoms are atomically anchored onto the surface of Ni nanoclusters via the Ir-Ni coordination accompanied with electron transfer from Ni to Ir is reported. Benefiting from the unique structure, the Ir 1 Ni@MoO 2 SAAs not only exhibit low overpotential of 48.6 mV at 10 mA cm -2 and Tafel slope of 19 mV dec -1 for hydrogen evolution reaction, but also show highly efficient alkaline water oxidation with overpotential of 280 mV at 10 mA cm -2 . Their overall water electrolysis exhibits a low cell voltage of 1.52 V at 10 mA cm -2 and excellent durability. Experiments and theoretical calculations reveal that the Ir-Ni interface effectively weakens hydrogen binding energy, and decoration of the Ir single atoms boost surface reconstruction of Ni species to enhance the coverage of intermediates (OH*) and switch the potential-determining step. It is suggested that this approach opens up a promising avenue to design efficient and durable precious metal bifunctional electrocatalysts., (© 2023 Wiley-VCH GmbH.)

Constructing electrocatalysts with p-block elements is generally considered rather challenging owing to their closed d shells. Here for the first time, we present a p-block-element bismuth-based (Bi-based) catalyst with the co-existence of single-atomic Bi sites coordinated with oxygen (O) and sulfur (S) atoms and Bi nanoclusters (Bi clu ) (collectively denoted as BiOS SA /Bi clu ) for the highly selective oxygen reduction reaction (ORR) into hydrogen peroxide (H 2 O 2 ). As a result, BiOS SA /Bi clu gives a high H 2 O 2 selectivity of 95 % in rotating ring-disk electrode, and a large current density of 36 mA cm -2 at 0.15 V vs. RHE, a considerable H 2 O 2 yield of 11.5 mg cm -2 h -1 with high H 2 O 2 Faraday efficiency of ∼90 % at 0.3 V vs. RHE and a long-term durability of ∼22 h in H-cell test. Interestingly, the experimental data on site poisoning and theoretical calculations both revealed that, for BiOS SA /Bi clu , the catalytic active sites are on the Bi clusters, which are further activated by the atomically dispersed Bi coordinated with O and S atoms. This work demonstrates a new synergistic tandem strategy for advanced p-block-element Bi catalysts featuring atomic-level catalytic sites, and the great potential of rational material design for constructing highly active electrocatalysts based on p-block metals., (© 2023 Wiley-VCH Verlag GmbH.)

In photosynthesis, solar energy is harvested by photosensitizers, and then, the excited electrons transfer via a Z-Scheme mode to enzymatic catalytic centers to trigger redox reactions. Herein, we constructed a core-shell Z-scheme heterojunction of semiconductor@single-atom catalysts (SACs). The oxygen-vacancy-rich ZnO core and single-atom Co-N 4 sites supported on nitrogen-rich carbon shell (SA-Co-CN) act as the photosensitizer and the enzyme-mimicking active centers, respectively. Driven by built-in electric field across the heterojunction, photoexcited electrons could rapidly (2 ps) transfer from the n-type ZnO core to the p-type SA-Co-CN shell, finally boosting the catalytic performance of the surface-exposed single-atom Co-N 4 sites for peroxymonosulfate (PMS) activation under light irradiation. The synergies between photocatalysis and heterogeneous Fenton-like reaction lead to phenomenally enhanced production of various reactive oxygen species for rapid degradation of various microcontaminants in water. Experimental and theoretical results validate that the interfacial coupling of SA-Co-CN with ZnO greatly facilitates PMS adsorption and activation by reducing the adsorption energy and enhancing the cascade electron transfer processes for the photo-Fenton-like reaction., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

CO 2 electroreduction is of great significance to reduce CO 2 emissions and complete the carbon cycle. However, the unavoidable carbonate formation and low CO 2 utilization efficiency in neutral or alkaline electrolytes hinder its application at commercial scale. The development of CO 2 reduction under acidic conditions provides a promising strategy, but the inhibition of the hydrogen evolution reaction is difficult. Herein, the first work to design a Ni-Cu dual atom catalyst supported on hollow nitrogen-doped carbon is reported for pH-universal CO 2 electroreduction to CO. The catalyst shows a high CO Faradaic efficiency of ≈99% in acidic, neutral, and alkaline electrolytes, and the partial current densities of CO reach 190 ± 11, 225 ± 10, and 489 ± 14 mA cm -2 , respectively. In particular, the CO 2 utilization efficiency under acidic conditions reaches 64.3%, which is twice as high as that of alkaline conditions. Detailed study indicates the existence of electronic interaction between Ni and Cu atoms. The Cu atoms push the Ni d-band center further toward the Fermi level, thereby accelerating the formation of *COOH. In addition, operando characterizations and density functional theory calculation are used to elucidate the possible reaction mechanism of CO 2 to CO under acidic and alkaline electrolytes., (© 2023 Wiley-VCH GmbH.)

