Biomimetic tactile is a fundamental means for intelligent robots to perceive external environmental stimuli.For traditional tactile sensors, direct physical contact with the thermal source was required to obtain the temperature information. However, such contact operating mode had a notable shortcoming: the potential physical damage when processing noxious thermal stimuli.Therefore, it is necessary to develop the non-contact temperature perception function of e-skin for soft robotics and other interactive technologies.Recently, a research team led by Prof. JIANG Peng, Associate Prof. LU Xiaowei, and Prof. BAO Xinhe from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) developed a flexible and wearable long-wave infrared detector, which enabled touchless thermosensation function of electronic skin.This study was published in Advanced Materials on March 8.A flexible wearable photothermoelectric detector enables touchless thermosensation over a broad source temperature range from –50 to 110°C (Image by GUO Xiaohan and LU Xiaowei)Photothermoelectric (PTE) detectors, based on the combination of photothermal and thermoelectric conversions, can realize ultra-broadband photodetection without requiring cooling and external bias. They are particularly suitable for bionic applications involving infrared detection.In this study, the researchers developed a flexible and wearable infrared detector by coupling the Te/CuTe thermoelectric heterostructure and the infrared-absorbing polyimide (PI) substrate. They found that the Te/CuTe thermoelectric heterostructure could reduce the noise equivalent power by improving the power factor. Moreover, they realized efficient PTE coupling by suppressing the optical reflection loss and aligning the destructive interference position with the absorption peak of the PI substrate, which improved the performance of PTE detector.Besides, the researchers investigated the performance of PTE detector. They proved that when the temperature of the thermal source varied from –50 to 110°C, the fabricated flexible PTE detector, in the contactless mode, exhibited higher sensitivity than the commercial rigid thermopile. With this wearable infrared detector, they established a temperature pre-warning system for a soft robotic gripper that could distinguish the noxious thermal stimulus in a dynamic and contactless manner."This work provides a feasible strategy to integrate the infrared detection technique into the sensory modality of electronic skin, exhibiting great potential for smart robotics, artificial intelligence, and augmented reality," said Prof. JIANGThe above work was supported by the National Natural Science Foundation of China, the National Key R&D Program of China, the Natural Science Foundation of Liaoning Province, the CAS Interdisciplinary Innovation Team, and DICP.

Pyrogenic carbon is widely produced during the incomplete combustion of biomass and fossil fuels on land. About one-third of pyrogenic carbon is exported to the ocean by rivers, and thereinto, the refractory fraction becomes the source of oceanic black carbon that can provide a long-term sink for atmospheric CO2.The chemical signature of black carbon in the oceans differs from pyrogenic carbon in rivers. Specifically, unknown degradations that account for the losses of pyrogenic carbon or carbon-13 enrichment of pyrogenic carbon should exist as terrigenous refractory pyrogenic carbon transits coastal waters. Unveiling this enigma is helpful in verifying the role of oceanic pyrogenic carbon in buffering climate change, but it still needs to be clarified.Now, Prof. WANG Feng's group from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) and their collaborators have identified a degradation process that may be a significant contributor to the deposition of 13C-enriched pyrogenic carbon in coastal sediments. Their findings were published in the Journal of the American Chemical Society on Mar. 18.The coastal ocean surface harbors abundant wave energy. Wave energy dissipation through wave breaking is a prominent source of sprayed water microdroplets on Earth. Water microdroplets possess a high electric field at the interface of microdroplets, which is sufficient to pull electrons out of hydroxide ions.Researchers found that seawater microdroplets can couple this interfacial electron transfer pathway with that caused by contact electrification at microdroplet water-carbon interfaces to accelerate refractory pyrogenic carbon degradation. This electrochemical degradation process can lead to a large fractionation of stable carbon isotopes and account for the deposition of refractory pyrogenic carbon.Besides, the researchers proposed a hypothesis that the resuspension of such deposited refractory pyrogenic carbon could act as a source of 13C-enriched black carbon in the open ocean. They indicated that with intensifying wave energy due to anthropogenic global warming, the chemical effect of seawater microdroplets in the marine carbon cycle requires more attention.