The two-dimensional nanosheets are conducive to not only endow opened surfaces for loading active metal atoms but also boost the mass transfer for the heterogeneous reactions. The challenge is how to load and stabilize single-atoms on nanosheets in high-areal densities. This work reports an efficient micro-gas blasting (MGB) strategy to access versatile noble metal single-atoms/metal oxide nanosheets, including Ir 1 /CoO x , Pd 1 /CeO 2 , etc. Especially for Pt/CeO 2 nanosheets (Pt 1 /CeO 2 -S), the Pt loading is increased to 15 at%. The Pt 1 /CeO 2 -S catalysts from MGB are revealed to possess superior reactivity and tolerance in the model reaction of water-gas shift (WGS). The Pt 1 /CeO 2 -S catalyst exhibit 2-3 times reactivity that of their thicker counterpart, single-atom Pt 1 /CeO 2 microspheric catalyst. Moreover, the single-atom sites in Pt 1 /CeO 2 -S (1-10 %) catalysts are stable in a harsh WGS reaction condition of 10 % CO. This work thus paves a way to access the practical single-atom catalysts., (© 2022 Wiley-VCH GmbH.)

Developing electrocatalytic reactions with high-efficiency can make important contributions to carbon neutrality. However, poor long-term stability of catalysts is a bottleneck for its practical application. Herein, an "in situ periodic regeneration of catalyst (PR-C)" strategy is proposed to give long-term high efficiency of CO 2 electroreduction to generate C 2+ products over Cu catalyst by applying a positive potential pulse for a short time periodically in the halide-containing electrolyte. The high Faradaic efficiency (81.2 %) and current density (22.6 mA cm -2 ) could be maintained completely at least 36 h, while the activity and selectivity decreased continuously without using the PR-C method. Control experiments and operando characterization demonstrated that the surface structure and oxidation state of Cu could be recovered periodically by the PR-C method, which was beneficial for CO 2 activation and C-C coupling., (© 2022 Wiley-VCH GmbH.)

A coupling catalyst of highly dispersed N, P co-doped carbon frames (NPCFs) anchored with Fe single atoms (SAs) and Fe 2 P nanoparticles (NPs) is synthesized by a novel in situ doping-adsorption-phosphatization strategy for the electrocatalytic oxygen reduction reaction (ORR). The optimized Fe SAs-Fe 2 P NPs/NPCFs-2.5 catalyst shows a superior ORR activity and stability in 0.5 m H 2 SO 4 and 0.1 m KOH, respectively. Theoretical calculations reveal a synergistic effect, in that the existence of Fe 2 P weakens the adsorption of ORR intermediates on active sites and lowers the reaction free energy. The doped P atoms with a strong electron-donating ability elevate the energy level of Fe-3d orbitals and facilitate the adsorption of O 2 . The active Fe atoms exist in a low oxidation state and are less positively charged, and they serve as an electron reservoir capable of donating and releasing electrons, thus improving the ORR activity. Operando and in situ characterization results indicate that the atomically dispersed FeN 4 /FeP coupled active centers in the Fe SAs-Fe 2 P NPs/NPCFs-2.5 catalyst are characteristic of the different catalytic mechanisms in acidic and alkaline media. This work proposes a novel idea for constructing coupling catalysts with atomic-level precision and provides a strong reference for the development of high-efficiency ORR electrocatalysts for practical application., (© 2022 Wiley-VCH GmbH.)

A encapsulation-adsorption-pyrolysis strategy for the construction of atomically dispersed Co-Te diatomic sites (DASs) that are anchored in N-doped carbon is reported as an efficient bifunctional catalyst for electrocatalytic hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). The as-constructed catalyst shows the stable CoN 3 C 1 -TeN 1 C 3 coordination structure before and after HER and ORR. The *OOH/*H intermediate species are captured by in situ Raman and in situ attenuated total reflectance-surface enhanced infrared absorption spectroscopy, indicating that the reactant O 2 /H 2 O molecule has a strong interaction with the Co site, revealing that Co δ+ is an effective active site. Theoretical calculations show that the Co δ+ has adsorption-activation function and the neighboring Te δ+ acts as an electron donor adjusting the electronic structure of Co δ+ , promoting the dissociation of H 2 O molecules and the adsorption of H and oxygen-containing intermediates in HER and ORR. In the meanwhile, the nearest C atom around Co also profoundly affects the adsorption of H atoms. This results in the weakening of the OH adsorption and enhancement of H adsorption, as well as the more stable water molecule dissociation transition state, thus significantly boosting ORR and HER performance., (© 2022 Wiley-VCH GmbH.)

Electroreduction of CO 2 into valuable fuels and feedstocks offers a promising way for CO 2 utilization. However, the commercialization is limited by the low productivity. Here, we report a strategy to enhance the productivity of CO 2 electroreduction by improving diffusion of CO 2 to the surface of catalysts using porous organic cages (POCs) as an additive. It was noted that the Faradaic efficiency (FE) of C2+ products could reach 76.1 % with a current density of 1.7 A cm -2 when Cu-nanorod(nr)/CC3 (one of the POCs) was used, which were much higher than that using Cu-nr. Detailed studies demonstrated that the hydrophobic pores of CC3 can adsorb a large amount of CO 2 for the reaction, and the diffusion of CO 2 in the CC3 to the nanocatalyst surface is easier than that in the liquid electrolyte. Thus, more CO 2 molecules make contact with the nanocatalysts in the presence of CC3, enhancing CO 2 reduction and inhibiting generation of H 2 ., (© 2022 Wiley-VCH GmbH.)

High-performance, fully atomically dispersed single-atom catalysts (SACs) are promising candidates for next-generation industrial catalysts. However, it remains a great challenge to avoid the aggregation of isolated atoms into nanoparticles during the preparation and application of SACs. Here, the evolution of Pd species is investigated on different crystal facets of CeO 2 , and vastly different behaviors on the single-atomic dispersion of surface Pd atoms are surprisingly discovered. In situ X-ray photoelectron spectroscopy (XPS), in situ near-ambient-pressure-XPS (NAP-XPS), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and X-ray absorption spectroscopy (XAS) reveal that, in a reducing atmosphere, more oxygen vacancies are generated on the (100) facet of CeO 2 , and Pd atoms can be trapped and thus feature atomic dispersion; by contrast, on the CeO 2 (111) facet, Pd atoms will readily aggregate into clusters (Pd n ). Furthermore, Pd 1 /CeO 2 (100) gives a high selectivity of 90.3% for the catalytic N-alkylation reaction, which is 2.8 times higher than that for Pd n /CeO 2 (111). This direct evidence demonstrates the crucial role of crystal-facet effects in the preparation of metal-atom-on-metal-oxide SACs. This work thus opens an avenue for the rational design and targeted synthesis of ultrastable and sinter-resistant SACs., (© 2022 Wiley-VCH GmbH.)

Recognizing and controlling the structure-activity relationships of single-atom catalysts (SACs) is vital for manipulating their catalytic properties for various practical applications. Herein, Fe SACs supported on nitrogen-doped carbon (SA-Fe/CN) are reported, which show high catalytic reactivity (97% degradation of bisphenol A in only 5 min), high stability (80% of reactivity maintained after five runs), and wide pH suitability (working pH range 3-11) toward Fenton-like reactions. The roles of different N species in these reactions are further explored, both experimentally and theoretically. It is discovered that graphitic N is an adsorptive site for the target molecule, pyrrolic N coordinates with Fe(III) and plays a dominant role in the reaction, and pyridinic N, coordinated with Fe(II), is only a minor contributor to the reactivity of SA-Fe/CN. Density functional theory (DFT) calculations reveal that a lower d-band center location of pyrrolic-type Fe sites leads to the easy generation of Fe-oxo intermediates, and thus, excellent catalytic properties., (© 2022 Wiley-VCH GmbH.)