Solar thermal fuels (STFs) can convert solar energy into chemical energy, which can be stored for a long time and released as thermal energy through specific triggers when needed.STFs are promising for solar thermal utilization since they can address the problems of solar energy's intermittent availability and weather/geographic dependency. However, the current research on STFs mainly focuses on molecular-based materials with different molecular conformations showing energy differences, which pose challenges in practical large-scale applications.Recently, a research group led by Prof. SHI Quan from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) has proposed an erythritol (ERY)-based spatiotemporal phase change material (STPCMs) that can serve as a new type of STFs, and have the potential for large-scale applications.This study was published in Angewandte Chemie International Edition on Feb. 20.The researchers demonstrated that the developed erythritol-polyacrylamide-polydopamine (ERY-PAM-PDA) composite STPCMs had the spatiotemporal utilization of thermal energy and photothermal conversion ability.Schematic diagram of the composite STPCM (Image by ZHANG Shihui)The researchers found that after introducing a photothermal conversion unit, the composite STPCM exhibited good photothermal conversion efficiency and realized the conversion and storage of solar energy into thermal energy. In addition, the composite STPCM could store thermal energy for more than a month at room temperature and then controllably release the stored latent heat via thermal induction or mechanical triggering. The cold crystallization enthalpy could reach 224.9 J/g, and the released latent heat could heat the system from room temperature (25 °C) to 91 °C.The composite STPCM reported in this work is a promising alternative to molecular-based STFs. It exhibited spatiotemporal utilization capabilities for thermal energy and photothermal conversion ability in the visible light region. Moreover, it had simple preparation methods, used cheap and readily available raw materials, and was applicable to large-scale production."This work provides a new direction for the application of STPCMs and the development of solar thermal utilization technology," said Prof. SHI.The above work was supported by the National Key Research and Development Program of China and the National Nature Science Foundation of China.

Direct conversion of CH4 and O2 to value-added chemicals is important for natural gas industries. However, challenges remain due to the difficulty of O2 activation in forming active oxygen species for CH4 activation under mild conditions.Recently, a research group led by Prof. DENG Dehui, Assoc. Prof. CUI xiaoju and YU Liang from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) realized the electrochemical conversion of CH4 by O2 to HCOOH at room temperature.This study was published in the Journal of the American Chemical Society and was selected as a supplementary cover.Schematic diagram of CH4 conversion to HCOOH by the hetero-homogeneous coupling electro-catalytic process (Image by Dehui Deng)The researchers developed a high-pressure electro-Fenton strategy to establish a hetero-homogeneous process for electro-catalytic conversion of CH4 by O2 at room temperature. They revealed that CH4 was efficiently activated by ·OH, which was produced via a heterogeneous electroreduction of O2 to H2O2 on the Ag foil cathode, followed by a homogeneous Fe2+-facilitated H2O2 decomposition.Besides, the researchers found that the elevated pressure not only improved the productivity of H2O2 from O2 electro-reduction but also boosted the reaction collision probability between CH4 and active ·OH in-situ generated from Fe2+-facilitated decomposition of H2O2.Compared with the traditional electro-catalytic CH4 conversion process with high overpotential (>0.9 V) and low Faradaic efficiency (< 60%), the high-pressure electro-Fenton process achieved an HCOOH Faradaic efficiency of 81.4% with an ultra-low cathodic overpotential of 0.38 V. The HCOOH productivity was 11.5 mmol h-1 gFe-1, which was 220 times that of ambient pressure."This work provides a new way for energy-efficient and sustainable conversion of CH4 by directly using O2 under mild conditions," said Prof. DENG.This work was supported by the National Key R&D Program of China, the National Natural Science Foundation of China, the Strategic Priority Research Program of CAS, and the Fundamental Research Funds for the Central Universities.