Electrocatalytic reduction of CO 2 (CO 2 RR) to value-added chemicals is of great significance for CO 2 utilization, however the CO 2 RR process involving multi-electron and proton transfer is greatly limited by poor selectivity and low yield. Herein, We have developed an atomically dispersed monovalent zinc catalyst anchored on nitrogenated carbon nanosheets (Zn/NC NSs). Benefiting from the unique coordination environment and atomic dispersion, the Zn/NC NSs exhibit a superior CO 2 RR performance, featuring a high current density up to 50 mA cm -2 with an outstanding CO Faradaic efficiency of ≈95 %. The center Zn I atom coordinated with three N atoms and one N atom that bridges over two adjacent graphitic edges (Zn-N 3+1 ) is identified as the catalytically active site. Experimental results reveal that the twisted Zn-N 3+1 structure accelerates CO 2 activation and protonation in the rate-determining step of *CO 2 to *COOH, while theoretical calculations elucidate that atomically dispersed Zn-N 3+1 moieties decrease the potential barriers for intermediate COOH* formation, promoting the proton-coupled CO 2 RR kinetics and boosting the overall catalytic performance., (© 2021 Wiley-VCH GmbH.)

Using renewable electricity to drive CO 2 electroreduction is an attractive way to achieve carbon-neutral energy cycle and produce value-added chemicals and fuels. As an important platform molecule and clean fuel, methanol requires 6-electron transfer in the process of CO 2 reduction. Currently, CO 2 electroreduction to methanol suffers from poor efficiency and low selectivity. Herein, we report the first work to design atomically dispersed Sn site anchored on defective CuO catalysts for CO 2 electroreduction to methanol. It exhibits high methanol Faradaic efficiency (FE) of 88.6 % with a current density of 67.0 mA cm -2 and remarkable stability in a H-cell, which is the highest FE(methanol) with such high current density compared with the results reported to date. The atomic Sn site, adjacent oxygen vacancy and CuO support cooperate very well, leading to higher double-layer capacitance, larger CO 2 adsorption capacity and lower interfacial charge transfer resistance. Operando experiments and density functional theory calculations demonstrate that the catalyst is beneficial for CO 2 activation via decreasing the energy barrier of *COOH dissociation to form *CO. The obtained key intermediate *CO is then bound to the Cu species for further reduction, leading to high selectivity toward methanol., (© 2021 Wiley-VCH GmbH.)

Guided by first-principles calculations, it was found that Cd single-atom catalysts (SACs) have excellent performance in activating CO 2 , and the introduction of axial coordination structure to Cd SACs cannot only further decrease the free energy barrier of CO 2 reduction, but also suppress the hydrogen evolution reaction (HER). Based on the above discovery, we designed and synthesized a novel Cd SAC that comprises an optimized CdN 4 S 1 moiety incorporated in a carbon matrix. It was shown that the catalyst exhibited outstanding performance in CO 2 electroreduction to CO. The faradaic efficiency (FE) of CO could reach up to 99.7 % with a current density of 182.2 mA cm -2 in a H-type electrolysis cell, and the turnover frequency (TOF) value could achieve 73000 h -1 , which was much higher than that reported to date. This work shows a successful example of how to design highly efficient catalysts guided by theoretical calculations., (© 2021 Wiley-VCH GmbH.)

To relieve the green gas emission and involve the carbon neutral cycle, electrochemical reduction of CO 2 attracts more and more attention. Herein, a biatomic site catalyst of Cu-Fe coordinated with the nitrogen, which is doped in the carbon matrix (denoted as Cu-Fe-N 6 -C), is designed. The as-obtained Cu-Fe-N 6 -C exhibits higher performance than that of Cu-N-C and Fe-N-C, owing to bimetallic sites, proving synergistic functions based on different molecules and their interfaces. Cu-Fe-N 6 -C shows high selectivity toward CO, with high Faradaic efficiency (98% at -0.7 V), and maintaining 98% of its initial selectivity after 10 h electrolysis. The experimental results and theoretical calculations reveal that the synergistic catalysis of different metallic sites enlarges the adsorption enthalpy of CO 2 , reducing the activation energy result in generating high selectivity, activity, stability, and low impedance., (© 2020 Wiley-VCH GmbH.)

Developing efficient photocatalysts for synchronously producing H 2 and high value-added chemicals holds great promise to enhance solar energy conversion. Herein, a facile strategy of simultaneously engineering Pd cocatalyst and oxygen vacancies (V O s) on TiO 2 to promote H 2 production coupled with selective oxidation of benzylamine is demonstrated. The optimized Pd SA+C /TiO 2 -V O photocatalyst containing Pd single atoms (SAs), clusters (C), and V O s exhibits much superior performance to those of TiO 2 -V O and Pd SA /TiO 2 -V O counterparts. The production rates of H 2 and N-benzylidenebenzylamine over Pd SA+C /TiO 2 -V O are 52.7 and 1.5 times those over TiO 2 -V O , respectively. Both experimental and theoretical studies have elucidated the synergistic effect of Pd SAs, clusters, and V O s on TiO 2 in boosting the photocatalytic reaction. The presence of Pd SAs facilitates the generation and stabilization of abundant V O s by the formation of PdOTi 3+ atomic interface, while Pd clusters promote the photogenerated charge separation and afford the optimum active sites for H 2 evolution. Surface V O s of TiO 2 guarantee the efficient adsorption and dissociation/activation of reactant molecules. This study reveals the effect of active-site engineering on the photocatalysis and is expected to shed substantial light on future structure design and modulation of semiconductor photocatalysts., (© 2020 Wiley-VCH GmbH.)

Interface engineering is promising but still challenging for developing highly efficient and stable non-noble-metal-based electrocatalysts for water splitting. Herein, partially phosphidated core@shell Co@Co-P nanoparticles encapsulated in bamboo-like N, P co-doped carbon nanotubes (denoted as Part-Ph Co@Co-P@NPCNTs) are prepared through a pyrolysis-oxidation-phosphidation strategy. In this structure, each Co nanoparticle is covered with a thin Co-P layer to form a special core@shell heterojunction interface, and the core@shell structure is further encapsulated by N, P co-doped CNTs that not only protect the Co from corrosion but also guarantee an effective and fast electron transfer on cobalt phosphide. As a bifunctional catalyst for both the hydrogen evolution reaction and oxygen evolution reaction, it exhibits an excellent activity for overall water splitting, and enables long-term operation without significant degradation. Density functional theory calculations demonstrate that the interface of the Co/Co 2 P heterojunction could lower the values of ΔG H * (hydrogen adsorption) and ΔG B (water dissociation), which are negatively correlated to the j 10 , because of the electronic structures of up-shifted d-band center. This study not only presents an efficient and stable electrocatalyst for overall water splitting but also provides a special route for the interface engineering of heterostructures., (© 2020 Wiley-VCH GmbH.)

A dual-site catalyst allows for a synergetic reaction in the close proximity to enhance catalysis. It is highly desirable to create dual-site interfaces in single-atom system to maximize the effect. Herein, we report a cation-deficient electrostatic anchorage route to fabricate an atomically dispersed platinum-titania catalyst (Pt 1 O1 /Ti 1-x O 2 ), which shows greatly enhanced hydrogen evolution activity, surpassing that of the commercial Pt/C catalyst in mass by a factor of 53.2. Operando techniques and density functional calculations reveal that Pt 1 O1 /Ti 1-x O 2 experiences a Pt-O dual-site catalytic pathway, where the inherent charge transfer within the dual sites encourages the jointly coupling protons and plays the key role during the Volmer-Tafel process. There is almost no decay in the activity of Pt 1 O1 /Ti 1-x O 2 over 300 000 cycles, meaning 30 times of enhancement in stability compared to the commercial Pt/C catalysts (10 000 cycles)., (© 2020 Wiley-VCH GmbH.)

Electroreduction of CO 2 to liquid fuels such as ethanol and n-propanol, powered by renewable electricity, offers a promising strategy for controlling the global carbon balance and addressing the need for the storage of intermittent renewable energy. In this work, we discovered that the composite composed of nitrogen-doped graphene quantum dots (NGQ) on CuO-derived Cu nanorods (NGQ/Cu-nr) was an outstanding electrocatalyst for the reduction of CO 2 to ethanol and n-propanol. The Faradaic efficiency (FE) of C2+ alcohols could reach 52.4 % with a total current density of 282.1 mA cm -2 . This is the highest FE for C2+ alcohols with a commercial current density to date. Control experiments and DFT studies show that the NGQ/Cu-nr could provide dual catalytic active sites and could stabilize the CH 2 CHO intermediate to enhance the FE of alcohols significantly through further carbon protonation. The NGQ and Cu-nr had excellent synergistic effects for accelerating the reduction of CO 2 to alcohols., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Single-atom catalysts have attracted much attention. Reported herein is that regulating charge transfer of lattice oxygen atoms in serial single-atom-doped titania enables tunable hydrogen evolution reaction (HER) activity. First-principles calculations disclose that the activity of lattice oxygen for the HER can be regularly promoted by substituting its nearest metal atom, and doping-induced charge transfer plays an essential role. Besides, the realm of the charge transfer of the active site can be enlarged to the second nearest atom by creating oxygen vacancies, resulting in further optimization for the HER. Various single-atom-doped titania nanosheets were fabricated to validate the proposed model. Taking advantage of the localized charge transfer to the lattice atom is demonstrated to be feasible for realizing precise regulation of the electronic structures and thus catalytic activity of the nanosheets., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