　　Photoionization (PI) is an efficient ionization technique, hyphenating to Ion Mobility Spectrometry (IMS), which has been widely employed in various on-site analysis fields such as clinical diagnosis, food quality control, environmental pollutant monitoring, and national security. However, ion loss caused by ion recombination under atmospheric pressure leads to decreased sensitivity and linear dynamic range of PI-IMS.
　　Recently, a research group led by Prof. LI Haiyang from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) conducted a study on the response profile of PI-IMS under different pressure conditions based on the independently developed PI-IMS.
　　The researchers quantitatively analyzed the factors causing ion loss, like ion recombination and space charge, to enhance the signal intensity and linear dynamic range of PI-IMS. Furthermore, they revealed factors influencing the PI-IMS response would also benefit the applications of other chemical ionization sources in IMS or mass spectrometry (MS). The study was published in Analytical Chemistry.
　　The variation trends of the optimal pressure (Poptimal) versus analyte concentration and the electric field (Image by XU Yiqian)
　　The researchers developed variable pressure PI-IMS to investigate the signal response of PI-IMS for toluene by varying its working pressure from 1 to 0.1 bar.
　　They found that ion recombination and space charge were the primary factors contributing to ion loss under high-pressure and low-pressure conditions. They derived a simplified theoretical equation taking ion recombination as the primary ion loss factor to link the optimal pressure with analyte concentration and electric field.
　　Compared to the ambient pressure, they found that PI-IMS at 0.4 bar provided a signal intensity increment of over 400% for 0.716 ppmv of toluene, and the linear dynamic range was also expanded over two times.
　　The above study was supported by the National Natural Sciences Foundation of China and the National Key Research and Development Program of China.

　　Direct methane conversion has advantages such as low energy consumption, less processes, and better economics. However, it is difficult to activate methane at room temperature due to the high dissociation energy of C-H bonds of methane. Additionally, the target products, such as methanol, acetic acid, and other oxygenates, are prone to over-oxidation, resulting in the generation of CO2. Therefore, the design of catalysts with high activity and selectivity is important.
　　Recently, a group led by Prof. ZHANG Tao, Prof. WANG Xiaodong, and Asso. Prof. HUANG Chuande from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. CHANG Chunran's group from Xi'an Jiaotong University, have realized the efficient direct conversion of methane through single-atom catalysis at room temperature.
　　This study was published in Angewandte Chemie International Edition.
　　Direct methane conversion to acetic acid over CO-promoted Pd1-ZSM-5 single-atom catalyst (Image by XU Weibin)
　　The researchers proposed a strategy involving CO molecule modification to regulate the electronic structure of single-atom catalyst M1-ZSM-5 (M = Rh, Ru, Fe), which enhances the efficiency of direct methane conversion. They realized catalyzing methane conversion with H2O2 as an oxidant at room temperature (25℃), the turnover frequency (TOF) of Pd1-ZSM-5 reached 207 h-1 with nearly 100% selectivity towards oxygenates.
　　Combining experimental characterization with density functional theory (DFT) calculations, the researchers discovered that the C atom in the CO molecule tends to coordinate with the Pd1 single atom, transferring electrons from CO to the active oxygen center L-Pd1-O (L = CO), resulting in the reduce of the dissociation barrier of C-H bonds of methane, from 1.27 eV to 0.48 eV.
　　Moreover, this strategy exhibited good universality as TOF of the M1-ZSM-5 (M = Rh, Ru, Fe) series catalysts could be increased by 3.2 to 11.3 times through CO molecule modification.
　　"We have developed the electronically tunable molecular sieve-supported M1-O isolated active centers, providing a new method to achieve selective methane conversion to chemicals under mild conditions," said Prof. WANG.
　　This work was supported by the National Natural Science Foundation of China (NSFC), the Youth Innovation Promotion Association of CAS, and the NSFC Center for Single-Atom Catalysis.