For electrocatalysts for the hydrogen evolution reaction (HER), encapsulating transition metal phosphides (TMPs) into nitrogen-doped carbon materials has been known as an effective strategy to elevate the activity and stability. Yet still, it remains unclear how the TMPs work synergistically with the N-doped support, and which N configuration (pyridinic N, pyrrolic N, or graphitic N) contributes predominantly to the synergy. Here we present a HER electrocatalyst (denoted as MoP@NCHSs) comprising MoP nanoparticles encapsulated in N-doped carbon hollow spheres, which displays excellent activity and stability for HER in alkaline media. Results of experimental investigations and theoretical calculations indicate that the synergy between MoP and the pyridinic N can most effectively promote the HER in alkaline media., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Electrochemical reduction of CO 2 into energy-dense chemical feedstock and fuels provides an attractive pathway to sustainable energy storage and artificial carbon cycle. Herein, we report the first work to use atomic Ir electrocatalyst for CO 2 reduction. By using α-Co(OH) 2 as the support, the faradaic efficiency of CO could reach 97.6 % with a turnover frequency (TOF) of 38290 h -1 in aqueous electrolyte, which is the highest TOF up to date. The electrochemical active area is 23.4-times higher than Ir nanoparticles (2 nm), which is highly conductive and favors electron transfer from CO 2 to its radical anion (CO 2 .- ). Moreover, the more efficient stabilization of CO 2 .- intermediate and easy charge transfer makes the atomic Ir electrocatalyst facilitate CO production. Hence, α-Co(OH) 2 -supported atomic Ir electrocatalysts show enhanced CO 2 activity and stability., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Developing an efficient single-atom material (SAM) synthesis and exploring the energy-related catalytic reaction are important but still challenging. A polymerization-pyrolysis-evaporation (PPE) strategy was developed to synthesize N-doped porous carbon (NPC) with anchored atomically dispersed Fe-N 4 catalytic sites. This material was derived from predesigned bimetallic Zn/Fe polyphthalocyanine. Experiments and calculations demonstrate the formed Fe-N 4 site exhibits superior trifunctional electrocatalytic performance for oxygen reduction, oxygen evolution, and hydrogen evolution reactions. In overall water splitting and rechargeable Zn-air battery devices containing the Fe-N 4 SAs/NPC catalyst, it exhibits high efficiency and extraordinary stability. This current PPE method is a general strategy for preparing M SAs/NPC (M=Co, Ni, Mn), bringing new perspectives for designing various SAMs for catalytic application., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Controllable synthesis of ultrasmall atomically ordered intermetallic nanoparticles is a challenging task, owing to the high temperature commonly required for the formation of intermetallic phases. Here, a metal-organic framework (MOF)-confined co-reduction strategy is developed for the preparation of sub-2 nm intermetallic PdZn nanoparticles, by employing the well-defined porous structures of calcinated ZIF-8 (ZIF-8C) and an in situ co-reduction therein. HAADF-STEM, HRTEM, and EDS characterizations reveal the homogeneous dispersion of these sub-2 nm intermetallic PdZn nanoparticles within the ZIF-8C frameworks. XRD, XPS, and EXAFS measurements further confirm the atomically ordered intermetallic phase nature of these sub-2 nm PdZn nanoparticles. Selective hydrogenation of acetylene evaluation results show the excellent catalytic properties of the sub-2 nm intermetallic PdZn, which result from the energetically more favorable path for acetylene hydrogenation and ethylene desorption over the ultrasmall particles than over larger-sized intermetallic PdZn as revealed by density functional theory (DFT) calculations. Moreover, this protocol is also extendable for the preparation of sub-2 nm intermetallic PtZn nanoparticles and is expected to provide a novel methodology in synthesizing ultrasmall atomically ordered intermetallic nanomaterials by rationally functionalizing MOFs., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)